Most recent papers:

• Custodians of Controversy: Navigating Stewardship Challenges With Non‐Consensual Anatomized Human Skeletonized Individuals in South Africa.
  A. Alblas, V. E. Gibbon.
  American Journal of Physical Anthropology. July 02, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 3, July 2026. ", "\nABSTRACT\nSouth Africa, like many countries, holds collections of human skeletonized individuals historically acquired through anatomical dissection programs. This paper examines non‐consensual anatomized and unclaimed (NCAU) state‐directed skeletonized individuals, whose presence in collections pose significant legal, ethical, and professional challenges. Although the National Health Act (2003) outlines procedures for body donation, the inclusion of unclaimed and destitute persons obtained without consent raises ethical concerns. As curators and custodians, a perspective is provided, assessing the legal and ethical implications of retaining NCAU skeletonized individuals and highlighting inconsistencies between South African regulations and international standards that prioritize informed consent and dignity‐in‐death. The complexities surrounding the retention, use, or disposition of these decedent bodies, and parts thereof, are discussed, offering recommendations for institutional decision‐making to navigate these complexities. A structured and multidisciplinary approach is provided we advocate for transparent and ethically responsible stewardship of NCAU collections. Furthermore, the pressure placed on curators is noted, who face potential personal and professional repercussions, and emphasizes the need for institutional support, training, and resources to guide ethical management and facilitate informed decision‐making of these sensitive collections.\n"]

  July 02, 2026   doi: 10.1002/ajpa.70300   open full text
• Stable Isotope Values in Human Dentine Collagen and Fingernails Reveal Age‐Related and Socioeconomic Dietary Patterns in Brazil.
  Juliana S. Emenes, Murillo Q. R. Bastos, Rachel Tinoco, Ricardo O. Mascarenhas, Anelize Manuela Bahniuk Rumbelsperger, Emanuelle L. Ferreira de Lima, Luciano Henrique de Jesus, Roque Soares Martins, Cosmo Helder Ferreira da Silva, Gabriela B. Nardoto, Luiz A. Martinelli.
  American Journal of Physical Anthropology. June 30, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 3, July 2026. ", "\nABSTRACT\n\nObjectives\nIn this study, we analyzed δ13C and δ15N values in dentine collagen (reflecting early‐life diet) and fingernail keratin (reflecting recent diet) from 92 living adult individuals, having 75 individuals having paired dentine and fingernail samples available, across Brazilian regions with contrasting socioeconomic conditions. While the sample size was necessarily limited by the availability of paired tissues, it provides a unique dataset for assessing dietary change within the lifespan and its relationship to socioeconomic context.\n\n\nMaterials and Methods\nUsing Bayesian linear models and self‐reported dietary intake questionnaires, we investigated the influence of age, geographic region, and socioeconomic status on isotopic composition.\n\n\nResults\nWe found significant regional and socioeconomic effects: individuals from high‐Human Development Index (HDI) municipalities and those reporting greater sugar intake had elevated δ13C values, while frequent fish and seafood consumption was associated with higher δ15N. Notably, δ15N in dentine collagen declined with tooth age, suggesting a historical decrease in the δ15N of food sources, likely linked to increased reliance on synthetic fertilizers and nitrogen‐fixing crops.\n\n\nDiscussion\nBoth tissues show a consistent regional contrast: participants from the Southeast exhibit higher δ13C and lower δ15N than those from the Northeast, consistent with greater intake of C4‐derived, corn‐ and sugar‐based processed foods (“supermarket diet”’) and proportionally lower trophic‐level protein in the Southeast, versus lower δ13C in the Northeast consistent with diets centered on C3 staples (rice, beans, manioc) and more limited access to ultra‐processed foods.\n\n"]

  June 30, 2026   doi: 10.1002/ajpa.70258   open full text
• “Ethics Seems Like an Afterthought”: An Argument for Prioritizing Ethics Education in Anthropology Curricula.
  Malorie E. Albee, Emma L. Roach, Rachel E. Smith, Ryan N. Bishop.
  American Journal of Physical Anthropology. June 30, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 3, July 2026. ", "\nABSTRACT\n\nObjectives\nAccording to the American Association of Biological Anthropologists Code of Ethics, “departments offering anthropology degrees should include and require ethical training in their curriculums.” Ethics training is essential, but are Anthropology undergraduate and graduate programs incorporating ethics education as part of their core curriculum? Do Anthropology undergraduate and graduate students feel like they are receiving adequate education and training in ethics as part of their program curriculum?\n\n\nMaterials and Methods\nThis study attempts to answer these questions by analyzing undergraduate degree requirements for Anthropology majors in the U.S. and by surveying U.S.‐based Anthropology teaching faculty and undergraduate and graduate students. These surveys include questions about Anthropology curricula, program and course learning objectives, and student preparedness in facing ethical dilemmas post‐graduation. In total, 142 individuals participated in the survey (94 students, 48 faculty members).\n\n\nResults\nThe results of this survey indicate that some Anthropology undergraduate and graduate programs are incorporating ethics education as part of their core curriculum, but this is not true for all programs. Unfortunately, the most frequent response was that ethics education was not incorporated into the core curriculum, and students, especially graduate students, do not feel that they are receiving adequate ethics education.\n\n\nDiscussion\nResults of this study reveal a gap between the ideal practice proposed in professional academic organizations' codes of ethics and the reality of this application, as well as a disconnect between faculty and student perceptions of the sufficiency of the ethics education being provided. Specific recommendations for filling these gaps are provided.\n\n"]

  June 30, 2026   doi: 10.1002/ajpa.70303   open full text
• The Effect of Migration on Perceived Safety and Sleep Quality: An Analysis From Rural and Urban Indigenous Wixárika Communities in Jalisco, MexicoEl efecto de la migración en la seguridad percibida y la calidad del sueño: un análisis en comunidades indígenas Wixaritari rurales y urbanas en Jalisco, México.
  Leela McKinnon, Eric C. Shattuck, Igor Martín Ramos Herrera, René Cristobal Crocker Sagastume, Quetzabel de la Cruz, Paritemai González Torrez, Thankam Sunil, David R. Samson.
  American Journal of Physical Anthropology. June 30, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 3, July 2026. ", "\nABSTRACT\n\nObjectives\nThis study explores how perceived safety influences sleep quality among Wixárika individuals in Mexico. We compared the sleep quality of those living in a rural town in northern Jalisco with those living in the Guadalajara Metropolitan Area (GMA). We aimed to assess differences in perceived safety, model its association with sleep outcomes, and test for gendered effects.\n\n\nMethods\nSleep was measured using actigraphy and surveys. Perceived neighborhood safety (PNS) was measured with survey items. Sleep outcomes included efficiency, fragmentation, wake after sleep onset (WASO), self‐rated quality, and daytime dysfunction. Analyses used Mann–Whitney U tests, linear mixed effects models, and logistic regression.\n\n\nResults\nOur sample included 127 participants. In the rural location (n = 61), the mean age was 38.02 years (SD = 12.18, range = 18–65), with 72.13% comprised of women. In the GMA, the mean age was 29.59 years (SD = 8.43, range = 18–57), of whom 65.15% were women. PNS was significantly higher in the rural town than in the GMA. Gender moderated the association between PNS and sleep quality, with women showing improved sleep quality with greater PNS. Poorer mental health predicted lower sleep quality in rural participants and greater odds of daytime dysfunction in urban participants.\n\n\nConclusions\nIn our analyses, living in urban contexts is associated with reduced perceived safety, which interacts with gender to shape sleep. Women's sleep appears to be particularly sensitive to perceived safety, reflecting broader intersecting vulnerabilities and health inequities faced by Indigenous migrant women. Policies addressing housing and neighborhood safety, alongside culturally grounded supports, may improve sleep health in these communities.\n\n\nRESUMEN\n\nObjetivos\nEste estudio explora cómo la percepción de seguridad influye en la calidad del sueño entre individuos Wixaritari en México. Comparamos la calidad del sueño de quienes viven en un pueblo rural en el norte de Jalisco con aquellos que viven en la Zona Metropolitana de Guadalajara (ZMG). Nuestro objetivo fue evaluar diferencias en la percepción de seguridad, modelar su asociación con los resultados de sueño y probar efectos diferenciados por género.\n\n\nMétodos\nEl sueño fue medido mediante actigrafía y encuestas. La percepción de seguridad vecinal (PNS) se midió con preguntas de encuesta. Los resultados de sueño incluyeron eficiencia, fragmentación, vigilia después del inicio del sueño, calidad autoevaluada y disfunción diurna. Los análisis emplearon pruebas U de Mann–Whitney, modelos lineales de efectos mixtos y regresión logística, controlando por edad, salud física y mental autoevaluadas, y tiempo en cama.\n\n\nResultados\nNuestra muestra total incluyó 127 participantes (edad media = 33.64 años, DE = 11.19; rango = 18–65), de los cuales el 68.5% eran mujeres. En la localidad rural (n = 61), la edad media fue de 38.02 años (DE = 12.18, rango = 18–65), con un 72.13% de la muestra compuesto por mujeres. En la ZMG, la edad media fue de 29.59 años (DE = 8.43, rango = 18–57), de los cuales el 65.15% eran mujeres. La percepción de seguridad fue significativamente mayor en quienes habitan en comunidad rural que en la ZMG. El género moderó la asociación entre la seguridad percibida y las métricas de calidad del sueño en las muestras urbanas, y las mujeres mostraron una mejor calidad del sueño a medida que aumentaba la seguridad percibida. Una peor salud mental predijo un sueño más fragmentado y menos eficiente en los participantes rurales, y mayores probabilidades de disfunción diurna en los participantes urbanos.\n\n\nConclusiones\nEn nuestros análisis, vivir en contextos urbanos se asocia con menor percepción de seguridad, lo cual interactúa con el género para moldear los resultados del sueño. El sueño de las mujeres parece ser particularmente sensible a la percepción de seguridad, lo que refleja vulnerabilidades e inequidades en salud más amplias e interseccionales que enfrentan las mujeres indígenas migrantes. La salud del sueño en estas comunidades puede mejorar mediante políticas que atiendan la vivienda y la seguridad vecinal, junto con apoyos culturalmente pertinentes.\n\n"]

  June 30, 2026   doi: 10.1002/ajpa.70307   open full text
• Principal Components Analysis Fails to Recover Phylogenetic Structure in Hominins.
  Levi Y. Raskin, Maja Šešelj, Bárbara D. Bitarello, Sofia Stroustrup, Jacky K. Li, John Huelsenbeck.
  American Journal of Physical Anthropology. June 30, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 3, July 2026. ", "\nABSTRACT\n\nObjectives\nPaleoanthropologists often utilize geometric morphometrics and principal components analysis (PCA) to interpret shape variation within the hominin fossil record. It is common practice to interpret proximity in principal components (PC) space among taxa as indicative of not just morphological but also phylogenetic affinity. This interpretation, however, has not been directly evaluated for hominins.\n\n\nMaterials and Methods\nFirst, we inferred the posterior distribution of hominin phylogenetic trees and subsampled trees from this distribution. On these phylogenies, we simulated 2D and 3D geometric morphometric datasets and traditional morphological datasets, containing traits analogous to measurements of size or length, with varying numbers of landmarks or traits and evolutionary rates. On each dataset, we conducted a PCA and used neighbor‐joining to infer evolutionary relationships from the PC scores of each taxon. We measured the difference between the PCA tree and sampled tree with subtree pruning and regrafting distance and Robinson‐Foulds distance.\n\n\nResults\nPCA trees inferred from traditional morphometric data were identical to the sampled tree in 0.11% of datasets when we only considered PC axes 1 and 2, and in 2.9% of datasets when we considered all axes. No PCA tree inferred from any of the 2,400,000 shape datasets was identical to the sampled tree, regardless of the number of axes.\n\n\nDiscussion\nPhylogenetic interpretations of the hominin fossil record based on proximity in PC space are inherently flawed and likely to be erroneous. Arguments in the hominin systematics literature based on PCA, whether implied or explicit, should therefore be reevaluated using phylogenetically informed alternatives.\n\n"]

  June 30, 2026   doi: 10.1002/ajpa.70306   open full text
• Menopause Averted a Midlife Energetic Crisis With Help From Older Dependent Children and Parents: A Simulation Study.
  Edward H. Hagen.
  American Journal of Physical Anthropology. June 28, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 3, July 2026. ", "\nABSTRACT\n\nObjectives\nThe grandmother hypothesis proposes that ancestral women ceased reproduction midlife to instead provision their grandchildren. An alternative “two‐sex” account proposes that the high energetic burden of caring for slow‐developing offspring was met with biparental investment. Menopause evolved because the physiological costs of reproduction increased with age, yet productivity also increased with age, and the benefits of resource transfers by parents and grandparents of both sexes to adult children and their offspring eventually outweighed the diminishing benefits of continued reproduction. The “father absent” hypothesis proposes that the higher mortality rate of husbands would often have left wives without the resources to raise young children, selecting for early reproductive cessation. Juvenile production plays little role in the three hypotheses, yet subsequent studies have found it to be surprisingly high.\n\n\nMaterials and Methods\nSimulations were conducted of hunter‐gatherer energy consumption and production across the lifespan, taking account of age‐ and sex‐specific survivorship, interbirth intervals, and varying rates of foraging skill acquisition typical of contemporary foragers.\n\n\nResults\nThere is a pronounced midlife energy deficit that could be averted with the increasing production of maturing juveniles; midlife cessation of reproduction, which limited the number of mouths to feed; and energy transfers from older parents, and sometimes younger couples (e.g., brideservice).\n\n\nDiscussion\nMenopause emerges as an integral and necessary component of the unique human pattern of relatively short interbirth intervals, a long period of juvenile dependency, and extensive food sharing, supporting and extending the “two sex” and grandmother hypotheses.\n\n"]

  June 28, 2026   doi: 10.1002/ajpa.70295   open full text
• Correspondence Among Locomotor Profiles, Daily Stride Cycles, and Femoral Bone Robusticity in Taï Forest Cercopithecids.
  David J. Daegling, Jordan N. Traff, Tessa H. C. Wilde, E. Anderson Bitty, W. Scott McGraw.
  American Journal of Physical Anthropology. June 21, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nThis study explores linkages between daily locomotor cycles to structural and material biomechanical variables in four sympatric West African cercopithecid species. While functional studies of primate postcrania typically rely on locomotor and activity profiles to create a context for biomechanical interpretation, two variables not typically included in such studies are stride counts and rest intervals. The former provide information on cumulative daily loads, while the latter have been shown to have positive osteogenic effects.\n\n\nMaterials and Methods\nDaily stride cycle counts in four adult females representing four sympatric cercopithecid species were collected over 30‐day periods. Individuals of the western red colobus (Piliocolobus badius), black and white (king or pied) colobus (Colobus polykomos), Diana monkey (Cercopithecus diana), and sooty mangabey (Cercocebus atys) were followed in the Taï Forest, Côte d'Ivoire. We also recruited existing data on activity patterns to provide a qualitative assessment of the amount of daily rest among these species. We utilized existing data on femoral mechanical properties from individuals within these populations to discern whether the number of daily locomotor cycles corresponded with indices of bone robusticity.\n\n\nResults\nDifferences in daily stride counts distinguish the four individuals, with higher stride counts characterizing the representatives of the two cercopithecine species. We do not observe a correspondence between stride counts and measures of long bone robusticity. Cumulative daily loads do not correspond to stronger or denser bones.\n\n\nDiscussion\nThe inclusion of information on rest duration and spacing may clarify functional linkages between locomotor behavior and skeletal mechanical properties.\n\n"]

  June 21, 2026   doi: 10.1002/ajpa.70296   open full text
• Cercopithecid Monkeys From the Pleistocene Markaytoli Site at Ledi‐Geraru, Afar Region, Ethiopia.
  Irene E. Smail, Julia L. Arenson, Christopher C. Gilbert, Eric J. Sargis, Amy L. Rector, Kaye E. Reed.
  American Journal of Physical Anthropology. June 15, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nCercopithecid monkeys are ubiquitous across much of sub‐Saharan Africa today, where they contribute much to the ecological and taxonomic diversity seen in modern African primate communities. Plio‐Pleistocene assemblages from eastern Africa also preserve a rich cercopithecid fossil record, albeit one dominated by papionins and by larger‐bodied colobine taxa; smaller‐bodied colobines and guenons remain relatively rare in this period. Here we report on a fossil monkey assemblage from the Markaytoli collection area within the Ledi‐Geraru Research Project permit region.\n\n\nMaterials and Methods\nFrom 2012 to 2020, approximately 750 fossil specimens were recovered from the Markaytoli, including nearly 100 assigned to the family Cercopithecidae. These are compared to modern African cercopithecids and to fossil evidence from other Pleistocene sites in eastern Africa, especially the Afar Region.\n\n\nResults\nThe cercopithecid fauna from Markaytoli is dominated by specimens we attribute here to Colobus sp. and Chlorocebus sp., with limited evidence for a large papionin. The Colobus and Chlorocebus material is comparable to that from other Middle Pleistocene sites (e.g., Asbole, Andalee) but shows some potential differences compared with Late Pleistocene samples (e.g., Halibee) and modern representatives.\n\n\nDiscussion\nThese fossils add to a growing record of fossil colobines and guenons from the Pleistocene of the Afar Region. Similarities with other Middle Pleistocene monkey samples support initial biochronological analyses from non‐primate taxa for the site. More work is needed to clarify the meaning of potential morphological differences between a growing ~Middle Pleistocene sample and Late Pleistocene or modern Chlorocebus and Colobus in the Awash Valley Region.\n\n"]

  June 15, 2026   doi: 10.1002/ajpa.70288   open full text
• New Insights Into Cranial Base Ontogeny in Modern Humans Through Morphometric Analysis.
  Amaëlle Sourbé, Mathilde Savignat, Frédéric Santos, Thomas Colard.
  American Journal of Physical Anthropology. June 11, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nThe cranial base is located at the interface between the face, the brain, and the vertebral column. Understanding its growth is essential for elucidating key aspects of craniofacial development, neurodevelopment, and locomotor function. This study aims to examine the developmental trajectories of the three cranial fossae, anterior, middle, and posterior, in terms of both size and shape.\n\n\nMaterials and Methods\n203 CT scans of individuals aged from birth to 15 years were segmented and analyzed. Traditional morphometric analyses based on linear measurements were first conducted to assess changes in length and width during growth. Geometric morphometric methods were applied to investigate shape variation, using a template of 32 anatomical landmarks and two curves of semi‐landmarks.\n\n\nResults\nGrowth of the cranial base followed a rapid phase from 0 to 2 years and a slower growth until adolescence. Transverse dimensions generally reach adult proportions earlier than anteroposterior lengths. The posterior fossae exhibit pronounced anteroposterior and transverse expansion. Shape analyses reveal coordinated changes of fossae boundaries, including reorientation of the petrous temporal bones and increased curvature of the sphenoid wings. Strong allometric relationships and morphological integration are observed during the initial rapid growth phase. Sexual dimorphism has a statistically significant but moderate effect on cranial base fossae shape during ontogeny.\n\n\nDiscussion\nThe cranial base exhibits biphasic growth, early‐integrated shape changes, and later modularization, reflecting coordinated cranial and brain development. These patterns provide a reference for comparative studies in primates and highlight the importance of cranial base development for neurocranial and facial morphogenesis.\n\n"]

  June 11, 2026   doi: 10.1002/ajpa.70286   open full text
• All About That Base: Dietary Plasticity, Basicranial Flexion and Sphenoid Form.
  Elizabeth Jewlal, Susan E. Lad, Matthew J. Ravosa.
  American Journal of Physical Anthropology. June 08, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nThe mammalian sphenoid is a morphologically and embryologically complex bone bridging the cranial vault and face. Sphenoid phenotypic diversity has been attributed to the coaction of natural selection and developmental variation in adjacent cranial organs and bones. These associations underscore enduring interest in the evolutionary, ontogenetic, and clinical importance of the sphenoid. We address key gaps regarding several structural and adaptive factors that differentially characterize postnatal ontogeny when brain growth is negligible and has a correspondingly diminished impact.\n\n\nMaterials and Methods\nWe employ microCT data from a well‐known rabbit model of long‐term dietary plasticity to address variation in two putative influences on the sphenoid: face length on basicranial flexion and osteogenesis in the pterygoid plates and sphenoid joints. Examining the roles of cyclical loading and feeding modality on basicranial flexion and sphenoid robusticity contributes uniquely to understanding the multifactorial nature of skull growth and form in mammals.\n\n\nResults\nPostnatal increases in facial length do not drive corresponding decreases in basicranial flexion, suggesting that flexion is primarily established during prenatal development due to changes in encephalization. Sphenoid joints and pterygoid plates exhibit diet‐related plasticity, highlighting adaptive changes due to elevated cyclical loading and feeding modality that vary depending on the bony site as well as the hierarchical level of a given region of interest.\n\n\nDiscussion\nOur findings highlight the importance of cyclical loading and feeding modality in shaping postnatal craniofacial development, necessitating the consideration of these factors in studies of structure and function across extant and extinct mammalian taxa.\n\n"]

  June 08, 2026   doi: 10.1002/ajpa.70282   open full text
• A Fully Bayesian Approach to Adult Skeletal Age Estimation: Multivariate Latent Trait Modeling With Markov Chain Monte Carlo Sampling.
  Nils Müller‐Scheeßel, Katharina Fuchs, Christoph Rinne.
  American Journal of Physical Anthropology. June 07, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nOrdered probit regression is used as a latent trait model, with age at death estimated from a Gompertz distribution. Combined with Bayesian Markov Chain Monte Carlo sampling, this approach eliminates the need for reference priors for transition ages or population parameters.\n\nABSTRACT\n\nObjectives\nThis paper investigates the potential of Bayesian transition analysis for improving age‐at‐death estimation in osteological datasets, utilizing the software NIMBLE and JAGS (Just Another Gibbs Sampler). We aim to explore the applicability of this method to different skeletal datasets including different age markers.\n\n\nMaterials and Methods\nTransition analysis models estimations of skeletal age markers based on age‐at‐transition and population priors. This study extends the methodology by integrating multiple latent traits into a Bayesian framework. Our probit regression model estimates age‐at‐death and Gompertz distribution parameters directly and without relying on predefined reference populations for age‐at‐transition or population priors. The analysis includes data from three distinct sources, which contain diverse sets of age markers with known age‐at‐death.\n\n\nResults\nThe model demonstrates good performance across the datasets and successfully estimates mortality patterns. Sample size does matter, but even smaller samples can still yield useful results. The same is true for the number of traits. A simple multiple‐probit regression will underestimate age ranges, but calibration improves upon this. Even with missing data, our model produces robust estimates.\n\n\nDiscussion\nThe results highlight the model's effectiveness in improving age‐at‐death estimations and mortality patterns across diverse populations. This Bayesian transition analysis offers a reliable and flexible method for age estimation in bioarchaeological applications on datasets with varying qualities of morphological age indicators. Even compatibility between populations is not mandatory. It is only necessary that there be an observer‐consistent age marker evaluation per skeletal assemblage and that the trait(s) in question change monotonically with biological age.\n\n"]

  June 07, 2026   doi: 10.1002/ajpa.70289   open full text
• Ecology of Malaria Mortality: A Spatiotemporal Mapping Approach.
  Amanda Cooke, Megan B. Brickley.
  American Journal of Physical Anthropology. June 04, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nThis study examines the spatiotemporal ecology of probable malaria mortality in 19th‐century southern Ontario to evaluate how settlement expansion, landscape transformation, and infrastructure development structured transmission risk in a temperate, settler‐colonial context.\n\n\nMaterials and Methods\nProbable malaria‐attributed deaths recorded in Ontario death certificates (1869–1900; n = 2683) were geocoded and analyzed using Geographic Information Systems (GIS). Mortality locations were examined in relation to historical settlements, railways, and wetlands derived from 19th‐century spatial datasets. Spatial clustering was assessed using Average Nearest Neighbor analysis and kernel density estimation. Temporal changes in proximity to landscape features were tested using nonparametric statistics, while malaria mortality density was modeled using negative binomial regression and generalized additive models.\n\n\nResults\nMalaria mortality was significantly clustered across all decades but became progressively less spatially concentrated through time. Mortality locations shifted farther from mapped wetlands as drainage intensified, while proximity to settlements consistently decreased. Regression models identified settlement proximity as the strongest and only significant predictor of malaria mortality density, whereas distances to wetlands were not independently associated once settlement effects were accounted for.\n\n\nDiscussion\nThese results indicate a reorganization of malaria risk from environmentally constrained ecologies toward anthropogenic landscapes shaped by settlement, agriculture, and infrastructure. Malaria transmission in southern Ontario was embedded within everyday settlement practices rather than static environmental features, demonstrating how colonial landscape transformation structured disease risk in a temperate region. This study highlights the value of spatiotemporal GIS approaches for interpreting past disease ecologies within biological anthropology and paleopathology.\n\n"]

  June 04, 2026   doi: 10.1002/ajpa.70272   open full text
• Microstructural Evidence for Early Childhood Stress in a Community in Transition at Hisban, Jordan.
  Kristina Cockerille, Akacia Propst, Bonnie Kahlon, Daniel Temple, Megan Perry.
  American Journal of Physical Anthropology. June 03, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nIdentification of stress across infancy and childhood can reflect maternal and environmental influences on early life health. In the 19th century community of Hisban, many infants died before 2 years of age with evidence of metabolic disease, including rickets, that likely ties with maternal health. Here the patterns and timing of accentuated lines (AL) in enamel and interglobular dentin (IGD) in dentin in older children, adolescents, and adults from this community are assessed within the mother‐infant nexus framework to highlight factors contributing to surviving past infancy. We likewise critically examine IGD as a reflection of early life stress, including nutritional or non‐nutritional rickets.\n\n\nMaterials and Methods\nHistological analysis of 29 first and second permanent molars representing 23 non‐infant individuals identified the presence and age of IGD formation. Extreme care was taken to identify developmental IGD and remove these observations from analysis. A subsample of six teeth was also observed for AL formation. Ages of IGD and AL formation followed established methods.\n\n\nResults\nMost non‐adults (65.2%) had at least one episode of IGD formation, and while all six individuals analyzed for AS and IGD had AL, only one had no evidence of IGD. AL developed at ages much earlier than IGD, although both indicate that the individuals who survived infancy also faced multiple stressors during early life.\n\n\nDiscussion\nThe ages of IGD and AL development would indicate that these individuals grappled with multiple causes of physiological stress, but not concurrently. Many biocultural factors could have caused these stressors, primarily mother‐infant interactions.\n\n"]

  June 03, 2026   doi: 10.1002/ajpa.70292   open full text
• Childhood Physical Activity and Developmental Niche in Contemporary Pastoralist Maasai Community in Southern Kenya.
  Xiaojie Tian, Tetsuhiro Kidokoro, Francis Mundia Mwangi, Elijah Gitonga Rintaugu.
  American Journal of Physical Anthropology. June 01, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nAlthough increasing attention has been directed toward childhood physical activity (PA) in small‐scale societies of the Global South, evidence across the full developmental span remains limited and is often interpreted without sufficient attention to local parental environments, norms, or children's social roles. This study examines PA among pastoralist Maasai children in southern Kenya from an ecocultural perspective.\n\n\nMaterials and Methods\nPA and sedentary behavior were assessed in 180 children aged 2–18 years using waist‐worn three‐axis accelerometers, which enabled comparisons across age, sex, day type, and school attendance. Quantitative data were complemented by long‐term ethnographic fieldwork on children's daily routines and parental practices, providing context for the developmental niche.\n\n\nResults\nMaasai children demonstrated consistently high levels of moderate‐to‐vigorous physical activity (MVPA) across all ages. Mean MVPA rose from 89 min/day (ages 2–5) to 130–143 min/day (ages 6–12), accompanied by 17,000–21,000 steps/day. Boys were generally more active than girls. Variation by school attendance reflected local norms emphasizing childhood autonomy, staged social participation, and engagement with the landscape through daily tasks and play.\n\n\nDiscussion\nThese findings provide the first comprehensive assessment of childhood PA across the full developmental span of a pastoralist Maasai community. Children's high activity levels are sustained within culturally meaningful developmental niches that foster autonomy and embodied engagement with the land, alongside contemporary transitions such as schooling. The study underscores the importance of etic–emic integration for understanding childhood PA in small‐scale societies.\n\n"]

  June 01, 2026   doi: 10.1002/ajpa.70283   open full text
• Sensorimotor Complexity and Cognition as Predictors of Primate Brain Size.
  Zitan Song, Sandra A. Heldstab, Richard F. Kay, E. Christopher Kirk, Carel P. van Schaik.
  American Journal of Physical Anthropology. May 30, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 2, June 2026. ", "\nABSTRACT\n\nObjectives\nAs animal brain size increases, cognitive performance generally increases. However, other key brain functions, such as the regulation of somatic processes, processing of sensory input, and planning and initiation of motor actions, are also closely tied to brain size. Thus, the observed correlations between cognitive performance and brain size may be spurious, a suggestion boosted by recent work showing fishes perform as well as primates on various cognitive tests.\n\n\nMaterials and Methods\nHere, we applied multi‐response Bayesian phylogenetic mixed models, in which the four main functions of brains were dependent variables predicted by brain size as the independent variable, as well as a phylogenetic path analysis.\n\n\nResults\nAmong varying sets of primate species, brain size strongly predicted somatic functions (as indexed by body size), with similar, somewhat weaker effect sizes for the other three functional traits. The path analysis suggested that body size also independently affected brain size, which in turn predicted the three non‐somatic functions with nearly equal strength.\n\n\nDiscussion\nThis result suggests that the correlation between body and brain size is the sum of two distinct processes: correlated evolution between body and brain size and a brain size effect on somatic functions, although estimating the strength of the two components is currently impossible. We reject the challenge posed by cognition data on fishes, but find that primate cognition tightly coevolved with sensory and motor functions.\n\n"]

  May 30, 2026   doi: 10.1002/ajpa.70281   open full text
• Reconstructing Lifeways and Social Differentiation in the Pre‐Pottery Neolithic B Population of Nahal Yarmuth 38, Central Israel.
  Yulia Makoviychuk, Viviane Slon, Dana Ackerfeld, Prajjval Pratap Singh, Pnina Cohen, Avi Gopher, Hila May.
  American Journal of Physical Anthropology. May 25, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nThis study presents a bioarcheological analysis of skeletal remains from Nahal Yarmuth 38 (NY38), a distinctive Middle Pre‐Pottery Neolithic B site in central Israel. The research aimed to reveal the demographic composition, origins, and lifeways of the NY38 people, to contextualize the site's unique archeological features within broader regional frameworks.\n\n\nMaterials and Methods\nOsteobiographical analyses reconstructed daily life aspects, including physical activity, dietary habits, and physiological stress. Burial practices were classified by type, body position, and architectural contexts and examined alongside demographic and biological data. Sex and age were estimated where preservation permitted, and ancient DNA analyses explored biological origins. Lifestyle and stress were evaluated through femoral midshaft cross‐sectional geometry analysis, musculoskeletal stress markers, dental disease and wear, and physiological stress indicators (enamel hypoplasia, stature, and relative medullary cavity area). Pathological bone lesions were also documented.\n\n\nResults\nThe NY38 population was local and sedentary, yet engaged in physically demanding, possibly hunting‐related activities. Evidence suggests an age‐structured social organization and a sex‐based division of labor. Physiological stress indicators revealed a challenging environment throughout life, though the survival of individuals despite the stress events suggests biological resilience. Various nonspecific pathological lesions were also identified.\n\n\nDiscussion\nThe integration of archeological and osteological data, such as a small site area, high burial density, absence of residential activity, relatively low infant mortality despite persistent physiological burdens, and distinctive mortuary treatments for selected individuals, supports the interpretation that NY38 functioned as a designated burial ground rather than a habitation site.\n\n"]

  May 25, 2026   doi: 10.1002/ajpa.70280   open full text
• Early to Middle Holocene Hunter‐Fisher‐Gatherers From the Green Sahara (Gobero, Niger): Dental Evidence for Regional African Affinities.
  Christopher M. Stojanowski, Joel D. Irish, Paul C. Sereno.
  American Journal of Physical Anthropology. May 25, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nWe assess patterns of dental morphological variation at the site of Gobero, located in central Niger, to test competing models of population history in northern Africa during the Holocene “Green Sahara” period. We test three competing models: East African Dispersal Model, Maghreb Dispersal Model, and Multisource Dispersal Model.\n\n\nMaterials and Methods\nData were collected on dental morphological variables using the Arizona State University Dental Anthropology system for two successive occupation phases at the Gobero site (Early and Middle Holocene). Using Mean Measure of Divergence statistics, these data were compared to Late Pleistocene, Early Holocene, and Middle Holocene sites from 22 premodern dental samples from the Maghreb, Nile Valley, and eastern, central, and southern Africa. Results were visualized using MDS ordination. Analyses were run using a 35‐trait and a 26‐trait data matrix.\n\n\nResults\nThe resulting inter‐sample affinities suggest that time‐successive Gobero populations are dentally indistinguishable, suggesting continuity of populations through time at the site despite significant climate deterioration. Both the Early and Middle Holocene samples at Gobero share dental affinities with Nile Valley populations, in particular the multicomponent Sudanese site of al‐Khiday. However, both samples also show intermediate affinities with northern and sub‐Saharan African populations.\n\n\nDiscussion\nThese results suggest that for most of the Holocene, an admixed population was present in the central Sahara with a primarily East African/Nile Valley origin. Nonetheless, as the climate deteriorated we cannot discount population interactions with northern African and sub‐Saharan populations.\n\n"]

  May 25, 2026   doi: 10.1002/ajpa.70262   open full text
• Gender, Sex, and Health in Urban and Rural Late 19th‐Century New York State.
  Sharon N. DeWitte, Eric E. Jones, Emily J. Reardon, Annabelle J. Lewis.
  American Journal of Physical Anthropology. May 22, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nIndustrialization and urbanization have important effects on health that may vary within or between populations. We examine variation in health during agricultural commercialization, industrialization, and urbanization in 19th‐century rural Madison County and the city of Syracuse (Onondaga County) in New York State.\n\n\nMaterials and Methods\nWe use mortality data from New York State and Federal censuses, c. 1850–1880, to examine rural versus urban differences in health, and health outcomes by sex.\n\n\nResults\nWe find higher survivorship and lower hazards of death for older rural inhabitants (ages 45+), and lower rates of infectious disease deaths for older rural males compared to urban peers. We find similar survivorship and hazards of death for rural females and males, which may suggest exposure to similar risks and benefits, or the negative effects of rural environments for female health that counter their inherent physiological buffering. For urban inhabitants, we find worse outcomes for younger females compared to males (ages 15–44), which might reflect maternal mortality or occupational hazards. We find better outcomes for urban females past the age of 45, which might reflect selective mortality at younger ages or biological resilience.\n\n\nConclusions\nThese findings highlight the context‐dependent nature of health and suggest the intersection of biological and cultural factors in shaping health. Urban health disadvantages appear in this context to be driven by conditions among older men, and sex/gender differences in health and mortality are not uniform between the urban and rural populations. Future work will assess the mechanisms driving the variation we observe.\n\n"]

  May 22, 2026   doi: 10.1002/ajpa.70279   open full text
• Outpaced by Industry: Industrial Environments Reduce Endurance, With Implications for Evolutionary Fitness.
  Daniel P. Longman, Yvanna Todorova, Stephen J. Bailey, Nicolette C. Bishop, Molly Davidson, Julia Drewer, Ciara Dwyer, Lewis J. James, Yanzhe Li, Adelina Lintuluoto, Jonathan Millett, Vikki Neville, Fatin Sabrina Nor Azian, Matthew Putland, Toby Roberts, Mate Szazvai, Colin N. Shaw.
  American Journal of Physical Anthropology. May 20, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nPhysical function—the capacity to perform tasks requiring endurance and/or strength—is a key determinant of fitness that has directly influenced Homo sapiens' survival, reproduction and health throughout our evolutionary journey. However, the last 200–300 years of global industrialization has transformed human habitats at an unprecedented rate and may now be compromising key functions that underpin our fitness (Environmental Mismatch Hypothesis). Although industrialization has delivered a range of benefits, it has simultaneously introduced novel environmental challenges (e.g., air pollution, microplastics) and reduced contact with beneficial aspects of nature (e.g., phytoncides). While negative effects of industrialization have been demonstrated for other determinants of fitness, its impact on physical function remains almost completely unexplored.\n\n\nMaterials and Methods\nWe conducted a randomized, counterbalanced crossover study to determine whether brief exposure to an industrialized environment would impair endurance performance relative to a forest environment (used as a proxy for non‐industrial ancestral conditions). Twenty‐five healthy adults (19 females, 6 males) completed two test sessions, each involving a 90 min environmental exposure followed by a standardized laboratory cycling test of endurance.\n\n\nResults\nEndurance performance was significantly reduced following industrial exposure (time‐to‐exhaustion: 13.5 ± 0.9 min) compared to forest exposure (14.6 ± 1.0 min; p = 0.007). Industrial exposure also worsened mood and led to volitional exhaustion at a lower perceived exertion, while cardiorespiratory markers recorded during the endurance test (e.g., V̇O) did not differ significantly between conditions.\n\n\nConclusions\nThese results suggest that acute exposure to industrialized environments may reduce physical capacity, with potential consequences for evolutionary fitness.\n\n"]

  May 20, 2026   doi: 10.1002/ajpa.70270   open full text
• Whose Research Is It? Knowledge Creation With and for Adult Children of Survivors of the Genocide Against the Tutsi.
  Glorieuse Uwizeye, Zaneta M. Thayer, Julienne N. Rutherford.
  American Journal of Physical Anthropology. May 06, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\nDecolonial practices in bioanthropology have led to a shift toward intentional community engagement to inform the questions asked and the methods used, moving from “research on” to “research with”. Specifically, in our work with survivors of the genocide against the Tutsi, we have grappled with how to develop contextually and culturally adequate research processes that prioritize community ways of knowing in the context of intense, widescale trauma and tragedy. In this self‐reflexive narrative, we describe and reflect upon two stages of studies working with adult children of survivors of the genocide against the Tutsi. We provide the context of such work within the discipline of biological anthropology, and discuss the identities and relationships of the research team. The paper then shifts to a first‐person narrative by the first author, the Rwandan insider/outsider leader of the project, describing its evolution from investigator‐led observational quasi‐experimental research into integrative community‐based participatory research, detailing the ways in which engagement with the community has led to new questions and methodological approaches as the project continues to grow collaboratively. Rather than providing prescriptive guidelines for others committed to decolonizing their research programs, we use our experience to illustrate how such approaches necessarily vary across contexts and to highlight the importance of continued flexibility, reflexivity, and respect for community.\n"]

  May 06, 2026   doi: 10.1002/ajpa.70259   open full text
• Multisegment Model for Body Surface Area and Body Volume Estimation.
  Pavla A. Jarešová, Martin Hora, Michal Struška, Tobias L. Kordsmeyer, Julia Stern, Lars Penke, Vladimír Sládek.
  American Journal of Physical Anthropology. May 05, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nBody surface area (BSA) and body volume (BV) are crucial for understanding variations in body size and shape in humans. Direct measurement of BSA and BV is challenging due to the complex human body shape and variation in body proportion and composition among humans. To address these limitations, we developed a multisegment model for estimating BSA and BV.\n\n\nMaterials and Methods\nThe multisegment model of the human body divides the body into eight segments, each represented by geometric solids determined by linear dimensions. The trunk segment was represented as a circular base cylinder, an elliptical base cylinder, and a cuboid to determine the most accurate trunk representation. BSA and BV were computed by summing the surface areas and volumes of these geometric solids. The estimation error of our multisegment model and the previous models was tested using 60 3D whole‐body scans of males.\n\n\nResults\nModels with circular and cuboidal trunk shapes provide more accurate BSA estimates compared to the elliptical trunk model, while the cuboidal trunk model was the most accurate for BV estimation. Our cuboidal trunk model showed a similar estimation error for BSA but reduced the error for BV estimates by at least 5 percentage points compared to previously published models.\n\n\nDiscussion\nOur model stresses the importance of accurate representation of the trunk segment with three different representations. The estimate of BSA has better accuracy than the BV estimate. The model's overall accuracy highlights its potential for broader applications in anthropological and physiological research.\n\n"]

  May 05, 2026   doi: 10.1002/ajpa.70256   open full text
• Cranial Morphology of a 21,000‐Year‐Old Homo sapiens From Southwest China.
  Sungui Lin, Yuhao Zhao, Song Xing.
  American Journal of Physical Anthropology. May 05, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nThis study reports a new hominin cranium, dated to 21,000 years ago, offering novel insights into the evolutionary pattern of the cranial morphology of the East Asian Homo sapiens over the past 40,000 years.\n\n\nMaterials and Methods\nThe cranium (22IVPP‐H‐Cr01) was scanned and virtually reconstructed. Its morphology was described and compared primarily with other fossil H. sapiens. To better contextualize cranial variation, specimens of Homo heidelbergensis, East Asian late Middle Pleistocene archaic Homo, Homo neanderthalensis, and recent H. sapiens were also added to the comparative sample. Additionally, cranial measurements were conducted on the 22IVPP‐H‐Cr01 and compared with those of other taxonomic groups to assess its evolutionary status through principal component analysis.\n\n\nResults\nThe 22IVPP‐H‐Cr01 cranium represents a female aged ~35–40 years. It exhibits typical H. sapiens morphology while retaining ancestral traits, including pronounced prognathism, a broad interorbital region, and wide nasal aperture. Overall, the cranial configuration of 22IVPP‐H‐Cr01 appears more derived than pre‐LGM (Last Glacial Maximum) H. sapiens yet more primitive than post‐LGM H. sapiens in East Asia.\n\n\nDiscussion\nCompared to East Asian pre‐LGM H. sapiens, post‐LGM populations exhibit significant morphological variability. The 22IVPP‐H‐Cr01 specimen from Southwest China, dated to the LGM, may represent a candidate link between these two chronological groups. This finding supports population continuity at least in southern East Asia over the past 40,000 years, contrasting with the local population replacement documented in northern East Asia.\n\n"]

  May 05, 2026   doi: 10.1002/ajpa.70265   open full text
• Dental Microwear Texture Analysis of the Bornean Orangutans (Pongo pygmaeus) From the Selenka Collection.
  Sophie Gabriele Habinger, Gildas Merceron, Anneke H. van Heteren, Valeria Rojas Cuyutupa, Hervé Bocherens, Olivier Chavasseau.
  American Journal of Physical Anthropology. May 05, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nCharacterizing the diet of extant taxa is important not only to determine their ecological niche but also to serve as a reference for dietary and niche inferences in evolutionary studies. Tracking the diets of fossil taxa and their change through time has been increasingly employed to further understand the evolution of primates. In the last decades, several studies using stable isotope analysis, dental topography, or dental microwear analysis have been conducted to reconstruct the paleoecology and diet of fossil pongines. However, paleodietary reconstructions based on the dental microwear of fossil pongines lacked a well‐defined and extensive reference dataset of extant Pongo.\n\n\nMaterial and Methods\nTo close this gap, we characterized intrapopulation variation in dietary ecology using dental microwear textures of 89 orangutans collected by Emil and Margarethe Selenka on Borneo in 1894.\n\n\nResults\nOur study provides insights into dietary variation in extant Pongo and aims as an important reference dataset in future paleodietary reconstructions. According to climatic records available for the late 19th century, the specimens were not collected during an El Niño event; these events impact fruit resource abundance in Southeast Asia. We found no significant differences in dental microwear textures depending on sex, age, or locality.\n\n\nDiscussion\nThis suggests that, despite a large number of specimens and localities sampled, sex, age, and locality did not significantly influence the dietary resources consumed at the scale of the population. More detailed individual information—not available for this historical collection—would be necessary to further test these results.\n\n"]

  May 05, 2026   doi: 10.1002/ajpa.70266   open full text
• CSGM: A R Package to Conduct a Robust Cross‐Sectional Geometric Morphometric Analysis.
  Brian A. Keeling, Alessandro Urciuoli, Mercedes Conde‐Valverde, Julia Diez‐Valero, Laure Spake, Rolf Quam.
  American Journal of Physical Anthropology. May 04, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjective\nEvaluating the relationships between the shape and biomechanical function of bone cross‐sections can contribute novel insights towards human functional and evolutionary morphology. However, this research involves unique analytical and statistical challenges when comparing complex and multidimensional shape data to multivariate biomechanical variables. We developed the CSGM package in the R programming language to streamline statistical hypothesis testing on the geometric properties and shape of bone cross‐sections, offering unique interactive and informative visualization plots. This package uses a variety of popular statistical inferential techniques including correlation, covariation, classification, and prediction. By applying a novel nested hypothesis testing approach, users can efficiently analyze complex morphofunctional relationships in parallel.\n\n\nMaterials and Methods\nWe present various functions within the CSGM package that can analyze and visualize three‐dimensional shape relationships. In addition, we highlight dedicated functions which evaluate pairwise relationships between bone cross‐sectional shape and biomechanically relevant variables. The effectiveness of this automated hypothesis testing approach is demonstrated through the use of two associated, complex datasets generated from cross‐sections of the mandibular corpus in three modern human collections.\n\n\nResults\nThe functions of our package helped reveal prominent shape asymmetry in the study sample which also asymmetrically impacts the bending resistances and breaking strength properties of the mandibular corpus.\n\n\nDiscussion\nThe CSGM package offers a series of functions that can test morphofunctional relationships by incorporating a nested hypothesis modeling approach to statistical analysis and interactive graphic visualizations. Thus, CSGM is a useful and powerful analytical toolkit to interpret complex data relationships.\n\n"]

  May 04, 2026   doi: 10.1002/ajpa.70260   open full text
• Beyond Body Mass, Beyond Adulthood: The Ontogeny of Sexual Size Monomorphism.
  Gabrielle L. Bueno, Stacey R. Tecot, Rebecca J. Lewis.
  American Journal of Physical Anthropology. May 04, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nContest competition for mates and female reproductive energetics influence body size and sexual dimorphism across many primates; nevertheless, some monomorphic species defy these patterns. These deviations may reflect biological anthropology's focus on body mass and adult size as defining features of sexual dimorphism. Using ontogenetic data, we test whether sexual monomorphism in adult body mass necessitates monomorphism across all traits and evaluate whether mate competition and female energetics explain sex‐specific developmental patterns and adult morphology in a monomorphic primate.\n\n\nMaterials and Methods\nWe built sex‐specific growth curves using generalized additive mixed models to examine levels of sexual dimorphism in 14 morphological measurements across development in Verreaux's sifaka (Propithecus verreauxi) at Ankoatsifaka Research Station in western Madagascar.\n\n\nResults\nSifaka exhibited male‐biased dimorphism in upper arm and thigh circumference at adulthood and across growth, but not in other contest‐related traits. Adult females had significantly longer hindlimbs and thighs and exhibited bimaturism and increased growth rate in these and several other traits.\n\n\nDiscussion\nWe found limited support for our hypotheses that female reproductive energetics or male–male contest competition drive adult size, sex differences, and growth trajectories in Verreaux's sifaka. However, male–male contest competition likely drives male‐biased dimorphism in muscle mass, and longer female hindlimbs may represent an adaptation to infant carrying, reflecting a species‐specific suite of dimorphic traits. This study demonstrates that sexual dimorphism exists at finer scales even in monomorphic species, and that adult size and sex differences are the result of a mosaic of selective pressures acting on individual traits.\n\n"]

  May 04, 2026   doi: 10.1002/ajpa.70257   open full text
• Community‐Led Conservation of Endangered Primates in Southeastern Côte D'ivoire: Implications for Decolonizing African Primatology.
  Inza Koné, André Djaha Koffi, Elie Bandama Bogui, Didié Armand Zadou, Abenan Marie‐Ange Bénédicte Saleye.
  American Journal of Physical Anthropology. May 01, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\nThe Upper Guinean forests of West Africa are a major global hotspot for primate diversity, yet many areas remain understudied and insufficiently protected. Southeastern Côte d'Ivoire illustrates this conservation gap. Once home to several of West Africa's most threatened primate species, the region has experienced extensive deforestation, habitat fragmentation, and hunting pressure over recent decades. Consequently, many primate populations have declined or disappeared from large parts of their former range. The Tanoé‐Ehy Forest, a swamp forest ecosystem located along the Côte d'Ivoire–Ghana border, is now one of the last refuges for several endangered primates in the region. Since 2006, a long‐term conservation initiative led by Ivorian scientists, in partnership with local communities, has aimed to protect this forest and its biodiversity through a community‐based conservation approach. This article presents the Tanoé‐Ehy conservation initiative as a case study demonstrating how locally led conservation efforts can support both biodiversity protection and community empowerment while contributing to changes in conservation practice in African primatology. Over nearly two decades, the project has combined ecological research, participatory governance, and socio‐economic initiatives. Community members actively participate in wildlife monitoring, forest surveillance, environmental education, and livelihood diversification programs designed to reduce pressure on forest resources. Beyond biodiversity protection, the initiative highlights the importance of strengthening national scientific leadership and recognizing local communities as central actors in conservation governance. The Tanoé‐Ehy experience shows that effective and sustainable conservation in biodiversity‐rich regions depends on integrating local knowledge, equitable partnerships, and long‐term community engagement.\n"]

  May 01, 2026   doi: 10.1002/ajpa.70261   open full text
• Energetic Investment in Travel by Black Howler Monkeys: Testing Push–Pull Dynamics.
  Pedro A. D. Dias, Ariadna Rangel Negrín.
  American Journal of Physical Anthropology. April 30, 2026
  ["American Journal of Biological Anthropology, Volume 190, Issue 1, May 2026. ", "\nABSTRACT\n\nObjectives\nMovement decisions reflect trade‐offs between travel costs and expected benefits at the destination. We examined whether energetic investment in travel by black howler monkeys (Alouatta pigra), an energy‐limited species, is driven by push factors (departure conditions), pull factors (destination characteristics), or their integration.\n\n\nMaterials and Methods\nWe studied 12 groups in Campeche, Mexico (2005–2008), analyzing 7461 travel episodes from 59 adults (3747 observation hours). Energy expenditure was estimated using cost of transport models. We compared three model sets (push, pull, and combined) using mixed‐effects modeling.\n\n\nResults\nPull factors outperformed push and combined factors in explaining travel investment. Travel to unripe fruit trees required nearly twice the energy of travel to resting sites (492.4 vs. 245.0 J). Destination tree size increased costs by 11.9% per standard deviation increase in diameter, while travel to preferred food species required 5.7% less energy. Males expended 19.8% more energy per travel episode than females. Time of day showed a significant nonlinear effect, with costs decreasing asymmetrically across the day.\n\n\nDiscussion\nOur findings suggest that black howler monkeys prioritize destination characteristics over departure conditions when investing energy in travel, indicating goal‐directed rather than reactive movement despite their energy‐minimizing ecology. These results underscore the importance of quantifying energetic trade‐offs in travel decisions to understand how animals balance immediate costs against expected benefits, particularly in species where energy limitations constrain behavioral strategies.\n\n"]

  April 30, 2026   doi: 10.1002/ajpa.70263   open full text
• DNA methylation of methylation complex genes in relation to stress and genome‐wide methylation in mother–newborn dyads.
  Christopher J. Clukay, David A. Hughes, Nicole C. Rodney, Darlene A. Kertes, Connie J. Mulligan.
  American Journal of Physical Anthropology. October 13, 2017
  Objectives Early life stress is known to have enduring biological effects, particularly with respect to health. Epigenetic modifications, such as DNA methylation, are a possible mechanism to mediate the biological effect of stress. We previously found correlations between maternal stress, newborn birthweight, and genome‐wide measures of DNA methylation. Here we investigate ten genes related to the methylation/demethylation complex in order to better understand the impact of stress on health. Materials and methods DNA methylation and genetic variants at methylation/demethylation genes were assayed. Mean methylation measures were constructed for each gene and tested, in addition to genetic variants, for association with maternal stress measures based on interview and survey data (chronic stress and war trauma), maternal venous, and newborn cord genome‐wide mean methylation (GMM), and birthweight. Results After cell type correction, we found multiple pairwise associations between war trauma, maternal GMM, maternal methylation at DNMT1, DNMT3A, TET3, and MBD2, and birthweight. Conclusions The association of maternal GMM and maternal methylation at DNMT1, DNMT3A, TET3, and MBD2 is consistent with the role of these genes in establishing, maintaining and altering genome‐wide methylation patterns, in some cases in response to stress. DNMT1 produces one of the primary enzymes that reproduces methylation patterns during DNA replication. DNMT3A and TET3 have been implicated in genome‐wide hypomethylation in response to glucocorticoid hormones. Although we cannot determine the directionality of the genic and genome‐wide changes in methylation, our results suggest that altered methylation of specific methylation genes may be part of the molecular mechanism underlying the human biological response to stress.

  October 13, 2017   doi: 10.1002/ajpa.23341   open full text
• An anatomical and mechanical analysis of the douc monkey (genus Pygathrix), and its role in understanding the evolution of brachiation.
  C. D. Byron, M. C. Granatosky, H. H. Covert.
  American Journal of Physical Anthropology. October 11, 2017
  Objectives Pygathrix is an understudied Asian colobine unusual among the Old World monkeys for its use of arm‐swinging. Little data exists on the anatomy and mechanics of brachiation in this genus. Here, we consider this colobine to gain insight into the parallel evolution of suspensory behavior in primates. Materials and methods This study compares axial and appendicular morphological variables of Pygathrix with other Asian colobines. Additionally, to assess the functional consequences of Pygathrix limb anatomy, kinematic and kinetic data during arm‐swinging are included to compare the douc monkey to other suspensory primates (Ateles and Hylobates). Results Compared to more pronograde species, Pygathrix and Nasalis share morphology consistent with suspensory locomotion such as its narrower scapulae and elongated clavicles. More distally, Pygathrix displays a gracile humerus, radius, and ulna, and shorter olecranon process. During suspensory locomotion, Pygathrix, Ateles, and Hylobates all display mechanical convergence in limb loading and movements of the shoulder and elbow, but Pygathrix uses pronated wrist postures that include substantial radial deviation during arm‐swinging. Discussion The adoption of arm‐swinging represents a major shift within at least three anthropoid clades and little data exist about its transition. Across species, few mechanical differences are observed during arm‐swinging. Apparently, there are limited functional solutions to the challenges associated with moving bimanually below branches, especially in more proximal forelimb regions. Morphological data support this idea that the Pygathrix distal forelimb differs from apes more than its proximal end. These results can inform other studies of ape evolution, the pronograde to orthograde transition, and the convergent ways in which suspensory locomotion evolved in primates.

  October 11, 2017   doi: 10.1002/ajpa.23320   open full text
• Further consideration of the curvature of the Neandertal Femur.
  Tara Chapman, Victor Sholukha, Patrick Semal, Stéphane Louryan, Serge Van Sint Jan.
  American Journal of Physical Anthropology. October 11, 2017
  Objectives Neandertal femora are particularly known for having a marked sagittal femoral curvature. This study examined femoral curvature in Neandertals in comparison to a modern human population from Belgium by the use of three‐dimensional (3D) quadric surfaces modeled from the bone surface. 3D models provide detailed information and enabled femoral curvature to be analyzed in conjunction with other morphological parameters. Materials and Methods 3D models were created from CT scans of 75 modern human femora and 7 Neandertal femora. Quadric surfaces (QS) were created from the triangulated surface vertices in all areas of interest (neck, head, diaphyseal shaft, condyles) extracted from previously placed anatomical landmarks. The diaphyseal shaft was divided into five QS shapes and curvature was measured by degrees of difference between QS shapes. Each bone was placed in a local coordinate system enabling each bone to be analyzed in the same way. Results The use of 3D quadric surface fitting allowed the distribution of curvature with similarly curved femora to be analyzed and the different patterns of curvature between the two groups to be determined. The Neandertals were shown to have a higher degree of femoral curvature and a more distal point of femoral curvature than the modern human population from Belgium. Conclusions Morphological aspects of the Neandertal femur are different from this modern human population although mainly seem unrelated to femoral curvature. The relative lack of correlations with other femoral bony morphological factors suggests femoral curvature variations may be related to other aspects.

  October 11, 2017   doi: 10.1002/ajpa.23334   open full text
• Ethnic derivation of the Ainu inferred from ancient mitochondrial DNA data.
  Noboru Adachi, Tsuneo Kakuda, Ryohei Takahashi, Hideaki Kanzawa‐Kiriyama, Ken‐ichi Shinoda.
  American Journal of Physical Anthropology. October 11, 2017
  Objectives The Ainu, the indigenous people living on the northernmost island of Japan, Hokkaido, have long been a focus of anthropological interest because of their cultural, linguistic, and physical identity. A major problem with genetic studies on the Ainu is that the previously published data stemmed almost exclusively from only 51 modern‐day individuals living in Biratori Town, central Hokkaido. To clarify the actual genetic characteristics of the Ainu, individuals who are less influenced by mainland Japanese, who started large‐scale immigration into Hokkaido about 150 years ago, should be examined. Moreover, the samples should be collected from all over Hokkaido. Materials and methods Mitochondrial DNA haplogroups of 94 Ainu individuals from the Edo era were successfully determined by analyzing haplogroup‐defining polymorphisms in the hypervariable and coding regions. Thereafter, their frequencies were compared to those of other populations. Results Our findings indicate that the Ainu still retain the matrilineage of the Hokkaido Jomon people. However, the Siberian influence on this population is far greater than previously recognized. Moreover, the influence of mainland Japanese is evident, especially in the southwestern part of Hokkaido that is adjacent to Honshu, the main island of Japan. Discussion Our results suggest that the Ainu were formed from the Hokkaido Jomon people, but subsequently underwent considerable admixture with adjacent populations. The present study strongly recommends revision of the widely accepted dual‐structure model for the population history of the Japanese, in which the Ainu are assumed to be the direct descendants of the Jomon people.

  October 11, 2017   doi: 10.1002/ajpa.23338   open full text
• Dental microwear textural analysis as an analytical tool to depict individual traits and reconstruct the diet of a primate.
  Alice M. Percher, Gildas Merceron, Gontran Nsi Akoue, Jordi Galbany, Alejandro Romero, Marie JE Charpentier.
  American Journal of Physical Anthropology. October 09, 2017
  Objectives Dental microwear is a promising tool to reconstruct animals' diet because it reflects the interplay between the enamel surface and the food items recently consumed. This study examines the sources of inter‐individual variations in dietary habits in a free‐ranging population of mandrills (Mandrillus sphinx) using a combination of feeding monitoring and in vivo dental microwear textural analysis (DMTA). Methods We investigated the impact of seasonality and individual traits on four DMTA parameters. In parallel, we further studied the influence of the physical properties of the food items consumed on these four parameters, using three proxies (mechanical properties, estimates of phytolith and external grit contents). Results We found that seasonality, age, and sex all impact DMTA parameters but those results differ depending on the facet analyzed (crushing vs. shearing facets). Three DMTA parameters (anisotropy, complexity, and heterogeneity of complexity) appear sensitive to seasonal variations and anisotropy also differs between the sexes while textural fill volume tends to vary with age. Moreover, the physical properties of the food items consumed vary seasonally and also differ depending on individual sex and age. Conclusion Considering the interplay between the tested variables and both dental microwear and diet, we reaffirm that food physical properties play a major role in microwear variations. These results suggest that DMTA parameters may provide valuable hints for paleoecological reconstruction using fragmentary fossil dental remains.

  October 09, 2017   doi: 10.1002/ajpa.23337   open full text
• Forearm pronation efficiency in A.L. 288‐1 (Australopithecus afarensis) and MH2 (Australopithecus sediba): Insights into their locomotor and manipulative habits.
  Pere Ibáñez‐Gimeno, Joan Manyosa, Ignasi Galtés, Xavier Jordana, Salvador Moyà‐Solà, Assumpció Malgosa.
  American Journal of Physical Anthropology. September 26, 2017
  Objectives The locomotor and manipulative abilities of australopithecines are highly debated in the paleoanthropological context. Australopithecus afarensis and Australopithecus sediba likely engaged in arboreal locomotion and, especially the latter, in certain activities implying manipulation. Nevertheless, their degree of arboreality and the relevance of their manipulative skills remain unclear. Here we calculate the pronation efficiency of the forearm (Erot) in these taxa to explore their arboreal and manipulative capabilities using a biomechanical approach. Materials and methods Three‐dimensional humeral images and upper limb measurements of A.L. 288‐1 (Au. afarensis) and MH2 (Au. sediba) were used to calculate Erot using a previously described biomechanical model. Results Maximal Erot in elbow flexion occurs in a rather supinated position of the forearm in Au. afarensis, similarly to Pan troglodytes. In elbow extension, maximal Erot in this fossil taxon occurs in the same forearm position as in Pongo spp. In Au. sediba the forearm positions where Erot is maximal are largely coincident with those for Hylobatidae. Conclusions The pattern in Au. afarensis suggests relevant arboreal capabilities, which would include vertical climbing, although it is suggestive of poorer manipulative skills than in modern humans. The similarity between Au. sediba and Hylobatidae is difficult to interpret, but the differences between Au. sediba and Au. afarensis suggest that the capacity to rotate the forearm followed different evolutionary processes in these australopithecine species. Although functional inferences from the upper limb are complex, the observed differences between both taxa point to the existence of two distinct anatomical models.

  September 26, 2017   doi: 10.1002/ajpa.23319   open full text
• The development of feeding behavior in wild chimpanzees (Pan troglodytes schweinfurthii).
  Joel Bray, Melissa Emery Thompson, Martin N. Muller, Richard W. Wrangham, Zarin P. Machanda.
  American Journal of Physical Anthropology. September 26, 2017
  Objectives Primates have an extended period of juvenility before adulthood. Although dietary complexity plays a prominent role in hypotheses regarding the evolution of extended juvenility, the development of feeding behavior is still poorly understood. Indeed, few studies have investigated the timing and nature of feeding transitions in apes, including chimpanzees. We describe general patterns of feeding development in wild chimpanzees and evaluate predictions of the needing‐to‐learn hypothesis. Materials and Methods We analyzed 4 years of behavioral data (2010–2013) from 26 immature chimpanzees and 31 adult chimpanzees of the Kanyawara community in Kibale National Park, Uganda. Specifically, we examined milestones of nutritional independence (first consumption of solid food and cessation of suckling) as well as developmental changes in feeding time, diet composition, diet breadth, and ingestion rates. Results Chimpanzees first fed on solid food at 5.1 months and, on average, suckled until 4.8 years. Daily feeding time of immature individuals reached adult levels between 4 and 6 years, while diet composition showed minor changes with age. By juvenility (5–10 years), individuals had a complete adult diet breadth. Ingestion rates for five ripe fruit species remained below adult levels until juvenility but continued to show absolute increases into adolescence. Discussion Chimpanzees acquired adult‐like patterns on all feeding measures by infancy or juvenility. These data are inconsistent with the needing‐to‐learn hypothesis; moreover, where delays exist, alternatives hypotheses make similar predictions but implicate physical constraints rather than learning as causal factors. We outline predictions for how future studies might distinguish between hypotheses for the evolution of extended juvenility.

  September 26, 2017   doi: 10.1002/ajpa.23325   open full text
• External and internal ontogenetic changes in the first rib.
  Daniel García‐Martínez, Orosia García Gil, Oscar Cambra‐Moo, María Canillas, Miguel A. Rodríguez, Markus Bastir, Armando González Martín.
  American Journal of Physical Anthropology. September 23, 2017
  Objectives First ribs bear information about thorax morphology and are usually well preserved, compared to other ribs, in bone/fossil samples. Several studies have addressed ontogeny of the first rib by studying changes in bone microanatomy and rib morphology separately, but no studies have combined both approaches to study how internal and external changes covary during ontogeny. The aim of this project is to fill this gap in our knowledge. Materials and methods We applied 3D geometric morphometrics of sliding semilandmarks to 14 first ribs of Homo sapiens to quantify rib curvature and mid‐shaft cross‐section outline. Ontogenetic variation was addressed throughout a principal component analysis (PCA). Additionally, we made histological sections at the mid‐shaft of the same ribs and studied tissue matrix composition and compartmentalization. Finally, we performed partial least squares (PLS) and regression analyses to study covariation between rib morphology and compartmentalization variables. Results PCA shows that first ribs increase their curvature over the course of ontogeny and the rib midshaft becomes less rounded during ontogeny. In addition, the sternal end becomes more medially oriented during ontogeny and the relative head‐tubercle distance becomes longer. Compartmentalization shows a decrease in the area occupied by mineralized tissues and an increase in the area occupied by non‐mineralized tissues over the course of ontogeny, which covaries with mid‐shaft cross‐section shape. Conclusions Our results show detailed variation in rib morphology along with histological changes in bone tissue compartmentalization and, for the first time, the correlation between the two. This could be related to muscle attachments on the 1st rib and also to changes in breathing mode, from diaphragmatic in perinatals to pulmonary in adults, which could also have implications for understanding thorax evolution.

  September 23, 2017   doi: 10.1002/ajpa.23313   open full text
• Manual function and performance in humans, gorillas, and orangutans during the same tool use task.
  Ameline Bardo, Raphaël Cornette, Antony Borel, Emmanuelle Pouydebat.
  American Journal of Physical Anthropology. September 23, 2017
  Objectives Humans are known to possess more complex manual abilities than other primates. However, the manual abilities of primates have not been fully explored, and we still do not know if the manipulative abilities we attribute to humans are unique. The aim of this study was to compare the manual function and performance developed by humans, gorillas and orangutans while performing the same experimental tool use task. Materials and Methods The study was conducted on 20 humans, 6 gorillas, and 7 orangutans. Each individual had to use a tool to collect food from a maze during six experimental sessions while maintaining the same unconstrained body posture condition. We quantified the different manual techniques used and the manual performance. Results Each species used different techniques. Humans used bimanual grip techniques, pad‐to‐pad precision grasping postures, and in‐hand movements involving fingertips. Gorillas used unimanual grip techniques and simple in‐hand movements while orangutans used a variety of strategies (e.g., hand or mouth). With these techniques, humans performed the task better than both gorillas and orangutans (e.g., by being quicker to collect the food). Discussion This study highlights other ways in which humans’ manual dexterity differs from that of other species and emphasizes the distinct manipulative function of orangutans. The differences between the species could be due to the differing muscular anatomy and morphology of the hands, with hand proportion possibly placing particular biomechanical constraints on each species. The differences between gorillas and orangutans could result from their different locomotor behaviors, and we hypothesize terrestriality facilitates the development of complex manipulation.

  September 23, 2017   doi: 10.1002/ajpa.23323   open full text
• Femoral neck‐shaft angle and climate‐induced body proportions.
  Stephanie L. Child, Libby W. Cowgill.
  American Journal of Physical Anthropology. September 23, 2017
  Objectives Declination in femoral neck‐shaft angle (NSA) is commonly linked to an increased level of physical activity during life. More recently, however, research suggests that lower NSA might also be explained, in part, as the mechanical consequence of differences in ecogeographic body proportions. This study tests the proposed link between NSA and climatic‐induced body proportions, using relative body mass (RBM), throughout the course of development. Materials and Methods NSA and RBM were collected for 445 immature remains from five geographic locations. NSA and RBM were standardized for age‐effects. ANOVA was used to examine when population differences emerged in both NSA and RBM. Regression analyses were used to examine the pattern of relationship between NSA and RBM. Results Populations differ significantly in NSA and RBM before skeletal maturity, and these differences occur early in life. While both NSA and RBM change over the course of development, no significant relationship was found between NSA and RBM for any sample, or any age category (p = .244). Discussion Individuals who have relatively greater relative body mass do not necessarily have lower NSA. Population differences in NSA were found to be variable, while differences in RBM remained consistent across the developmental span. Taken together, these results suggest that regardless of body proportions, the degree of declination of NSA is presumed to be similar among individuals with similar gait and ambulatory behaviors. Conversely, populations differ in RBM from birth, and these differences are consistent throughout development. These two measures likely are responsive to diffing stimuli, and any potential relationship is likely complex and multifactorial.

  September 23, 2017   doi: 10.1002/ajpa.23311   open full text
• The effect of leprotic infection on the risk of death in medieval rural Denmark.
  K. Saige Kelmelis, Michael Holton Price, Jim Wood.
  American Journal of Physical Anthropology. September 22, 2017
  Introduction Paleopathological studies of leprosy in Danish skeletal collections show that many individuals suffered from this stigmatized disease during the Middle Ages. This study examines the risk of death associated with leprotic infection in individuals from the Danish rural cemetery of Øm Kloster (AD 1172–1536). Specifically, we modeled the influence of leprotic infection on age‐specific mortality accounting also for sex and social status (lay person / monastic). Materials and methods The sample consisted of 311 adult individuals from the Øm Kloster skeletal collection housed at the Institute of Forensic Medicine, University of Southern Denmark (ADBOU). We modeled morbidity and mortality using a three‐state illness‐death model with the following parameterizations for the three transition hazards: (1) nonlesioned to lesioned: constant; (2) nonlesioned to dead: Gompertz‐Makeham; and (3) lesioned to dead: Gompertz‐Makeham, directly proportional to the hazard of the well to dead transition. Results The mortality hazard of lesioned individuals exceeded that of nonlesioned individuals by a factor of 1.4 (40%) across all individuals, 1.7 for females, 1.0 for males, 1.3 for lay persons, and 1.7 for monastics. Overall, 15% of the sample died with skeletal manifestations of leprosy, though it is likely that a higher percentage of the population carried the bacterium. Discussion This study improves understanding of past health and population dynamics focusing on a chronic infectious disease. The methods employed could informatively be applied to larger analyses of community health from skeletal collections by incorporating more than one disease into the multistate model and inferring individual frailty using various skeletal markers.

  September 22, 2017   doi: 10.1002/ajpa.23314   open full text
• Testing support for the northern and southern dispersal routes out of Africa: an analysis of Levantine and southern Arabian populations.
  Deven N. Vyas, Ali Al‐Meeri, Connie J. Mulligan.
  American Journal of Physical Anthropology. September 15, 2017
  Objectives The Northern Dispersal Route (NDR) and Southern Dispersal Route (SDR) are hypothesized to have been used by modern humans in the dispersal out of Africa. The NDR follows the Nile into Northeast Africa and crosses the Red Sea into the Levant. The SDR emerges from the Horn of Africa and crosses the Bab el‐Mandeb into southern Arabia. In this study, we analyze genetic data from populations living along the NDR and SDR to test support for each dispersal route. Materials and methods We genotyped 90 Yemeni samples on the Affymetrix Human Origins array. We analyzed these data with published data from Levantine and other southern Arabian populations as well as 157 comparative populations for a total sample size of >550,000 genetic variants from >2,000 individuals in >160 populations. We calculated outgroup f3 statistics to test how Levantine and southern Arabian populations relate to African populations living along the NDR and SDR and to other non‐African populations. Results We find that Levantine and southern Arabian populations bear similar genetic relationships to both African and non‐African populations, thus providing no support for the use of one dispersal route over the other. Discussion Our results are consistent with a history of gene flow between the Levant and southern Arabia. Consideration of genetic, archaeological, and paleoclimate data provide a slight edge for the SDR but, ultimately, more data are needed to definitively identify which dispersal route out of Africa was used.

  September 15, 2017   doi: 10.1002/ajpa.23312   open full text
• Age at reproductive debut: Developmental predictors and consequences for lactation, infant mass, and subsequent reproduction in rhesus macaques (Macaca mulatta).
  Florent Pittet, Crystal Johnson, Katie Hinde.
  American Journal of Physical Anthropology. September 12, 2017
  Objectives The age at which females initiate their reproductive career is a critical life‐history parameter with potential consequences on their residual reproductive value and lifetime fitness. The age at reproductive debut may be intimately tied to the somatic capacity of the mother to rear her young, but relatively little is known about the influence of age of first birth on milk synthesis within a broader framework of reproductive scheduling, infant outcomes, and other life‐history tradeoffs. Material and Methods Our study investigated the predictors of age at first reproduction among 108 captive rhesus macaque (Macaca mulatta) females, and associations with their milk synthesis at peak lactation, infant mass, and ability to subsequently conceive and reproduce. Results The majority of females reproduced in their fourth year (typical breeders); far fewer initiated their reproductive career one year earlier or one year later (respectively early and late breeders). Early breeders (3‐year‐old) benefited from highly favorable early life development (better juvenile growth, high dominance rank) to accelerate reproduction, but were impaired in milk synthesis due to lower somatic resources and their own continued growth. Comparatively, late breeders suffered from poor developmental conditions, only partially compensated by their delayed reproduction, and evinced compromised milk synthesis. Typical breeders not only produced higher available milk energy but also had best reproductive performance during the breeding and birth seasons following primiparity. Discussion Here, we refine and extend our understanding of how life‐history tradeoffs manifest in the magnitude, sources, and consequences of variation in age of reproductive debut. These findings provide insight into primate reproductive flexibility in the context of constraints and opportunities.

  September 12, 2017   doi: 10.1002/ajpa.23286   open full text
• Cranial sexual dimorphism in the Kinda baboon (Papio hamadryas kindae).
  Michelle Singleton, Brielle C. Seitelman, Joseph R. Krecioch, Stephen R. Frost.
  American Journal of Physical Anthropology. September 06, 2017
  Objectives The smallest extant member of genus Papio, the Kinda baboon exhibits low sexual dimorphism and a distinctive cranial shape. Ontogenetic scaling accounts for most cranial‐shape differences within Papio, but studies have shown that the Kinda follows a separate ontogenetic trajectory. If so, its cranial‐dimorphism pattern should differ from other subspecies. To evaluate this hypothesis, morphometric analysis was used to investigate cranial dimorphism in Papio. Materials and methods Three‐dimensional landmarks were digitized on 434 adult crania representing six Papio subspecies. Size‐ and shape‐dimorphism magnitudes were quantified using centroid size and Procrustes distances. Patterns of sex‐ and size‐related variation were explored using MAN(C)OVA, multivariate regression, and form‐space PCA. Canine dimorphism was investigated using dental metrics. Results Kinda size and shape dimorphism are significantly lower than in other Papio subspecies. The relative magnitude of Kinda shape dimorphism is similar to other southern baboons; Kinda canine dimorphism is unremarkable. MAN(C)OVA results support subspecies differences in cranial dimorphism and scaling. Allometric and dimorphism vectors differ significantly in some subspecies, and their vector‐angle matrices are strongly correlated. The Kinda's allometric vector angles are divergent. Form‐space PC3, summarizing size‐independent dimorphism, separates the Kinda from other subspecies. Discussion The Kinda baboon exhibits significantly lower size and shape dimorphism than other baboons, but its relative dimorphism levels are unexceptional. The Kinda differs from other subspecies in patterns of allometry, size‐related shape dimorphism, and residual shape dimorphism. Kinda facial shape is “masculinized” relative to size, especially in females, suggesting female sexual selection contributed to the evolution of Kinda dimorphism.

  September 06, 2017   doi: 10.1002/ajpa.23304   open full text
• Transition to agriculture in South‐Eastern Arabia: Insights from oral conditions.
  Olivia Munoz.
  American Journal of Physical Anthropology. September 06, 2017
  Objectives In Southeast (SE) Arabia, agriculture is supposed to expand around 3000 BC, but its tempo and its actual role in populations' subsistence is still debated by archaeologists. Here, we compare dental health conditions of 11 skeletal samples from coastal and inland sites, dated from the Late Neolithic (ca. 4500–3100 BC) to the Early Bronze Age (EBA), conventionally divided into Hafit (ca. 3100–2700 BC) and Umm an‐Nar period (ca. 2700–2000 BC). The goal is to assess long‐term trends in subsistence patterns and regional variability during the local transition to agriculture. Methods Seven indicators of oral health and childhood stress were analyzed, including dental wear, calculus, caries, alveolar resorption, periapical lesions, ante‐mortem tooth loss (AMTL), and linear enamel hypoplasia (LEH). Results Neolithic coastal populations are globally characterized by high dental wear, high calculus frequency, high LEH frequency, and frequent periodontal disease, whereas they exhibit low abscesses and AMTL frequencies and a total absence of carious lesions. Samples from the Hafit period present high dental wear, low rates of calculus and LEH, frequent periodontal disease, combined with low abscess and AMTL frequencies and absence of caries. By contrast, samples from the Umm an‐Nar period exhibit much lower dental wear, calculus and LEH rates, whereas caries, periapical lesions and AMTL frequencies increase significantly. Marked differences were observed between coastal and inland Umm an‐Nar groups, the latter presenting significantly higher frequencies of caries, periapical lesions, alveolar resorption and AMTL. Discussion/Conclusion Oral conditions from the Neolithic coastal populations denote a diet mainly composed of unprocessed and abrasive food, with high protein and low carbohydrate intakes, and frequent stress episodes. Although Hafit populations display some changes in oral pathologies, which indicate modifications in their lifestyle and a diversification of the diet, no markers of high carbohydrate intakes were observed in our samples. The impact of agriculture on oral health appears clearly only from the Umm an‐Nar period, and is more intense inland than on the coast, where marine resources are still a main component of the diet.

  September 06, 2017   doi: 10.1002/ajpa.23307   open full text
• Comparison of hand use and forelimb posture during vertical climbing in mountain gorillas (Gorilla beringei beringei) and chimpanzees (Pan troglodytes).
  Johanna Neufuss, Martha M. Robbins, Jana Baeumer, Tatyana Humle, Tracy L. Kivell.
  American Journal of Physical Anthropology. September 05, 2017
  Objectives Studies on grasping and limb posture during arboreal locomotion in great apes in their natural environment are scarce and thus, attempts to correlate behavioral and habitat differences with variation in morphology are limited. The aim of this study is to compare hand use and forelimb posture during vertical climbing in wild, habituated mountain gorillas (Gorilla beringei beringei) and semi‐free‐ranging chimpanzees (Pan troglodytes) to assess differences in the climbing styles that may relate to variation in hand or forelimb morphology and body size. Materials and methods We investigated hand use and forelimb posture during both ascent and descent vertical climbing in 15 wild mountain gorillas and eight semi‐free‐ranging chimpanzees, using video records obtained ad libitum. Results In both apes, forelimb posture was correlated with substrate size during both ascent and descent climbing. While climbing, both apes used power grips and diagonal power grips, including three different thumb postures. Mountain gorillas showed greater ulnar deviation of the wrist during vertical descent than chimpanzees, and the thumb played an important supportive role when gorillas vertically descended lianas. Discussion We found that both apes generally had the same grip preferences and used similar forelimb postures on supports of a similar size, which is consistent with their overall similarity in hard and soft tissue morphology of the hand and forelimb. However, some species‐specific differences in morphology appear to elicit slightly different grasping strategies during vertical climbing between mountain gorillas and chimpanzees.

  September 05, 2017   doi: 10.1002/ajpa.23303   open full text
• Predictors of insubordinate aggression among captive female rhesus macaques.
  Shannon K. Seil, Darcy L. Hannibal, Brianne A. Beisner, Brenda McCowan.
  American Journal of Physical Anthropology. August 21, 2017
  Objectives Cercopithicine primates tend to have nepotistic hierarchies characterized by predictable, kinship‐based dominance. Although aggression is typically directed down the hierarchy, insubordinate aggression does occur. Insubordination is important to understand because it can precipitate social upheaval and undermine group stability; however, the factors underlying it are not well understood. We test whether key social and demographic variables predict insubordination among captive female rhesus macaques. Materials and Methods To identify factors influencing insubordination, multivariate analyses of 10,821 dyadic conflicts among rhesus macaque females were conducted, using data from six captive groups. A segmented regression analysis was used to identify dyads with insubordination. Negative binomial regression analyses and an information theoretic approach were used to assess predictors of insubordination among dyads. Results In the best models, weight difference (w = 1.0; IRR = 0.930), age (dominant: w = 1.0, IRR = 0.681; subordinate: w = 1.0, IRR = 1.069), the subordinate's total number of allies (w = 0.727, IRR = 1.060) or non‐kin allies (w = 0.273, IRR = 1.165), the interaction of the dominant's kin allies and weight difference (w = 0.938, IRR = 1.046), violation of youngest ascendancy (w = 1.0; IRR = 2.727), and the subordinate's maternal support (w = 1.0; IRR = 2.928), are important predictors of insubordination. Discussion These results show that both intrinsic and social factors influence insubordinate behavior. This adds to evidence of the importance of intrinsic factors and flexibility in a social structure thought to be rigid and predetermined by external factors. Further, because insubordination can precipitate social overthrow, determining predictors of insubordination will shed light on mechanisms underlying stability in nepotistic societies.

  August 21, 2017   doi: 10.1002/ajpa.23296   open full text
• The characteristic mid‐shaft cross‐sectional shape of the ulna in Jomon hunter‐gatherers.
  Yasuo Hagihara, Takashi Nara.
  American Journal of Physical Anthropology. August 21, 2017
  Objectives The Jomon people were hunter‐gatherers who inhabited the Japanese archipelago between 10,000 BC and 300 BC. Here, we focus on the mid‐shaft cross‐sectional shape of the ulna in the Jomon population and compare it with modern Japanese people. Materials and methods Jomon specimens, including 32 males and 22 females, were excavated from shell mound sites in the Pacific and Seto inland coastal area of Honshu island in the Japanese archipelago dated to the Late‐to‐Final Jomon phase (between 2,000 BC and 300 BC). Mid‐shaft ulna cross‐sectional shapes were compared with modern Japanese specimens (25 males, 21 females) using standard linear measurements and elliptic Fourier analysis (EFA). Differences from both sides of this element were compared using predicted handedness. Results Linear measurements and EFA results show that ulna shape of both sexes within the Jomon population are relatively larger in the antero‐posterior direction and have more developed posterior borders than modern Japanese males and females. No significant differences were observed between Jomon sexes based on the predicted dominant side, but differences were evident in the predicted nondominant side. At the same time, bilateral differences were recognized in Jomon females, because of a lower level of posterior border development in the predicted nondominant side compared to the dominant side. Discussion Shape differences between Jomon people and modern Japanese can be explained by variation in the habitual loading of the ulna. Sexual dimorphism in ulna shape within the Jomon population suggests division of labor differences.

  August 21, 2017   doi: 10.1002/ajpa.23300   open full text
• Energetic cost of walking in fossil hominins.
  M. Vidal‐Cordasco, A. Mateos, G. Zorrilla‐Revilla, O. Prado‐Nóvoa, J. Rodríguez.
  American Journal of Physical Anthropology. August 19, 2017
  Objective Many biomechanical studies consistently show that a broader pelvis increases the reaction forces and bending moments across the femoral shaft, increasing the energetic costs of unloaded locomotion. However, a biomechanical model does not provide the real amount of metabolic energy expended in walking. The aim of this study is to test the influence of pelvis breadth on locomotion cost and to evaluate the locomotion efficiency of extinct Pleistocene hominins. Material and Methods The current study measures in vivo the influence of pelvis width on the caloric cost of locomotion, integrating anthropometry, body composition and indirect calorimetry protocols in a sample of 46 subjects of both sexes. Results We show that a broader false pelvis is substantially more efficient for locomotion than a narrower one and that the influence of false pelvis width on the energetic cost is similar to the influence of leg length. Two models integrating body mass, femur length and bi‐iliac breadth are used to estimate the net and gross energetic costs of locomotion in a number of extinct hominins. The results presented here show that the locomotion of Homo was not energetically more efficient than that of Australopithecus and that the locomotion of extinct Homo species was not less efficient than that of modern Homo sapiens. Discussion The changes in the anatomy of the pelvis and lower limb observed with the appearance of Homo ergaster probably did not fully offset the increased expenditure resulting from a larger body mass. Moreover, the narrow pelvis in modern humans does not contribute to greater efficiency of locomotion.

  August 19, 2017   doi: 10.1002/ajpa.23301   open full text
• A test of the optimal iron hypothesis among breastfeeding Ariaal mothers in northern Kenya.
  Masako Fujita, Katherine Wander.
  American Journal of Physical Anthropology. August 19, 2017
  Objective The optimal iron hypothesis posits a trade‐off in iron nutrition—iron deficiency restricts iron available to infectious agents, protecting against severe infection, but also compromises immune defense—such that mild‐to‐moderate iron deficiency may be more adaptive than either iron‐replete or severe deficiency in environments with high infectious disease load. This hypothesis has not been tested among adults. Materials and Methods A secondary analysis of data and specimens from 220 lactating mothers in northern Kenya was conducted. Elevated serum C‐reactive protein (CRP > 2 or >5 mg/l) was utilized to identify prevalent subclinical infection/inflammation. Iron deficiency was identified with transferrin receptor in archived dried blood spots (TfR > 5.0 mg/l). The absence of iron deficiency or anemia (Hemoglobin < 12 g/l) defined the iron replete state. Iron‐deficient erythropoiesis (IDE, mild‐to‐moderate iron deficiency) was defined as iron deficiency without anemia; iron deficiency anemia (IDA, severe iron deficiency) as iron deficiency with anemia; and noniron‐deficiency anemia (NIDA) as anemia without iron deficiency. Results The prevalence of elevated inflammation (subclinical infection) was lowest in IDE. In logistic regression, IDE was inversely associated with inflammation (for CRP > 2 mg/l: adjusted odds ratio, aOR = 0.30; p = 0.02; for CRP > 5 mg/l: aOR = 0.27; p = 0.10), compared to the iron replete state. The protective effect of IDE differed in the presence of vitamin A deficiency or underweight. Conclusions We interpret these patterns as tentative support for the optimal iron hypothesis in breastfeeding women in the infectious disease ecology of northern Kenya. Iron deficiency may interact in important ways with other forms of malnutrition that are known to affect immune protection.

  August 19, 2017   doi: 10.1002/ajpa.23299   open full text
• Variation in human gape cycle kinematics and occlusal topography.
  Myra F. Laird.
  American Journal of Physical Anthropology. August 19, 2017
  Objectives This study tested hypotheses relating intraspecific variation in occlusal morphology and intraspecific variation in jaw movements during feeding. Gape cycle kinematic variation was hypothesized to correlate with gape cycle number within a chewing sequence as well as with food toughness and stiffness. Gape cycle kinematic variation was also hypothesized to correlate with variation in occlusal area, slope, and volume. Methods and Materials Twenty‐six adult human subjects chewed four foods with varying material properties while their jaw movements were recorded using three‐dimensional coordinates of facial markers captured with a Vicon camera system. Post‐canine occlusal morphology of each subject was quantified in ArcGIS using dental topographic analysis of dental casts. Results Gape cycle duration did not vary with gape cycle number, food toughness, or food stiffness. Gape cycle vertical and lateral displacement correlated negatively with gape cycle number, while foods with higher toughness and Young's modulus had greater jaw vertical and lateral displacement. Subjects with steeper occlusal slopes had longer gape cycle durations and greater amounts of vertical displacement during the slow closing phase of the gape cycle. Discussion The results suggest that gape cycle durations are relatively consistent despite changes in food properties and gape cycle number, while occlusal slope affects gape cycle duration and vertical displacement during inferred occlusal contact. However, gape cycle number and bolus properties explain greater amounts of kinematic variation than does occlusal morphology.

  August 19, 2017   doi: 10.1002/ajpa.23298   open full text
• Heritability and genetic integration of tooth size in the South Carolina Gullah.
  Christopher M. Stojanowski, Kathleen S. Paul, Andrew C. Seidel, William N. Duncan, Debbie Guatelli‐Steinberg.
  American Journal of Physical Anthropology. August 19, 2017
  Objectives This article provides estimates of narrow‐sense heritability and genetic pleiotropy for mesiodistal tooth dimensions for a sample of 20th century African American individuals. Results inform biological distance analysis and offer insights into patterns of integration in the human dentition. Materials and Methods Maximum mesiodistal crown dimensions were measured using Hillson‐FitzGerald calipers on 469 stone dental casts from the Menegaz‐Bock Collection. Narrow‐sense heritability estimates and genetic and phenotypic correlations were estimated using SOLAR 8.1.1 with covariate screening for age, sex, age*sex interaction, and birth year. Results Heritability estimates were moderate (∼0.10 – 0.90; h2 mean = 0.51) for most measured variables with sex as the only significant covariate. Patterns of genetic correlation indicate strong integration across tooth classes, except molars. Comparison of these results to previously published work suggests lower overall heritability relative to other human populations and much stronger genetic integration across tooth classes than obtained from nonhuman primate genetic pleiotropy estimates. Conclusions These results suggest that the high heritabilities previously published may reflect overestimates inherent in previous study designs; as such the standard estimate of 0.55 used in biodistance analyses may not be appropriate. For the Gullah, isolation and endogamy coupled with elevated levels of physiological and economic stress may suppress narrow‐sense heritability estimates. Pleiotropy analyses suggest a more highly integrated dentition in humans than in other mammals.

  August 19, 2017   doi: 10.1002/ajpa.23290   open full text
• Relative tooth size at birth in primates: Life history correlates.
  Timothy D. Smith, Magdalena N. Muchlinski, Wade R. Bucher, Christopher J. Vinyard, Christopher J. Bonar, Sian Evans, Lawrence E. Williams, Valerie B. DeLeon.
  American Journal of Physical Anthropology. August 19, 2017
  Objectives Dental eruption schedules have been closely linked to life history variables. Here we examine a sample of 50 perinatal primates (28 species) to determine whether life history traits correlate with relative tooth size at birth. Materials and methods Newborn primates were studied using serial histological sectioning. Volumes of deciduous premolars (dp2–dp4), replacement teeth (if any), and permanent molars (M1–2/3) of the upper jaw were measured and residuals from cranial length were calculated with least squares regressions to obtain relative dental volumes (RDVs). Results Relative dental volumes of deciduous or permanent teeth have an unclear relationship with relative neonatal mass in all primates. Relative palatal length (RPL), used as a proxy for midfacial size, is significantly, positively correlated with larger deciduous and permanent postcanine teeth. However, when strepsirrhines alone are examined, larger RPL is correlated with smaller RDV of permanent teeth. In the full sample, RDVs of deciduous premolars are significantly negatively correlated with relative gestation length (RGL), but have no clear relationship with relative weaning age. RDVs of molars lack a clear relationship with RGL; later weaning is associated with larger molar RDV, although correlations are not significant. When strepsirrhines alone are analyzed, clearer trends are present: longer gestations or later weaning are associated with smaller deciduous and larger permanent postcanine teeth (only gestational length correlations are significant). Discussion Our results indicate a broad trend that primates with the shortest RGLs precociously develop deciduous teeth; in strepsirrhines, the opposite trend is seen for permanent molars. Anthropoids delay growth of permanent teeth, while strepsirrhines with short RGLs are growing replacement teeth concurrently. A comparison of neonatal volumes with existing information on extent of cusp mineralization indicates that growth of tooth germs and cusp mineralization may be selected for independently.

  August 19, 2017   doi: 10.1002/ajpa.23302   open full text
• Patterns and prevalence of violence‐related skull trauma in medieval London.
  Kathryn Krakowka.
  American Journal of Physical Anthropology. August 09, 2017
  Objectives This study aims to identify the patterns and prevalence of violence‐related skull trauma (including the cranium and mandible) among a large sample of skeletons from medieval London (1050–1550 AD). Materials and Methods In total, data from 399 skulls, representing six different sites from across medieval London, were analyzed for evidence of trauma and assessed for the likelihood that it was caused by violence. The sites include the three parish cemeteries of St Nicholas Shambles (GPO75), St Lawrence Jewry (GYE92), and St Benet Sherehog (ONE94); the two monastic houses of London Blackfriars (PIC87) and St Mary Graces (MIN86); and the early inmate cemetery from the medieval hospital of St Mary Spital (NRT85). Results The overall findings suggest that violence affected all aspects of medieval London society, but how that violence was characterized largely depended on sex and burial location. Specifically, males from the lay cemeteries appear to have been the demographic most affected by violence‐related skull injuries, particularly blunt force trauma to the cranial vault. Discussion Using both archaeological and historical evidence, the results suggest that violence in medieval London may have been more prevalent than in other parts of medieval England, particularly rural environments, but similar to other parts of medieval Europe. However, more studies focusing on medieval trauma, and violence specifically, need to be carried out to further strengthen these results. In particular, males from the lay cemeteries were disproportionately affected by violence‐related trauma, especially blunt force trauma. It perhaps indicates a means of informal conflict resolution as those of lower status did not always have the newly established medieval legal system available to them.

  August 09, 2017   doi: 10.1002/ajpa.23288   open full text
• OH 83: A new early modern human fossil cranium from the Ndutu beds of Olduvai Gorge, Tanzania.
  Whitney B. Reiner, Fidelis Masao, Sabrina B. Sholts, Agustino Venance Songita, Ian Stanistreet, Harald Stollhofen, R.E. Taylor, Leslea J. Hlusko.
  American Journal of Physical Anthropology. August 08, 2017
  Objective Herein we introduce a newly recovered partial calvaria, OH 83, from the upper Ndutu Beds of Olduvai Gorge, Tanzania. We present the geological context of its discovery and a comparative analysis of its morphology, placing OH 83 within the context of our current understanding of the origins and evolution of Homo sapiens. Materials and methods We comparatively assessed the morphology of OH 83 using quantitative and qualitative data from penecontemporaneous fossils and the W.W. Howells modern human craniometric dataset. Results OH 83 is geologically dated to ca. 60–32 ka. Its morphology is indicative of an early modern human, falling at the low end of the range of variation for post‐orbital cranial breadth, the high end of the range for bifrontal breadth, and near average in frontal length. Discussion There have been numerous attempts to use cranial anatomy to define the species Homo sapiens and identify it in the fossil record. These efforts have not met wide agreement by the scientific community due, in part, to the mosaic patterns of cranial variation represented by the fossils. The variable, mosaic pattern of trait expression in the crania of Middle and Late Pleistocene fossils implies that morphological modernity did not occur at once. However, OH 83 demonstrates that by ca. 60–32 ka modern humans in Africa included individuals that are at the fairly small and gracile range of modern human cranial variation.

  August 08, 2017   doi: 10.1002/ajpa.23292   open full text
• Post‐weaning diet in archaeological human populations: A meta‐analysis of carbon and nitrogen stable isotope ratios of child skeletons.
  Takumi Tsutaya.
  American Journal of Physical Anthropology. August 08, 2017
  Objectives Childhood is a unique stage in human life history, in which subadults have completed their weaning process but are still dependent on older individuals for survival. Although the importance of food provisioning during childhood has been intensively discussed, childhood diet in the past has rarely been studied in a systematic manner. Methods In this study, a meta‐analysis of carbon and nitrogen stable isotope ratios of post‐weaning children (PWC) in Holocene human populations around the world is presented. The isotope ratios of PWC were standardized with those of adult females and males in the same population, and they were analyzed in terms of the difference in subsistence. Results Results of this study indicate that diets of PWC and adults were generally similar (most differences were within the range of ±1‰), which is consistent with the universal feature of food provisioning to PWC in humans. In hunter—gatherer populations, there is no significant difference between PWC and adult isotope ratios. In non‐hunter—gatherer populations, however, PWC probably consumed significantly larger proportions of foods from lower trophic levels than did the adults, and such foods would be terrestrial C3 plants. Conclusions Potential factors relating to the dietary differences among PWC and adults are presented from a perspective of balance between food provisioning and self‐acquisition by PWC. Significant isotopic differences between PWC and adults in non‐hunter—gatherer populations revealed in this study have implications for declined health during the subsistence transition in Holocene, isotopic studies using human tooth enamel, and “δ15N dip” of subadults after weaning.

  August 08, 2017   doi: 10.1002/ajpa.23295   open full text
• The genetic admixture in Tibetan‐Yi Corridor.
  Hong‐Bing Yao, Senwei Tang, Xiaotian Yao, Hui‐Yuan Yeh, Wanhu Zhang, Zhiyan Xie, Qiajun Du, Liying Ma, Shuoyun Wei, Xue Gong, Zilong Zhang, Quanfang Li, Bingying Xu, Hu‐Qin Zhang, Gang Chen, Chuan‐Chao Wang.
  American Journal of Physical Anthropology. August 07, 2017
  Objectives The Tibetan‐Yi Corridor located on the eastern edge of Tibetan Plateau is suggested to be the key region for the origin and diversification of Tibeto‐Burman speaking populations and the main route of the peopling of the Plateau. However, the genetic history of the populations in the Corridor is far from clear due to limited sampling in the northern part of the Corridor. Materials and methods We collected blood samples from 10 Tibetan and 10 Han Chinese individuals from Gansu province and genotyped about 600,000 genome‐wide single nucleotide polymorphisms (SNPs). Results Our data revealed that the populations in the Corridor are all admixed on a genetic cline of deriving ancestry from Tibetans on the Plateau and surrounding lowland East Asians. The Tibetan and Han Chinese groups in the north of the Plateau show significant evidence of low‐level West Eurasian admixture that could be probably traced back to 600∼900 years ago. Discussion We conclude that there have been huge population migrations from surrounding lowland onto the Tibetan Plateau via the Tibetan‐Yi Corridor since the initial formation of Tibetans probably in Neolithic Time, which leads to the current genetic structure of Tibeto‐Burman speaking populations.

  August 07, 2017   doi: 10.1002/ajpa.23291   open full text
• Land use and mobility during the Neolithic in Wales explored using isotope analysis of tooth enamel.
  Samantha Neil, Janet Montgomery, Jane Evans, Gordon T. Cook, Chris Scarre.
  American Journal of Physical Anthropology. July 28, 2017
  Objectives The nature of land use and mobility during the transition to agriculture has often been debated. Here, we use isotope analysis of tooth enamel from human populations buried in two different Neolithic burial monuments, Penywyrlod and Ty Isaf, in south‐east Wales, to examine patterns of land use and to evaluate where individuals obtained their childhood diet. Materials and Methods We employ strontium (87Sr/86Sr) and oxygen (δ18O) and carbon (δ13C) isotope analysis of enamel from adjacent molars. We compare strontium isotope values measured in enamel to locally bioavailable 87Sr/86Sr values. We combine discussion of these results with evaluation of new radiocarbon dates obtained from both sites. Results The majority of enamel samples from Penywyrlod have strontium isotope ratios above 0.7140. In contrast, the majority of those from Ty Isaf have 87Sr/86Sr values below 0.7140. At Penywyrlod oxygen isotope ratios range between 25.9 and 28.2 ‰ (mean 26.7 ± 0.6 ‰, 1σ, n = 15) and enamel δ13Ccarbonate values range between −18.0 and −15.0 ‰ (mean −16.0 ± 0.8 ‰, 1σ, n = 15). At Ty Isaf oxygen isotope ratios exhibited by Neolithic individuals range between 25.4 and 27.7 ‰ (mean 26.7 ± 0.6 ‰, 1σ, n = 15) and enamel δ13Ccarbonate values range between −16.9 and −14.9 ‰ (mean −16.0 ± 0.6 ‰, 1σ, n = 15). Discussion The strontium isotope results suggest that the majority of individuals buried at Penywyrlod did not source their childhood diet locally. One individual in this group has strontium isotope ratios that exceed all current known biosphere values within England and Wales. This individual is radiocarbon dated to the first few centuries of the 4th millennium BC, consistent with the period in which agriculture was initiated in Wales: the results therefore provide evidence for migration during the transition to farming in Wales. In contrast, all individuals sampled from Ty Isaf post‐date the period in which agriculture is considered to have been initiated and could have sourced their childhood diet from the local region in which they were buried.

  July 28, 2017   doi: 10.1002/ajpa.23279   open full text
• Malnutrition‐related early childhood exposures and enamel defects in the permanent dentition: A longitudinal study from the Bolivian Amazon.
  Erin E. Masterson, Annette L. Fitzpatrick, Daniel A. Enquobahrie, Lloyd A. Mancl, Esther Conde, Philippe P. Hujoel.
  American Journal of Physical Anthropology. July 28, 2017
  Objectives We investigated the relationship between early childhood malnutrition‐related measures and subsequent enamel defects in the permanent dentition. Materials and Methods This cohort study included 349 Amerindian adolescents (10–17 years, 52% male) from the Bolivian Amazon. Exposures included: stunted growth (height‐for‐age z‐scores), underweight (weight‐for‐age z‐scores), anemia (hemoglobin), acute inflammation (C‐reactive protein) and parasitic infection (hookworm). We measured the occurrence (no/yes) and extent (<1/3, 1/3–2/3, >2/3) of enamel defects. We estimated associations between childhood exposures and enamel defect measures using log‐binomial and multinomial logistic regression. Results The prevalence of an enamel defect characterized by an orange peel texture on a large central depression on the labial surface of the central maxillary incisors was 92.3%. During childhood (1–4 years), participants had a high prevalence of stunted growth (75.2%), anemia (56.9%), acute inflammation (39.1%), and hookworm infection (49.6%). We observed associations between childhood height‐for‐age (OR = 0.65; P = 0.028 for >2/3 extent vs. no EH) and gastrointestinal hookworm infection (OR = 3.43; P = 0.035 for >2/3 extent vs. no defects or <1/3 extent) with enamel defects. Discussion The study describes a possibly novel form of enamel hypoplasia and provides evidence for associations of malnutrition‐related measures in early childhood, including stunted growth and parasitic helminth infection, with the observed enamel defects.

  July 28, 2017   doi: 10.1002/ajpa.23283   open full text
• A craniometric analysis of early modern Romania and Hungary: The roles of migration and conversion in shaping European Ottoman population history.
  Kathryn Grow Allen, Noreen von Cramon‐Taubadel.
  American Journal of Physical Anthropology. July 27, 2017
  Objectives Debate persists regarding the biological makeup of European Ottoman communities settled during the expansion of the Ottoman Empire during the 16th and 17th centuries, and the roles of conversion and migration in shaping demography and population history. The aim of this study was to perform an assessment of the biological affinities of three European Ottoman series based on craniometric data. Materials and Methods Craniometric data collected from three Ottoman series from Hungary and Romania were compared to European and Anatolian comparative series, selected to represent biological affinity representative of historically recorded migration and conversion influences. Sex‐separated samples were analyzed using D2‐matrices, along with principal coordinates and PERMANOVA analyses to investigate biological affinities. Discriminant function analysis was employed to assign Ottoman individuals to two potential classes: European or Anatolian. Results Affinity analyses show larger than expected biological differences between males and females within each of the Ottoman communities. Discriminant function analyses show that the majority of Ottoman individuals could be classified as either European or Anatolian with a high probability. Moreover, location within Europe proved influential, as the Ottomans from a location of more geopolitical importance (Budapest) diverged from more hinterland communities in terms of biological affinity patterns. Discussion The results suggest that male and female Ottomans may possess distinct population histories, with males and females divergent from each other in terms of their biological affinities. The Ottoman communities appear diverse in terms of constituting a mix of peoples from different biological backgrounds. The greater distances between sexes from the same community, and the differences between communities, may be evidence that the processes of migration and conversion impacted individual people and groups diversely.

  July 27, 2017   doi: 10.1002/ajpa.23287   open full text
• Internal diversification of non‐Sub‐Saharan haplogroups in Sahelian populations and the spread of pastoralism beyond the Sahara.
  Iva Kulichová, Verónica Fernandes, Alioune Deme, Jana Nováčková, Vlastimil Stenzl, Andrea Novelletto, Luísa Pereira, Viktor Černý.
  American Journal of Physical Anthropology. July 24, 2017
  Background Today, African pastoralists are found mainly in the Sahel/Savannah belt spanning 6,000 km from west to east, flanked by the Sahara to the north and tropical rainforests to the south. The most significant group among them are the Fulani who not only keep cattle breeds of possible West Eurasian ancestry, but form themselves a gene pool containing some paternally and maternally‐transmitted West Eurasian haplogroups. Materials and Methods We generated complete sequences for 33 mitogenomes belonging to haplogroups H1 and U5 (23 and 10, respectively), and genotyped 16 STRs in 65 Y chromosomes belonging to haplogroup R1b‐V88. Results We show that age estimates of the maternal lineage H1cb1, occurring almost exclusively in the Fulani, point to the time when the first cattle herders settled the Sahel/Savannah belt. Similar age estimates were obtained for paternal lineage R1b‐V88, which occurs today in the Fulani but also in other, mostly pastoral populations. Maternal clade U5b1b1b, reported earlier in the Berbers, shows a shallower age, suggesting another possibly independent input into the Sahelian pastoralist gene pool. Conclusions Despite the fact that animal domestication originated in the Near East ∼ 10 ka, and that it was from there that animals such as sheep, goats as well as cattle were introduced into Northeast Africa soon thereafter, contemporary cattle keepers in the Sahel/Savannah belt show uniparental genetic affinities that suggest the possibility of an ancient contact with an additional ancestral population of western Mediterranean ancestry.

  July 24, 2017   doi: 10.1002/ajpa.23285   open full text
• Neandertal talus bones from El Sidrón site (Asturias, Spain): A 3D geometric morphometrics analysis.
  Antonio Rosas, Anabel Ferrando, Markus Bastir, Antonio García‐Tabernero, Almudena Estalrrich, Rosa Huguet, Daniel García‐Martínez, Juan Francisco Pastor, Marco de la Rasilla.
  American Journal of Physical Anthropology. July 17, 2017
  Objectives The El Sidrón tali sample is assessed in an evolutionary framework. We aim to explore the relationship between Neandertal talus morphology and body size/shape. We test the hypothesis 1: talar Neandertal traits are influenced by body size, and the hypothesis 2: shape variables independent of body size correspond to inherited primitive features. Materials and methods We quantify 35 landmarks through 3D geometric morphometrics techniques to describe H. neanderthalensis‐H. sapiens shape variation, by Mean Shape Comparisons, Principal Component, Phenetic Clusters, Minimum spanning tree analyses and partial least square and regression of talus shape on body variables. Shape variation correlated to body size is compared to Neandertals‐Modern Humans (MH) evolutionary shape variation. The Neandertal sample is compared to early hominins. Results Neandertal talus presents trochlear hypertrophy, a larger equality of trochlear rims, a shorter neck, a more expanded head, curvature and an anterior location of the medial malleolar facet, an expanded and projected lateral malleolar facet and laterally expanded posterior calcaneal facet compared to MH. Discussion The Neandertal talocrural joint morphology is influenced by body size. The other Neandertal talus traits do not co‐vary with it or not follow the same co‐variation pattern as MH. Besides, the trochlear hypertrophy, the trochlear rims equality and the short neck could be inherited primitive features; the medial malleolar facet morphology could be an inherited primitive feature or a secondarily primitive trait; and the calcaneal posterior facet would be an autapomorphic feature of the Neandertal lineage.

  July 17, 2017   doi: 10.1002/ajpa.23280   open full text
• 2,000 Year old β‐thalassemia case in Sardinia suggests malaria was endemic by the Roman period.
  Claudia Viganó, Cordula Haas, Frank J. Rühli, Abigail Bouwman.
  American Journal of Physical Anthropology. July 06, 2017
  Objectives The island of Sardinia has one of the highest incidence rates of β‐thalassemia in Europe due to its long history of endemic malaria, which, according to historical records, was introduced around 2,600 years ago by the Punics and only became endemic around the Middle Ages. In particular, the cod39 mutation is responsible for more than 95% of all β‐thalassemia cases observed on the island. Debates surround the origin of the mutation. Some argue that its presence in the Western Mediterranean reflects the migration of people away from Sardinia, others that it reflects the colonization of the island by the Punics who might have carried the disease allele. The aim of this study was to investigate β‐globin mutations, including cod39, using ancient DNA (aDNA) analysis, to better understand the history and origin of β‐thalassemia and malaria in Sardinia. Materials and Methods PCR analysis followed by sequencing were used to investigate the presence of β‐thalassemia mutations in 19 individuals from three different Roman and Punic necropolises in Sardinia. Results The cod39 mutation was identified in one male individual buried in a necropolis from the Punic/Roman period. Further analyses have shown that his mitochondrial DNA (mtDNA) and Y‐chromosome haplogroups were U5a and I2a1a1, respectively, indicating the individual was probably of Sardinian origin. Conclusions This is the earliest documented case of β‐thalassemia in Sardinia to date. The presence of such a pathogenic mutation and its persistence until present day indicates that malaria was likely endemic on the island by the Roman period, earlier than the historical sources suggest.

  July 06, 2017   doi: 10.1002/ajpa.23278   open full text
• Diet of the prehistoric population of Rapa Nui (Easter Island, Chile) shows environmental adaptation and resilience.
  Catrine L. Jarman, Thomas Larsen, Terry Hunt, Carl Lipo, Reidar Solsvik, Natalie Wallsgrove, Cassie Ka'apu‐Lyons, Hilary G. Close, Brian N. Popp.
  American Journal of Physical Anthropology. June 30, 2017
  Objectives The Rapa Nui “ecocide” narrative questions whether the prehistoric population caused an avoidable ecological disaster through rapid deforestation and over‐exploitation of natural resources. The objective of this study was to characterize prehistoric human diets to shed light on human adaptability and land use in an island environment with limited resources. Materials and methods Materials for this study included human, faunal, and botanical remains from the archaeological sites Anakena and Ahu Tepeu on Rapa Nui, dating from c. 1400 AD to the historic period, and modern reference material. We used bulk carbon and nitrogen isotope analyses and amino acid compound specific isotope analyses (AA‐CSIA) of collagen isolated from prehistoric human and faunal bone, to assess the use of marine versus terrestrial resources and to investigate the underlying baseline values. Similar isotope analyses of archaeological and modern botanical and marine samples were used to characterize the local environment. Results Results of carbon and nitrogen AA‐CSIA independently show that around half the protein in diets from the humans measured came from marine sources; markedly higher than previous estimates. We also observed higher δ15N values in human collagen than could be expected from the local environment. Discussion Our results suggest highly elevated δ15N values could only have come from consumption of crops grown in substantially manipulated soils. These findings strongly suggest that the prehistoric population adapted and exhibited astute environmental awareness in a harsh environment with nutrient poor soils. Our results also have implications for evaluating marine reservoir corrections of radiocarbon dates.

  June 30, 2017   doi: 10.1002/ajpa.23273   open full text
• Using demographic characteristics of populations to detect spatial fragmentation following suspected ebola outbreaks in great apes.
  Céline Genton, Romane Cristescu, Sylvain Gatti, Florence Levréro, Elodie Bigot, Peggy Motsch, Pascaline Le Gouar, Jean‐Sébastien Pierre, Nelly Ménard.
  American Journal of Physical Anthropology. June 29, 2017
  Objectives Demographic crashes due to emerging diseases can contribute to population fragmentation and increase extinction risk of small populations. Ebola outbreaks in 2002–2004 are suspected to have caused a decline of more than 80% in some Western lowland gorilla (Gorilla gorilla gorilla) populations. We investigated whether demographic indicators of this event allowed for the detection of spatial fragmentation in gorilla populations. Materials and Methods We collected demographic data from two neighbouring populations: the Lokoué population, suspected to have been affected by an Ebola outbreak (followed from 2001 to 2014), and the Romani population, of unknown demographic status before Ebola outbreaks (followed from 2005 to 2014). Results Ten years after the outbreak, the Lokoué population is slowly recovering and the short‐term demographic indicators of a population crash were no longer detectable. The Lokoué population has not experienced any additional demographic perturbation over the past decade. The Romani population did not show any of the demographic indicators of a population crash over the past decade. Its demographic structure remained similar to that of unaffected populations. Discussion Our results highlighted that the Ebola disease could contribute to fragmentation of gorilla populations due to the spatially heterogeneous impact of its outbreaks. The demographic structure of populations (i.e., age‐sex and group structure) can be useful indicators of a possible occurrence of recent Ebola outbreaks in populations without known history, and may be more broadly used in other emerging disease/species systems. Longitudinal data are critical to our understanding of the impact of emerging diseases on wild populations and their conservation.

  June 29, 2017   doi: 10.1002/ajpa.23275   open full text
• Resource intensification and osteoarthritis patterns: changes in activity in the prehistoric Sacramento‐San Joaquin Delta region.
  Colleen M. Cheverko, Eric J. Bartelink.
  American Journal of Physical Anthropology. June 27, 2017
  Objectives Ethnohistoric accounts and archaeological research from Central California document a shift from the use of lower‐cost, high‐ranked resources (e.g., large game) toward the greater use of higher‐cost, low‐ranked resources (e.g., acorns and small seeds) during the Late Holocene (4500–200 BP). The subsistence transition from higher consumption of large game toward an increased reliance on acorns was likely associated with increases in levels of logistical mobility and physical activity. This study predicts that mobility and overall workload patterns changed during this transition to accommodate new food procurement strategies and incorporate new dietary resources during the Late Holocene in Central California. Materials and Methods Osteoarthritis prevalence was scored in the shoulder, elbow, hip, and knee of adult individuals (n = 256) from seven archaeological sites in the Sacramento‐San Joaquin Delta region. Comparisons were made between osteoarthritis prevalence, sex, age‐at‐death, and time period using ANCOVAs. Results The results of this study indicate significant increases in osteoarthritis prevalence in the hip of adult males and females during the Late Period (1200–200 BP), even after correcting for the cumulative effects of age. No differences were observed between the sexes or between time periods for the shoulder, elbow, and knee joints. Discussion The temporal increase in hip osteoarthritis supports the hypothesis that there was an increasing need for greater logistical mobility over time to procure key resources away from the village sites. Additionally, the lack of sex differences in osteoarthritis prevalence may suggest that females and males likely performed similar levels of activity during these periods.

  June 27, 2017   doi: 10.1002/ajpa.23272   open full text
• Resolving relationships between several Neolithic and Mesolithic populations in Northern Eurasia using geometric morphometrics.
  Ekaterina Stansfield (Bulygina), Anna Rasskasova, Natalia Berezina, Andrei D. Soficaru.
  American Journal of Physical Anthropology. June 22, 2017
  Objectives Remains from several Eastern European and Siberian Mesolithic and Neolithic sites are analysed to clarify their biological relationships. We assume that groups' geographical distances correlate with genetic and, therefore, morphological distances between them. Materials and Methods Material includes complete male crania from several Mesolithic and Neolithic burial sites across Northern Eurasia and from several modern populations. Geometric morphometrics and multivariate statistical techniques are applied to explore morphological trends, group distances, and correlations with their geographical position, climate, and the time of origin. Results Despite an overlap in the morphology among the modern and archeological groups, some of them show significant morphological distances. Geographical parameters account for only a small proportion of cranial variation in the sample, with larger variance explained by geography and age together. Expectations of isolation by distance are met in some but not in all cases. Climate accounts for a large proportion of autocorrelation with geography. Nearest‐neighbor joining trees demonstrate group relationships predicted by the regression on geography and on climate. Discussion The obtained results are discussed in application to relationships between particular groups. Unlike the Ukrainian Mesolithic, the Yuzhny Oleni Ostrov Mesolithic displays a high morphological affinity with several groups from Northern Eurasia of both European and Asian origin. A possibility of a common substrate for the Yuzhny Oleni Ostrov Mesolithic and Siberian Neolithic groups is reviewed. The Siberian Neolithic is shown to have morphological connection with both modern Siberian groups and the Native North Americans.

  June 22, 2017   doi: 10.1002/ajpa.23264   open full text
• Measuring fitness heritability: Life history traits versus morphological traits in humans.
  Alina Gavrus‐Ion, Torstein Sjøvold, Miguel Hernández, Rolando González‐José, María Esther Esteban Torné, Neus Martínez‐Abadías, Mireia Esparza.
  American Journal of Physical Anthropology. June 21, 2017
  Objectives Traditional interpretation of Fisher's Fundamental Theorem of Natural Selection is that life history traits (LHT), which are closely related with fitness, show lower heritabilities, whereas morphological traits (MT) are less related with fitness and they are expected to show higher heritabilities. In humans, although few studies have examined the heritability of LHT and MT, none of them have analyzed the same sample for comparative purposes. Here we assessed, for the first time, the heritability, additive genetic variance (VA), residual variance (VR) and coefficient of genetic additive variation (CVA) values of LHT and MT in a singular collection of identified skulls with associated demographic records from Hallstatt (Austria). Materials and Methods LHT, such as lifespan, number of offspring, age at birth of first and last child, reproductive span, and lifetime reproductive success, were estimated from 18,134 individuals from the Hallstatt Catholic parish records, which represent seven generations and correspond to a time span of 400 years. MT were assessed through 17 craniofacial indices and 7 angles obtained from 355 adult crania from the same population. Heritability, VA, VR, and CVA values of LHT and MT were calculated using restricted maximum likelihood methods. Results LHT heritabilities ranged from 2.3 to 34% for the whole sample, with men showing higher heritabilities (4–45%) than women (0‐23.7%). Overall, MT presented higher heritability values than most of LHT, ranging from 0 to 40.5% in craniofacial indices, and from 13.8 to 32.4% in craniofacial angles. LHT showed considerable additive genetic variance values, similar to MT, but also high environmental variance values, and most of them presenting a higher evolutionary potential than MT. Discussion Our results demonstrate that, with the exception of lifespan, LHT show lower heritability values, than MT. The lower heritability of LHT is explained by a higher influence of environmental and cultural factors.

  June 21, 2017   doi: 10.1002/ajpa.23271   open full text
• Geographic substructure in craniometric estimates of admixture for contemporary American populations.
  Bridget F. B. Algee‐Hewitt.
  American Journal of Physical Anthropology. June 21, 2017
  Objectives This study investigates heterogeneity in craniometrically‐derived estimates of admixture in order to reveal population substructure in a sample of Black, White, Hispanic, and Native American individuals from the FDB. It reports evidence of spatial trends in population‐specific patterns of admixture and contextualizes its results in terms of demographic diversity in the United States. Materials and Methods The FDB was sampled to capture the population variation within forensic casework, skeletal collections, and the U.S. population‐at‐large. Individuals were selected for the availability of population identifier, sex, and geographic information. Variation in inferred admixture proportions was evaluated, per population and by sex, for evidence of geographic substructure. Comparative data was sourced from the U.S. Census. Results This analysis identifies significant associations between the estimated Black, Native American and White component memberships and place of birth and recovery. The sampled populations differ significantly in admixture proportions, in a systematic way. Admixture patterns vary in accordance with the densities and relative proportions of the U.S. census populations. Discussion There is considerable variation in admixture estimates, not just between, but notably within, all four of the populations. This substructure can be explained by differences in geography, including regions, divisions, and states. This article's findings agree with census trends and speak broadly to admixture dynamics and ancestral diversity among contemporary Americans. They are also specifically relevant to those cases in the FDB. The presence of subpopulations has implications for cranial research, forensic identification, and studies of biological variation in the United States.

  June 21, 2017   doi: 10.1002/ajpa.23267   open full text
• Scale of human mobility in the southern Andes (Argentina and Chile): A new framework based on strontium isotopes.
  Ramiro Barberena, Víctor A Durán, Paula Novellino, Diego Winocur, Anahí Benítez, Augusto Tessone, María N Quiroga, Erik J Marsh, Alejandra Gasco, Valeria Cortegoso, Gustavo Lucero, Carina Llano, Kelly J Knudson.
  American Journal of Physical Anthropology. June 20, 2017
  Objectives The goal of this article is to assess the scale of human paleomobility and ecological complementarity between the lowlands and highlands in the southern Andes during the last 2,300 years. By providing isotope results for human bone and teeth samples, we assess a hypothesis of “high residential mobility” suggested on the basis of oxygen isotopes from human remains. Methods We develop an isotopic assessment of human mobility in a mountain landscape combining strontium and oxygen isotopes. We analyze bone and teeth samples as an approach to life‐history changes in spatial residence. Human samples from the main geological units and periods within the last two millennia are selected. Results We present a framework for the analysis of bioavailable strontium based on the combination of the geological data with isotope results for rodent samples. The 87Sr/86Sr values from human samples indicate residential stability within geological regions along life history. When comparing strontium and oxygen values for the same human samples, we record a divergent pattern: while δ18O values for samples from distant regions overlap widely, there are important differences in 87Sr/86Sr values. Conclusions Despite the large socio‐economic changes recorded, 87Sr/86Sr values indicate a persisting scenario of low systematic mobility between the different geological regions. Our results suggest that strontium isotope values provide the most germane means to track patterns of human occupation of distinct regions in complex geological landscapes, offering a much higher spatial resolution than oxygen isotopes in the southern Andes.

  June 20, 2017   doi: 10.1002/ajpa.23270   open full text
• Region‐dependent patterns of trabecular bone growth in the human proximal femur: A study of 3D bone microarchitecture from early postnatal to late childhood period.
  Petar Milovanovic, Danijela Djonic, Michael Hahn, Michael Amling, Björn Busse, Marija Djuric.
  American Journal of Physical Anthropology. June 20, 2017
  Objectives Parallel with body growth and development, bone structure in non‐adults is reorganized to achieve the particular design observed in mature individuals. We traced the changes in three‐dimensional trabecular microarchitectural design during the phases of locomotor maturation to clarify how human bone adapts to mechanical demands. Materials and Methods Micro‐CT was performed on biomechanically‐relevant subregions of the proximal femur (medial, intermediate and lateral neck regions, intertrochanteric region, metaphyseal region) from early postnatal period to late childhood. Results Developmental patterns of trabecular microarchitecture showed that gestationally overproduced bone present at birth underwent the most dramatic reduction during the first year, followed by a reversing trend in some of the quantitative parameters (e.g., bone volume fraction, trabecular anisotropy). Certain regional anisotropy already present at birth is further accentuated into the childhood suggesting an adaptation to differential loading environments. Trabecular eccentricity in the femoral neck was particularly accentuated during childhood, giving the medial neck—the site mostly loaded in walking—superior microarchitectural design (high bone volume fraction and anisotropy, the earliest appearance and predominance of plate‐ and honeycomb‐shaped trabeculae). Discussion While providing quantitative data on how bone microarchitecture adapts to increasing mechanical demands occurring during the phases of locomotor maturation, the study reveals how regional anisotropy develops in the proximal femur to ensure a functional and competent bone structure. Decomposing the region‐specific patterns of bone mass accrual is important in understanding skeletal adaptations to bipedalism, as well for understanding why fractures often occur location‐dependent, both in pediatric and elderly individuals.

  June 20, 2017   doi: 10.1002/ajpa.23268   open full text
• Comparative performance of deciduous and permanent dental morphology in detecting biological relatives.
  Kathleen S. Paul, Christopher M. Stojanowski.
  American Journal of Physical Anthropology. June 19, 2017
  Objectives Dental morphology plays a key role in reconstructing population history and evolutionary relationships at global, regional, and intracemetery scales. At the inter‐individual level, it is assumed that close biological kin exhibit greater phenotypic similarity than non‐relatives. Heritability estimates provide one measure of phenotypic resemblance but are not easily incorporated into analyses of archaeological samples. In this study we evaluate the assumption that relatives are more similar phenotypically than non‐relatives. We compare results for permanent dental morphology to those obtained using deciduous dental morphology in a matched dataset (Paul & Stojanowski, ). Materials and Methods Permanent trait expression was scored from dental casts representing 69 sibling pairs, curated as part of the longitudinal Burlington Growth Study. Simulating a biodistance approach, 22 morphological traits of permanent tooth crowns were used to generate 69 inter‐relative and 2,076 non‐relative Euclidean distances. Following distance ordination, family‐specific dispersion values were calculated from multidimensional scaling coordinates. Output was compared to that of a previous study that focused on deciduous crown variation in the same set of individuals (Paul & Stojanowski, ). Mantel tests were used to evaluate the correlation of a proxy genetic distance matrix to both the permanent and deciduous dental distance matrices. Results On average, inter‐relative distances generated from morphological traits of permanent tooth crowns were smaller than expected by chance based on resampling (p < 0.001). While family‐specific dispersion varied greatly for both permanent and deciduous datasets, over 75% of the families exhibited greater dispersion with permanent traits. This suggests that morphological traits of the permanent dentition provide a less faithful reflection of biological relatedness than morphological traits of the deciduous dentition. Mantel tests indicate that both the deciduous and permanent distance matrices are significantly correlated with a matrix of genetic relatedness coefficients; however, the magnitude of the correlations was low. Discussion Overall, morphological traits of permanent tooth crowns perform moderately well in distinguishing relatives from non‐relatives, but deciduous crown variations may provide a more direct reflection of the underlying genetic structure of intra‐site or intra‐cemetery samples. These findings have implications for bioarchaeological research and biodistance practices. In particular, morphological traits of the deciduous dentition should be incorporated into standard data collection protocols because of their stronger signal of relatedness.

  June 19, 2017   doi: 10.1002/ajpa.23260   open full text
• Raw material procurement for termite fishing tools by wild chimpanzees in the Issa valley, Western Tanzania.
  Katarina Almeida‐Warren, Volker Sommer, Alex K. Piel, Alejandra Pascual‐Garrido.
  American Journal of Physical Anthropology. June 16, 2017
  Objectives Chimpanzee termite fishing has been studied for decades, yet the selective processes preceding the manufacture of fishing tools remain largely unexplored. We investigate raw material selection and potential evidence of forward planning in the chimpanzees of Issa valley, western Tanzania. Materials and Methods Using traditional archaeological methods, we surveyed the location of plants from where chimpanzees sourced raw material to manufacture termite fishing tools, relative to targeted mounds. We measured raw material abundance to test for availability and selection. Statistics included Chi‐Squared, two‐tailed Wilcoxon, and Kruskall–Wallace tests. Results Issa chimpanzees manufactured extraction tools only from bark, despite availability of other suitable materials (e.g., twigs), and selected particular plant species as raw material sources, which they often also exploit for food. Most plants were sourced 1–16 m away from the mound, with a maximum of 33 m. The line of sight from the targeted mound was obscured for a quarter of these plants. Discussion The exclusive use of bark tools despite availability of other suitable materials indicates a possible cultural preference. The fact that Issa chimpanzees select specific plant species and travel some distance to source them suggests some degree of selectivity and, potentially, forward planning. Our results have implications for the reconstruction of early hominin behaviors, particularly with regard to the use of perishable tools, which remain archaeologically invisible.

  June 16, 2017   doi: 10.1002/ajpa.23269   open full text
• Maize (Zea mays) consumption in the southern andes (30°–31° S. Lat): Stable isotope evidence (2000 BCE–1540 CE).
  Marta Alfonso‐Durruty, Andrés Troncoso, Pablo Larach, Cristian Becker, Nicole Misarti.
  American Journal of Physical Anthropology. June 16, 2017
  Objectives The timing and dietary role of maize agriculture is central to archaeological discussions in the Andean region. In the semi‐arid region of northern Chile (SARNC), archaeological models propose that maize was adopted during the Early Ceramic period in tandem with pottery and sedentism. Through stable isotope (SI) analyses, of bone collagen and apatite, this study assesses the timing of maize introduction, diachronic changes (2,000 BCE to 1,540 CE.), and synchronic dietary variability in the prehistoric SARNC. Materials and Methods Fifty‐two prehistoric individuals from SARNC were analyzed for δ13Cap, δ13Ccol, and δ15N. Descriptive statistics were used to characterize the results by period and location (inland and coast). Between‐periods (ANOVA or Kruskal‐Wallis tests), and synchronic comparisons (inland vs. coast; Student's t‐tests), were conducted. A SIAR model was run to further evaluate dietary changes. Dietary interpretations are based on food web data. Results Coastal groups show significant changes in the diet during the Middle (900‐1,000CE; enrichment in δ13C), and Late Intermediate periods (100‐1450CE; when the Δ13Cap‐col is above 5.2‰). In the inland, significant changes in SI occurred in the Late Intermediate period (δ13C enrichment). In the Late period, the inland diet became enriched for δ15N. Synchronic comparisons showed coastal individuals to have higher δ15N. Discussion The popularization of maize in the SARNC was not associated with the appearance of pottery and/or sedentism, and its role as a dietary staple was a late phenomenon (c.a. 1,000CE). The results obtained in this study show that the adoption and consumption of maize varied dramatically in the Southern Andes.

  June 16, 2017   doi: 10.1002/ajpa.23263   open full text
• The sex‐selective impact of the Black Death and recurring plagues in the Southern Netherlands, 1349–1450.
  Daniel R. Curtis, Joris Roosen.
  American Journal of Physical Anthropology. June 15, 2017
  Although recent work has begun to establish that early modern plagues had selective mortality effects, it was generally accepted that the initial outbreak of Black Death in 1347‐52 was a “universal killer.” Recent bioarchaeological work, however, has argued that the Black Death was also selective with regard to age and pre‐plague health status. The issue of the Black Death's potential sex selectivity is less clear. Bioarchaeological research hypothesizes that sex‐selection in mortality was possible during the initial Black Death outbreak, and we present evidence from historical sources to test this notion. Objective To determine whether the Black Death and recurring plagues in the period 1349–1450 had a sex‐selective mortality effect. Materials and Methods We present a newly compiled database of mortality information taken from mortmain records in Hainaut, Belgium, in the period 1349–1450, which not only is an important new source of information on medieval mortality, but also allows for sex‐disaggregation. Results We find that the Black Death period of 1349–51, as well as recurring plagues in the 100 years up to 1450, often had a sex‐selective effect—killing more women than in “non‐plague years.” Discussion Although much research tends to suggest that men are more susceptible to a variety of diseases caused by bacteria, viruses and parasites, we cannot assume that the same direction of sex‐selection in mortality applied to diseases in the distant past such as Second Pandemic plagues. While the exact reasons for the sex‐selective effect of late‐medieval plague are unclear in the absence of further data, we suggest that simple inequities between the sexes in exposure to the disease may not have been a key driver.

  June 15, 2017   doi: 10.1002/ajpa.23266   open full text
• Carbon, nitrogen and oxygen isotope fractionation during food cooking: Implications for the interpretation of the fossil human record.
  Aurélien Royer, Valérie Daux, François Fourel, Christophe Lécuyer.
  American Journal of Physical Anthropology. June 12, 2017
  Objectives Stable isotope data provide insight into the reconstruction of ancient human diet. However, cooking may alter the original stable isotope compositions of food due to losses and modifications of biochemical and water components. Methods To address this issue, carbon, nitrogen and oxygen isotope ratios were measured on meat aliquots sampled from various animals such as pork, beef, duck and chicken, and also from the flesh of fishes such as salmon, European seabass, European pilchard, sole, gilt‐head bream, and tuna. For each specimen, three pieces were cooked according to the three most commonly‐known cooking practices: boiling, frying and roasting on a barbecue. Results Our data show that cooking produced isotopic shifts up to 1.8‰, 3.5‰, and 5.2‰ for δ13C, δ15N, and δ18O values, respectively. Such variations between raw and cooked food are much greater than previously estimated in the literature; they are more sensitive to the type of food rather than to the cooking process itself, except in the case of boiling. Conclusions Reconstructions of paleodietary may thus suffer slight bias in cases of populations with undiversified diets that are restrained toward a specific raw or cooked product, or using a specific cooking mode. In cases of oxygen isotope compositions from skeletal remains (bones, teeth), they not only constitute a valuable proxy for reconstructing past climatic conditions, but they could also be used to improve our knowledge of past human diet.

  June 12, 2017   doi: 10.1002/ajpa.23246   open full text
• Chimpanzee ankle and foot joint kinematics: Arboreal versus terrestrial locomotion.
  Nicholas B. Holowka, Matthew C. O'Neill, Nathan E. Thompson, Brigitte Demes.
  American Journal of Physical Anthropology. June 08, 2017
  Objectives Many aspects of chimpanzee ankle and midfoot joint morphology are believed to reflect adaptations for arboreal locomotion. However, terrestrial travel also constitutes a significant component of chimpanzee locomotion, complicating functional interpretations of chimpanzee and fossil hominin foot morphology. Here we tested hypotheses of foot motion and, in keeping with general assumptions, we predicted that chimpanzees would use greater ankle and midfoot joint ranges of motion during travel on arboreal supports than on the ground. Methods We used a high‐speed motion capture system to measure three‐dimensional kinematics of the ankle and midfoot joints in two male chimpanzees during three locomotor modes: terrestrial quadrupedalism on a flat runway, arboreal quadrupedalism on a horizontally oriented tree trunk, and climbing on a vertically oriented tree trunk. Results Chimpanzees used relatively high ankle joint dorsiflexion angles during all three locomotor modes, although dorsiflexion was greatest in arboreal modes. They used higher subtalar joint coronal plane ranges of motion during terrestrial and arboreal quadrupedalism than during climbing, due in part to their use of high eversion angles in the former. Finally, they used high midfoot inversion angles during arboreal locomotor modes, but used similar midfoot sagittal plane kinematics across all locomotor modes. Discussion The results indicate that chimpanzees use large ranges of motion at their various ankle and midfoot joints during both terrestrial and arboreal locomotion. Therefore, we argue that chimpanzee foot anatomy enables a versatile locomotor repertoire, and urge caution when using foot joint morphology to reconstruct arboreal behavior in fossil hominins.

  June 08, 2017   doi: 10.1002/ajpa.23262   open full text
• New evidence suggesting a dissociated etiology for cribra orbitalia and porotic hyperostosis.
  Frances Rivera, Marta Mirazón Lahr.
  American Journal of Physical Anthropology. June 08, 2017
  Objectives Porotic hyperostosis (PH), characterized by porotic lesions on the cranial vault, and cribra orbitalia (CO), a localized appearance of porotic lesions on the roof of the orbits, are relatively common osteological conditions. Their etiology has been the focus of several studies, and an association with anemia has long been suggested. Anemia often causes bone marrow hypertrophy or hyperplasia, leading to the expansion in trabecular or cranial diploic bone as a result of increased hematopoiesis. Hypertrophy and/or hyperplasia is often coupled with a disruption of the remodeling process of outer cortical bone, cranially and/or postcranially, leading to the externally visible porotic lesions reported in osteological remains. In this article, we investigate whether individuals with CO have increased thickness of the diploë, the common morphological direct effect of increased hematopoiesis, and thus test the relationship between the two conditions, as well as explore the type of anemia that underlie it. Methods An analysis of medical CT scans of a worldwide sample of 98 complete, young to middle‐aged adult dry skulls from the Duckworth Collection was conducted on male and female cribrotic individuals (n = 23) and noncribrotic individuals (n = 75), all of whom lacked any evidence of porotic lesions on the vault. Measurements of total and partial cranial thickness were obtained by virtual landmark placement, using the Amira 5.4 software; all analyses were conducted in IBM SPSS 21. Results Cribriotic individuals have significantly thinner diploic bone and thicker outer and inner tables than noncribriotic individuals, contrary to the expected diploic expansion that would result from anemic conditions associated to bone marrow hypertrophy or hyperplasia. Additionally, individuals without CO and those with the condition have distinctive cranial thickness at particular locations across the skull and the severity to which CO is expressed also differentiates between those with mild and those with a moderate to severe form of the condition. Conclusions Our results suggest a complex pattern of causality in relation to the pathologies that may lead to the formation of porotic lesions on the vault and the roof of the orbits. A form of anemia may be behind the osteological changes observed in PH and CO, but it is unlikely to be the same type of anemic condition that underlies both types of osteological lesions. We suggest that CO may be associated to anemias that lead to diploic bone hypocellularity and hypoplasia, such as those caused by anemia of chronic disease and, to a lesser extent, of renal failure, aplastic anemia, protein deficiency, and anemia of endocrine disorders, and not those that lead to bone marrow hypercellularity and hyperplasia and potential PH. This leads us to the conclusion that the terms PH and CO should be used to reflect different underlying conditions.

  June 08, 2017   doi: 10.1002/ajpa.23258   open full text
• Dental evidence for wild tuber processing among Titicaca Basin foragers 7000 ybp.
  James T. Watson, Randall Haas.
  American Journal of Physical Anthropology. June 05, 2017
  Objectives The objective of this work is to characterize dental wear in a skeletal sample dating to the Middle/Late Archaic period transition (8,000‐6,700 cal. B.P.) from the Lake Titicaca Basin, Peru to better define subsistence behaviors of foragers prior to incipient sedentism and food production. Materials and Methods The dental sample consists of 251 teeth from 11 individuals recovered from the site of Soro Mik'aya Patjxa (SMP), the earliest securely dated burial assemblage in the Lake Titicaca Basin and the only burial assemblage in the region from an unequivocal forager context. Occlusal surface wear was quantified according to Smith (1984) and Scott (1979a) to characterize diversity within the site and to facilitate comparison with other foraging groups worldwide. General linear modeling was used to assess observation error and principal axis analysis was used to compare molar wear rates and angles. Teeth were also examined for caries and specialized wear. Results Occlusal surface attrition is generally heavy across the dental arcade and tends to be flat among posterior teeth. Only one carious lesion was observed. Five of the 11 individuals exhibit lingual surface attrition of the maxillary anterior teeth (LSAMAT). Discussion Tooth wear rates, molar wear plane, and caries rates are consistent with terrestrial foraging and a diverse diet. The presence of LSAMAT indicates tuber processing. The results therefore contribute critical new data toward our understanding of forager diet in the Altiplano prior to plant and animal domestication in the south‐central Andes.

  June 05, 2017   doi: 10.1002/ajpa.23261   open full text
• A multi‐method assessment of bone maintenance and loss in an Imperial Roman population: Implications for future studies of age‐related bone loss in the past.
  Patrick Beauchesne, Sabrina C. Agarwal.
  American Journal of Physical Anthropology. June 05, 2017
  Objectives One of the hallmarks of contemporary osteoporosis and bone loss is dramatically higher prevalence of loss and fragility in females post‐menopause. In contrast, bioarchaeological studies of bone loss have found a greater diversity of age‐ and sex‐related patterns of bone loss in past populations. We argue that the differing findings may relate to the fact that most studies use only a single methodology to quantify bone loss and do not account for the heterogeneity and complexity of bone maintenance across the skeleton and over the life course. Methods We test the hypothesis that bone mass and maintenance in trabecular bone sites versus cortical bone sites will show differing patterns of age‐related bone loss, with cortical bone sites showing sex difference in bone loss that are similar to contemporary Western populations, and trabecular bone loss at earlier ages. We investigated this hypothesis in the Imperial Roman population of Velia using three methods: radiogrammetry of the second metacarpal (N = 71), bone histology of ribs (N = 70), and computerized tomography of trabecular bone architecture (N = 47). All three methods were used to explore sex and age differences in patterns of bone loss. Results The suite of methods utilized reveal differences in the timing of bone loss with age, but all methods found no statistically significant differences in age‐related bone loss. Discussion We argue that a multi‐method approach reduces the influence of confounding factors by building a reconstruction of bone turnover over the life cycle that a limited single‐method project cannot provide. The implications of using multiple methods beyond studies of bone loss are also discussed.

  June 05, 2017   doi: 10.1002/ajpa.23256   open full text
• Error in geometric morphometric data collection: Combining data from multiple sources.
  Chris Robinson, Claire E. Terhune.
  American Journal of Physical Anthropology. June 02, 2017
  Objectives This study compares two‐ and three‐dimensional morphometric data to determine the extent to which intra‐ and interobserver and intermethod error influence the outcomes of statistical analyses. Materials and Methods Data were collected five times for each method and observer on 14 anthropoid crania using calipers, a MicroScribe, and 3D models created from NextEngine and microCT scans. ANOVA models were used to examine variance in the linear data at the level of genus, species, specimen, observer, method, and trial. Three‐dimensional data were analyzed using geometric morphometric methods; principal components analysis was employed to examine how trials of all specimens were distributed in morphospace and Procrustes distances among trials were calculated and used to generate UPGMA trees to explore whether all trials of the same individual grouped together regardless of observer or method. Results Most variance in the linear data was at the genus level, with greater variance at the observer than method levels. In the 3D data, interobserver and intermethod error were similar to intraspecific distances among Callicebus cupreus individuals, with interobserver error being higher than intermethod error. Generally, taxa separate well in morphospace, with different trials of the same specimen typically grouping together. However, trials of individuals in the same species overlapped substantially with one another. Conclusion Researchers should be cautious when compiling data from multiple methods and/or observers, especially if analyses are focused on intraspecific variation or closely related species, as in these cases, patterns among individuals may be obscured by interobserver and intermethod error. Conducting interobserver and intermethod reliability assessments prior to the collection of data is recommended.

  June 02, 2017   doi: 10.1002/ajpa.23257   open full text
• Using urinary parameters to estimate seasonal variation in the physical condition of female white‐faced capuchin monkeys (Cebus capucinus imitator).
  Mackenzie L. Bergstrom, Melissa Emery Thompson, Amanda D. Melin, Linda M. Fedigan.
  American Journal of Physical Anthropology. May 27, 2017
  Objectives The physical condition of females depends on access to resources, which vary over space and time. Assessing variation in physical condition can help identify factors affecting reproductive success, but noninvasive measurement is difficult in wild animals. Creatinine concentration relative to the specific gravity (i.e., density) of urine has promise for noninvasively quantifying the relative muscle mass (RMM) of wild primates. We verified the relationship between these urinary parameters for wild white‐faced capuchin monkeys, and assessed temporal changes in the RMM of females across groups and between periods of high and low resource abundance. Materials and Methods We collected urine from 25 adult females in three groups across varying seasons at Sector Santa Rosa, Costa Rica. We measured the specific gravity and creatinine concentration of 692 samples and the effect of specific gravity on creatinine concentration. We used the residuals of this relationship to measure effects of group and season using mixed‐effects models. Results Specific gravity significantly predicted creatinine concentration. Season, group membership and the interaction between these variables were significant predictors of residual creatinine variation. Specifically, RMM was higher during months with high fruit energy density, lower in one social group, and less variable among females in the smallest group. Discussion Our findings suggest that specific gravity and creatinine may be used as urinary parameters to make inferences about the RMM of capuchins. Using this technique, we infer that females experienced changes in muscle mass according to variation in resource energy availability and social group variation.

  May 27, 2017   doi: 10.1002/ajpa.23239   open full text
• Temporal trends in craniometric estimates of admixture for a modern American sample.
  Bridget F. B. Algee‐Hewitt.
  American Journal of Physical Anthropology. May 24, 2017
  Objectives Temporal trends in craniometric estimates of admixture are investigated for three U.S. populations in the FDB. Patterns of association between birth years and posterior probabilities of cluster membership are identified to assess how these proportions of admixture have changed over recent time. Demographic and genetic data correlates, patterns of morphological expression, and shifts in source populations are evaluated. Materials and Methods Estimates of three‐way admixture were obtained for 1,521 individuals of documented population, sex, and birth years that span the 20th century. Correlations were calculated between birth years and admixture proportions for members of each FDB population. Population and sex‐specific admixture variation was further assessed by ANOVA and regression. Correlation analysis was used to identify, per population, which of the cranial measurements change in dimension under increased or decreased admixture. Results Admixture proportions differ significantly by population and change over time. No sex differences are detected. Analysis of the relationship between admixture proportions and ILDs finds that admixture drives morphological change in areas of the cranium known to vary among populations. Results agree with prior work on secular change. Discussion Findings reveal a progressive increase in White‐European population admixture for the self‐identified Black individuals, a recent demographic shift toward the increased representation of Hispanic individuals carrying greater Native American ancestry, and reduction in admixture for White individuals that suggest a loss of diversity over time. Changes in admixture produce tractable differences in morphological expression. Both sexes exhibit similar admixture proportions and self‐identification patterns. Observed diachronic trends are corroborated by information on recent U.S. demographic change.

  May 24, 2017   doi: 10.1002/ajpa.23242   open full text
• Age estimation of immature human skeletal remains from the dimensions of the girdle bones in the postnatal period.
  Hugo F. V. Cardoso, Laure Spake, Louise T. Humphrey.
  American Journal of Physical Anthropology. May 24, 2017
  Objectives This study provides classical calibration regression formulae for age estimation from the dimensions of unfused shoulder and pelvic girdle bones. Materials and methods Age estimation models were derived from a sample of 160 known age and sex individuals (63 females and 97 males) aged birth to 12 years, selected from Portuguese and English skeletal collections. The sample was divided into two age groups at the age of 2 years, and formulae were obtained for the sexes separately and combined. Results Measurements of the pelvis provide more precise age estimates than the shoulder. In the younger age group, the height and width of the ilium, and the height of the glenoid yield the most precise age estimates. In the older age group, the length of the clavicle provides the most precise estimates, followed by measurements of the pubis and ischium. Discussion In the younger individuals (<2 years), age estimates based on measurements of the pelvic girdle seem to be as or more precise than those based on the length of long bones. In older individuals (≥2 years), estimates based on the measurements of the girdles are less precise than those based on the length of long bones. These age estimation formulae may be useful for fragmentary and incomplete material in archaeological and forensic contexts. The formulae are suitable for a variety of archeological populations living under adverse conditions. These conditions are similar to some “developing” countries, and hence the formulae may also be applicable to modern forensic remains from such environments.

  May 24, 2017   doi: 10.1002/ajpa.23248   open full text
• Occupational manual activity is reflected on the patterns among hand entheses.
  Fotios Alexandros Karakostis, Gerhard Hotz, Heike Scherf, Joachim Wahl, Katerina Harvati.
  American Journal of Physical Anthropology. May 24, 2017
  Objectives In anthropological sciences, entheses are widely utilized as occupational stress markers. However, the reaction of entheseal surfaces to mechanical loading is not well understood. Furthermore, previous studies on entheses relied on the individuals' occupation‐at‐death. Past research by one of us has identified two patterns among hand entheses, proposing that they reflect two synergistic muscle groups. Here, we investigate the association between these patterns and habitual manual activity using an extensively documented skeletal sample and a three‐dimensional system of quantification. Materials and Methods The hand bones utilized belong to 45 individuals from mid‐19th century Basel. These were male adults (18 to 48 years old) who were not directly related, showed no manual pathological conditions, and whose occupational activities during their lifetime were clearly documented and could be evaluated according to historical sources. The patterns of entheses were explored using principal component analysis on both raw and size‐adjusted variables. The influence of age‐at‐death, body mass, and bone length was assessed through correlation tests. Results The analysis showed that the previously proposed patterns of entheses are present in our sample. Individuals with the same or comparable occupations presented similar entheseal patterns. These results were not considerably affected by entheseal overall size, age‐at‐death, body mass, or bone length. Discussion Individuals involved in intense manual labor during their lifetime presented a distinctive pattern of hand entheses, consistent with the application of high grip force. By contrast, individuals with less strenuous and/or highly mechanized occupations showed an entheseal pattern related to the thumb intrinsic muscles.

  May 24, 2017   doi: 10.1002/ajpa.23253   open full text
• Application of geographic information systems to investigating associations between social status and burial location in medieval Trino Vercellese (Piedmont, Italy).
  Marissa C. Stewart, Giuseppe Vercellotti.
  American Journal of Physical Anthropology. May 24, 2017
  Objectives Socioeconomic status differences in skeletal populations are often inferred from skeletal indicators of stress and burial location. However, to date, the association between osteometric parameters and spatial location in relation to socioeconomic status in medieval Italy has not been explicitly tested. Materials and Methods This study examined the spatial distribution of osteometric data in the medieval (8th–13th c.) cemetery of San Michele di Trino (Trino Vercellese, VC, Italy) to determine whether skeletal correlates of socioeconomic status correspond with privileged burial locations. Specifically, we tested the hypothesis that greater growth outcomes are associated with privileged burials located inside the church by examining osteometric data (femoral bicondylar length [N = 74], maximum tibial length [N = 62], and the sum of the two measurements [N = 59]) in a geographic information system (GIS) of the cemetery. Results Getis‐Ord G Hot Spot analysis identified significant (90% CI) spatial clustering of high osteometric values within the church, while low values clustered in areas of the cemetery farther from the church. These results, supported by the results of interpolation analyses, became more pronounced when z‐scores were calculated to combine the male and female samples and the analyses were repeated. Discussion Overall, the findings corroborate the observation that the spatial distribution of osteometric data reflects socioeconomic status differences within the population. This research exemplifies the advantages of integrating bioarchaeology and spatial analysis to examine mortuary behavior and health outcomes in highly stratified societies where access to resources is demarcated in both life and in death.

  May 24, 2017   doi: 10.1002/ajpa.23251   open full text
• Trabecular and cortical bone structure of the talus and distal tibia in Pan and Homo.
  Zewdi J. Tsegai, Matthew M. Skinner, Andrew H. Gee, Dieter H. Pahr, Graham M. Treece, Jean‐Jacques Hublin, Tracy L. Kivell.
  American Journal of Physical Anthropology. May 24, 2017
  Objectives Internal bone structure, both cortical and trabecular bone, remodels in response to loading and may provide important information regarding behavior. The foot is well suited to analysis of internal bone structure because it experiences the initial substrate reaction forces, due to its proximity to the substrate. Moreover, as humans and apes differ in loading of the foot, this region is relevant to questions concerning arboreal locomotion and bipedality in the hominoid fossil record. Materials and methods We apply a whole‐bone/epiphysis approach to analyze trabecular and cortical bone in the distal tibia and talus of Pan troglodytes and Homo sapiens. We quantify bone volume fraction (BV/TV), degree of anisotropy (DA), trabecular thickness (Tb.Th), bone surface to volume ratio (BS/BV), and cortical thickness and investigate the distribution of BV/TV and cortical thickness throughout the bone/epiphysis. Results We find that Pan has a greater BV/TV, a lower BS/BV and thicker cortices than Homo in both the talus and distal tibia. The trabecular structure of the talus is more divergent than the tibia, having thicker, less uniformly aligned trabeculae in Pan compared to Homo. Differences in dorsiflexion at the talocrural joint and in degree of mobility at the talonavicular joint are reflected in the distribution of cortical and trabecular bone. Discussion Overall, quantified trabecular parameters represent overall differences in bone strength between the two species, however, DA may be directly related to joint loading. Cortical and trabecular bone distributions correlate with habitual joint positions adopted by each species, and thus have potential for interpreting joint position in fossil hominoids.

  May 24, 2017   doi: 10.1002/ajpa.23249   open full text
• Investigating biogeographic boundaries of the Sunda shelf: A phylogenetic analysis of two island populations of Macaca fascicularis.
  A.R. Klegarth, S.A. Sanders, A.D. Gloss, K.E. Lane‐deGraaf, L. Jones‐Engel, A. Fuentes, H. Hollocher.
  American Journal of Physical Anthropology. May 13, 2017
  Objectives Cyclical submergence and re‐emergence of the Sunda Shelf throughout the Pleistocene served as a dynamic biogeographic landscape, across which long‐tailed macaques (Macaca fascicularis) have migrated and evolved. Here, we tested the integrity of the previously reported continental‐insular haplotype divide reported among Y and mitochondrial DNA lineages across multiple studies. Materials and Methods The continental‐insular haplotype divide was tested by heavily sampling wild macaques from two important biogeographic regions within Sundaland: (1) Singapore, the southernmost tip of continental Asia and (2) Bali, Indonesia, the southeastern edge of the Indonesian archipelago, immediately west of Wallace's line. Y DNA was haplotyped for samples from Bali, deep within the Indonesian archipelago. Mitochondrial D‐loop from both islands was analyzed against existing data using Maximum Likelihood and Bayesian approaches. Results We uncovered both “continental” and “insular” Y DNA haplotypes in Bali. Between Singapore and Bali we found 52 unique mitochondrial haplotypes, none of which had been previously described. Phylogenetic analyses confirmed a major haplogroup division within Singapore and identified five new Singapore subclades and two primary subclades in Bali. Discussion While we confirmed the continental‐insular divide among mtDNA haplotypes, maintenance of both Y DNA haplotypes on Bali, deep within the Indonesian archipelago calls into question the mechanism by which Y DNA diversity has been maintained. It also suggests the continental‐insular designation is less appropriate for Y DNA, leading us to propose geographically neutral Y haplotype designations.

  May 13, 2017   doi: 10.1002/ajpa.23235   open full text
• Deviant burials and social identity in a postmedieval polish cemetery: An analysis of stable oxygen and carbon isotopes from the “vampires” of Drawsko.
  Lesley A. Gregoricka, Amy B. Scott, Tracy K. Betsinger, Marek Polcyn.
  American Journal of Physical Anthropology. May 12, 2017
  Objectives Deviant burials can reveal important information about both social and individual identity, particularly when the mortuary record is supplemented by an examination of skeletal remains. At the postmedieval (17th to 18th c. AD) cemetery of Drawsko (Site 1), Poland, six individuals (of n = 285) received deviant, anti‐vampiristic mortuary treatment. A previous study using radiogenic strontium isotope ratios ( x¯= 0.7112 ± 0.0006, 1σ, n = 60) found that these “vampires” were in fact locals, not migrants to the region targeted for deviant burial due to their status as immigrant outsiders. However, considerable geologic overlap in strontium isotope ratios across the North European Plain may have masked the identification of at least some nonlocal individuals. This study further contextualizes strontium isotope ratios using additional biogeochemical data to test the hypothesis that additional nonlocals were present in the Drawsko cemetery. Methods Stable oxygen and carbon isotopes from the dental enamel of 58 individuals interred in both normative and atypical burials at Drawsko were analyzed. Results Both δ18Oc(VPDB) ( x¯= −4.5 ± 0.7‰) and δ13Cap isotope values ( x¯= −13.6 ± 0.8‰) displayed little variability and were not significantly different between vampire and normative burials, supporting prior strontium results of a largely local population. Nevertheless, homogeneity in oxygen isotope values across other northern European sites makes it difficult to speculate about isotopic regional diversity, leaving open the possibility that additional migrants to the region remain undetected. Additionally, carbon isotope values point to a locally sourced diet dominated by C3 resources but with some supplementation by C4 goods that likely included millet, fitting with historic descriptions of postmedieval diet in Poland. Conclusions Those interred as vampires appear local to the region and thus likely underwent deviant funerary treatment due to some other social stigma not apparent from the skeleton.

  May 12, 2017   doi: 10.1002/ajpa.23244   open full text
• Differential investment in body girths by sex: Evidence from 3D photonic scanning in a Thai cohort.
  Meghan K. Shirley, Tim J. Cole, Supiya Charoensiriwath, Philip Treleaven, Jonathan C.K. Wells.
  American Journal of Physical Anthropology. May 12, 2017
  Objectives Life history trade‐offs may manifest between competing organs and tissues in the body. Sexual dimorphism in tissue investment is well‐established in humans, with sex‐associated body shape differences linked to natural and sexual selection. This study uses three‐dimensional (3D) photonic scanning to test whether males and females differentially invest energy in various body regions in relation to two independent proxies of growth. Materials and methods Body shape data (multiple girths) came from a Thai cohort (n = 11,610; 53% female; age range 21‐88 years). Weight was considered a proxy for recent energy acquisition. Stature represented completed growth, a proxy for energy acquisition earlier in life. The data were analyzed using growth‐proxy by sex interaction log‐log regression models adjusting for age, salary and number of children. Results For a given percentage increase in weight, females showed greater percentage increases than males in girths of the arm, chest, hip, thigh, knee and calf (p < 0.001), whilst males exceeded females in head and waist girths (also p < 0.001). For a given percentage increase in height, weight and all girths showed greater proportional changes in males than females (p < 0.001). Discussion These results indicate sex‐specific life history strategies wherein the direction and timing of energy investment in girths varies between the sexes. The results add to literature suggesting that sexual dimorphism in body morphology is not a fixed trait; rather, differential energy allocation to specific body regions appears to be a plastic strategy adjusted in relation to energy acquisition across the life course.

  May 12, 2017   doi: 10.1002/ajpa.23238   open full text
• The ecology of white‐handed and pileated gibbons in a zone of overlap and hybridization in Thailand.
  Norberto Asensio, Juan Manuel José‐Domínguez, Chalita Kongrit, Warren Y. Brockelman.
  American Journal of Physical Anthropology. May 08, 2017
  Objectives The study of related species in contact zones can elucidate what factors mediate species coexistence and geographical distributions. We investigated niche overlap and group interactions of two gibbon species and their hybrids co‐occurring in a zone of overlap and hybridization. Methods The location, composition and behavior of white‐handed, pileated, and mixed‐species gibbon groups were studied by following them during 31 consecutive months in a relatively large part of the contact zone. Results Twenty groups of white‐handed gibbon were mapped followed by nine groups of pileated gibbons and five mixed‐species groups. White‐handed, pileated and mixed‐species groups had similar sizes and composition, ate a high proportion of fruits, shared a large number of species in their diets, and presented similar habitat preferences. Group home range sizes did not differ between species and overlapped little with neighboring groups irrespective of species, and intraspecific and interspecific encounter rates were similar. Discussion Ecological similarities support that competition between the gibbon species exists and takes the form of interspecific territoriality. However, we could not find any clear mechanism of niche partitioning favoring coexistence between species. Our findings suggest that the contact zone is unstable and is maintained by dispersal inward from groups of the parental species. The relatively low numbers of mixed‐species groups and hybrids found suggests a high degree of premating reproductive isolation, perhaps mediated by interspecific miscommunication. The existence of hybrids and backcrosses potentially undetectable from phenotypic characters alone raises the possibility of more widespread introgression than has been evident. Hence, while interspecific territoriality should reduce the rate of gene transfer, it would not necessarily present a barrier to introgression into contiguous populations of the opposite species.

  May 08, 2017   doi: 10.1002/ajpa.23241   open full text
• Differences between biological and chronological age‐at‐death in human skeletal remains: A change of perspective.
  Lourdes R. Couoh.
  American Journal of Physical Anthropology. May 03, 2017
  Objectives This analysis seeks to determine whether differences between real and estimated chronological age (CA) with biological age (BA) in skeletal individuals reflect variability in aging. Material and methods A total of 87 individuals of two samples, ranging from 20 to 94 years old, were analyzed. One, partially documented, belongs to a Mexican skeletal collection dating to the 20th century; the other is an assemblage of prehispanic individuals from different archaeological sites. In all specimens, the tooth annulation method (TCA) was applied to estimate CA, while—excluding individuals older than 80 years—auricular surface (AS) and pubic symphysis (PS) methods were used to estimate BA. Statistical analyses were conducted to identify correlations and significance of the differences between CA vs. TCA, CA vs. AS/PS, TCA vs. AS/PS. Sex of individuals was assessed for its influence in aging. Results The use of TCA to estimate CA was successful for most individuals. A strong correlation was found between CA vs. TCA, CA vs. AS/PS, TCA vs. AS/PS and their differences were significant but variation in these were found when assessed by separate age groups. Sex did not influence such differences. Discussion TCA can be used to estimate CA and its differences with BA, being less than 10 years, are similar to those found in living populations. Differences between CA and BA are due to intra‐population variability, which could be the consequence of individual differences in aging. More research is needed to have confidence that under‐ and overestimations of BA are indicators of aging variability at the level of the individual.

  May 03, 2017   doi: 10.1002/ajpa.23236   open full text
• A tale of agriculturalists and hunter‐gatherers: Exploring the thrifty genotype hypothesis in native South Americans.
  Guillermo Reales, Diego L. Rovaris, Vanessa C. Jacovas, Tábita Hünemeier, José R. Sandoval, Alcibiades Salazar‐Granara, Darío A. Demarchi, Eduardo Tarazona‐Santos, Aline B. Felkl, Michele A. Serafini, Francisco M. Salzano, Rafael Bisso‐Machado, David Comas, Vanessa R. Paixão‐Côrtes, Maria Cátira Bortolini.
  American Journal of Physical Anthropology. May 02, 2017
  Objectives To determine genetic differences between agriculturalist and hunter‐gatherer southern Native American populations for selected metabolism‐related markers and to test whether Neel's thrifty genotype hypothesis (TGH) could explain the genetic patterns observed in these populations. Materials and Methods 375 Native South American individuals from 17 populations were genotyped using six markers (APOE rs429358 and rs7412; APOA2 rs5082; CD36 rs3211883; TCF7L2 rs11196205; and IGF2BP2 rs11705701). Additionally, APOE genotypes from 39 individuals were obtained from the literature. AMOVA, main effects, and gene‐gene interaction tests were performed. Results We observed differences in allele distribution patterns between agriculturalists and hunter‐gatherers for some markers. For instance, between‐groups component of genetic variance (FCT) for APOE rs429358 showed strong differences in allelic distributions between hunter‐gatherers and agriculturalists (p = 0.00196). Gene‐gene interaction analysis indicated that the APOE E4/CD36 TT and APOE E4/IGF2BP2 A carrier combinations occur at a higher frequency in hunter‐gatherers, but this combination is not replicated in archaic (Neanderthal and Denisovan) and ancient (Anzick, Saqqaq, Ust‐Ishim, Mal'ta) hunter‐gatherer individuals. Discussion A complex scenario explains the observed frequencies of the tested markers in hunter‐gatherers. Different factors, such as pleotropic alleles, rainforest selective pressures, and population dynamics, may be collectively shaping the observed genetic patterns. We conclude that although TGH seems a plausible hypothesis to explain part of the data, other factors may be important in our tested populations.

  May 02, 2017   doi: 10.1002/ajpa.23233   open full text
• Body growth and life history in wild mountain gorillas (Gorilla beringei beringei) from Volcanoes National Park, Rwanda.
  Jordi Galbany, Didier Abavandimwe, Meagan Vakiener, Winnie Eckardt, Antoine Mudakikwa, Felix Ndagijimana, Tara S. Stoinski, Shannon C. McFarlin.
  American Journal of Physical Anthropology. May 02, 2017
  Objectives Great apes show considerable diversity in socioecology and life history, but knowledge of their physical growth in natural settings is scarce. We characterized linear body size growth in wild mountain gorillas from Volcanoes National Park, Rwanda, a population distinguished by its extreme folivory and accelerated life histories. Methods In 131 individuals (0.09–35.26 years), we used non‐invasive parallel laser photogrammetry to measure body length, back width, arm length and two head dimensions. Nonparametric LOESS regression was used to characterize cross‐sectional distance and velocity growth curves for males and females, and consider links with key life history milestones. Results Sex differences became evident between 8.5 and 10.0 years of age. Thereafter, female growth velocities declined, while males showed increased growth velocities until 10.0–14.5 years across dimensions. Body dimensions varied in growth; females and males reached 98% of maximum body length at 11.7 and 13.1 years, respectively. Females attained 95.3% of maximum body length by mean age at first birth. Neonates were 31% of maternal size, and doubled in size by mean weaning age. Males reached maximum body and arm length and back width before emigration, but experienced continued growth in head dimensions. Conclusions While comparable data are scarce, our findings provide preliminary support for the prediction that mountain gorillas reach maximum body size at earlier ages compared to more frugivorous western gorillas. Data from other wild populations are needed to better understand comparative great ape development, and investigate links between trajectories of physical, behavioral, and reproductive maturation.

  May 02, 2017   doi: 10.1002/ajpa.23232   open full text
• Trabecular mapping: Leveraging geometric morphometrics for analyses of trabecular structure.
  Adam D. Sylvester, Claire E. Terhune.
  American Journal of Physical Anthropology. April 22, 2017
  Objectives Trabecular microstructure of limb bone epiphyses has been used to elucidate the relationship between skeletal form and behavior among mammals. Such studies have often relied on the analysis of a single volume of interest (VOI). Here we present a method for evaluating variation in bone microstructure across articular surfaces by leveraging sliding semilandmarks. Methods Two samples were used to demonstrate the proposed methodology and test the hypothesis that microstructural variables are homogeneously distributed: tali from two ape genera (Pan and Pongo, n = 9) and modern human distal femora (n = 10). Sliding semilandmarks were distributed across articular surfaces and used to locate the position of multiple VOIs immediately deep to the cortical shell. Trabecular bone properties were quantified using the BoneJ plugin for ImageJ. Nonparametric MANOVA tests were used to make group comparisons and differences were explored using principal components analysis and visualized using color maps. Results Tests reveal that trabecular parameters are not distributed homogeneously and identify differences between chimpanzee and orangutan tali with regards to trabecular spacing and degree of anisotropy, with chimpanzee tali being more anisotropic and having more uniformly spaced trabeculae. Human males and females differed in the pattern of trabecular spacing with males having more uniform trabecular spacing across the joint surface. Conclusions The proposed procedure quantifies variation in trabecular bone parameters across joint surfaces and allows for meaningful statistical comparisons between groups of interest. Consequently it holds promise to help elucidate links between trabecular bone structure and animal behavior.

  April 22, 2017   doi: 10.1002/ajpa.23231   open full text
• Brief communication: An analysis of dental development in Pleistocene Homo using skeletal growth and chronological age.
  Maja Šešelj.
  American Journal of Physical Anthropology. April 22, 2017
  Objectives This study takes a new approach to interpreting dental development in Pleistocene Homo in comparison with recent modern humans. As rates of dental development and skeletal growth are correlated given age in modern humans, using age and skeletal growth in tandem yields more accurate dental development estimates. Here, I apply these models to fossil Homo to obtain more individualized predictions and interpretations of their dental development relative to recent modern humans. Materials and Methods Proportional odds logistic regression models based on three recent modern human samples (N = 181) were used to predict permanent mandibular tooth development scores in five Pleistocene subadults: Homo erectus/ergaster, Neanderthals, and anatomically modern humans (AMHs). Explanatory variables include a skeletal growth indicator (i.e., diaphyseal femoral length), and chronological age. Results AMHs Lagar Velho 1 and Qafzeh 10 share delayed incisor development, but exhibit considerable idiosyncratic variation within and across tooth types, relative to each other and to the reference samples. Neanderthals Dederiyeh 1 and Le Moustier 1 exhibit delayed incisor coupled with advanced molar development, but differences are reduced when femoral diaphysis length is considered. Dental development in KNM‐WT 15,000 Homo erectus/ergaster, while advanced for his age, almost exactly matches the predictions once femoral length is included in the models. Discussion This study provides a new interpretation of dental development in KNM‐WT 15000 as primarily reflecting his faster rates of skeletal growth. While the two AMH specimens exhibit considerable individual variation, the Neanderthals exhibit delayed incisor development early and advanced molar development later in ontogeny.

  April 22, 2017   doi: 10.1002/ajpa.23228   open full text
• Stuck in fragments: Population genetics of the Endangered collared brown lemur Eulemur collaris in the Malagasy littoral forest.
  Stefania Bertoncini, Jacopo D'Ercole, Francesca Brisighelli, Jean‐Baptiste Ramanamanjato, Cristian Capelli, Sergio Tofanelli, Giuseppe Donati.
  American Journal of Physical Anthropology. April 21, 2017
  Objectives The Endangered collared brown lemur (Eulemur collaris) is the largest primate living in the littoral forest of southeastern Madagascar, a top priority habitat for biodiversity conservation on the island. Because this lemur is a key seed‐disperser, an evaluation of the structure and connectivity of the populations surviving in the forest fragments is urgently needed to guide conservation plans. Materials and Methods Genetic variability at autosomal microsatellites and mitochondrial DNA was investigated in a total of 49 collared brown lemurs sampled by non‐invasive methods in three littoral forest fragments and in the nearby lowland humid forest. Results The overall genetic diversity of E. collaris in the southeastern coastal region of Madagascar was lower than in other populations, as well as in other lemur species. The population appears highly structured, with less variable and more inbred groups inhabiting the littoral forest fragments compared to the inland area. Major barriers to gene flow were identified isolating littoral forest fragments from each other and from the inland lowland humid forest. Discussion Medium to long‐term drift and scarce gene flow is the scenario that best explains the current genetic distribution. Habitat discontinuities such as rivers and grassland between forest fragments played a major role in structuring the population. A common history of size contraction is pointed out by several genetic estimators, indicating a possible ecological crisis triggered around 1,300 years ago. The adoption of strategies aimed at facilitating gene flow and population growth appears crucial to delay further loss of genetic diversity.

  April 21, 2017   doi: 10.1002/ajpa.23230   open full text
• Fueguian crania and the circum‐Pacific rim variation.
  D. Turbon, C. Arenas, C. M. Cuadras.
  American Journal of Physical Anthropology. April 04, 2017
  Objectives The Fueguians are descendants of the first settlers of America, a 'relict' isolated geographically for 10,000 years. We compared their cranial variation with other Americans, and samples from Asia and Australia to know whether the modern extinct Fueguians can be considered Paleoamericans or not. Materials and Methods Herein we study 176 Fuego‐Patagonian skulls, the largest cranial sample to be studied, refined and well documented, using CVA, and the D2 of Mahalanobis. The affinities between populations and sexual dimorphism were jointly studied. Results Terrestrial hunters (Selknam) have a different cranial morphology from sea canoeists (Yamana, Alakaluf) particularly with regard to cranial size and robustness. In the American context, there are extreme differences between the canoeists of Santa Cruz (California) and the Eskimos and canoeists of Fuego‐Patagonia in terms of cranial size, prognathism and development of the frontal region. Fueguian canoeists are cranially closer to the Californian ones than to their Fueguian neighbors, the Selknam. Our results favor the hypothesis of two different flows for the origin of the first populators of Tierra del Fuego. Discussion We concluded that the robusticity of some Fuegians (Selknam) might be the result of an allometric pattern of overall robusticity expression well as a result of epigenetics or differential reproduction (Larsen, 2015:264) or hypothetical endocrine changes (Bernal et al. in Am J Hum Biol 2006;18:748–765). When compared with three Australian–Melanesian series, the group comprising Amerindians, Ainu, and Eskimos clusters together as they are all extremely different from the former in terms of both cranial size and shape.

  April 04, 2017   doi: 10.1002/ajpa.23207   open full text
• Dental wear and age grading at Roonka, South Australia.
  Judith Littleton.
  American Journal of Physical Anthropology. April 04, 2017
  Objectives In many hunter‐gatherer populations, the teeth are used as a third hand or a tool. Much attention has been paid to wear and its relationship to gendered division of labor, but age is also a significant organizing factor in many societies. In this article, I analyze whether the pattern of wear at Roonka, Australia, reflects the age‐graded acquisition of tasks. Materials and Methods The remains analyzed come from Roonka and date from c6000 BP to 150 BP. In total 126 adults and juveniles were analyzed. Wear gradients were calculated for each tooth relative to wear on the first molar. Data were compared using nonparametric statistics and cluster analysis to assess the degree of patterning within the sample. Results Dental wear proceeded rapidly. There is no evidence of sex differences in the pattern of wear. Age differences do occur. While disproportionate anterior wear occurs among juveniles and young adults, by middle adulthood the pattern is less variable and involves the premolars. Old adults have a much flatter pattern of wear. Discussion The pattern of wear is consistent with ethnographic observations, which suggest a degree of latitude in the activities of juveniles and young adults. By middle age variability between individuals declines reflecting shared tasks and more intensive use of the teeth. The pattern of wear amongst old adults, however, is much flatter presumably due to changes in occlusion. While dental wear is informative about the organization of labor there is a need to take into account both patterns of activity and occlusion.

  April 04, 2017   doi: 10.1002/ajpa.23226   open full text
• Applying wet sieving fecal particle size measurement to frugivores: A case study of the eastern chimpanzee (Pan troglodytes schweinfurthii).
  Taylor E. Weary, Richard W. Wrangham, Marcus Clauss.
  American Journal of Physical Anthropology. April 04, 2017
  Objectives Fecal particle size (FPS) as quantified by wet sieving analysis is a measure of chewing efficiency relevant for the understanding of physiological adaptations and constraints in herbivores. FPS has not been investigated systematically in frugivores, and important methodological problems remain. In particular, food items that are not chewed may skew estimates of FPS. We address such methodological issues and also assess the influence of diet type and age on FPS in wild chimpanzees. Materials and Methods About 130 fecal samples of 38 individual chimpanzees (aged from 1.3 to ∼55 years) from the Kanyawara community of Kibale National Park (Uganda) were collected during three fruit seasons and analyzed using standardized wet sieves (pores from 16 to 0.025 mm). The effects of using different sieve series and excluding large seeds were investigated. We also assessed the relationship between FPS and sex, age, and fruit season. Results The treatment of seeds during the sieving process had a large influence on the results. FPS was not influenced by chimpanzee sex or age, but was smaller during a fig season (0.88 ± 0.31 mm) than during two drupe‐fruit seasons (1.68 ± 0.37 mm) (0.025–4 mm sieves, excluding seeds). Discussion The absence of an age effect on FPS suggests that dental senescence might be less critical in chimpanzees, or in frugivores in general, than in folivorous herbivores. To increase the value of FPS studies for understanding frugivore and hominoid dietary evolution we propose modifications to prior herbivore protocols.

  April 04, 2017   doi: 10.1002/ajpa.23225   open full text
• The 5th national survey on the physical growth and development of children in the nine cities of China: Anthropometric measurements of Chinese children under 7 years in 2015.
  Ya‐Qin Zhang, Hui Li, Hua‐Hong Wu, Xin‐Nan Zong, Zong‐Han Zhu, Ying Pan, Jia Li, Xing‐Rong Zheng, Mei Wei, Mei‐Ling Tong, Ai‐Fen Zhou, Yan Hu, Wei Chen, Ke Zhu, Yang Yu.
  American Journal of Physical Anthropology. April 04, 2017
  Objectives To describe the physical growth of healthy children under 7 years in China based on the latest national survey and provide more data for revising growth reference and monitoring the impact of social development on children's health and growth. Methods In the cross‐sectional survey, 161,774 healthy children under 7 years were selected by multistage stratified cluster sampling method in nine cities of China. According to the geographical location, the nine cities were divided into northern, central and southern regions, and each city included urban and suburban areas. Anthropometric measurements were obtained on the spots and other related information was collected with questionnaires. Results There were slight urban–suburban difference and obvious regional difference in anthropometric measurements in China. Comparison with the 4th NSPGDC in 2005, measurements increased 0.1–1.1 kg in weight, 0.5–1.8 cm in height in urban areas (except children under 3 years) and 0.1–2.5 kg in weight, 0.2–3.8 cm in height in suburban areas. The urban–suburban difference of those measurements became smaller than 10 years ago, but their regional difference persistently exist. Chinese children were 0.36 SD in weight, 0.43 SD in height in urban areas and 0.30 SD in weight, 0.30 SD in height in suburban areas higher than WHO standards. Conclusions Physical growth of children under 7 years old was undergoing a slowly positive secular trend during the latest decade in more economically developed regions of China. Urban–suburban difference of those measurements became smaller, while their regional difference persistently exist. Chinese healthy children under 7 years in nine cities was taller and heavier than WHO standards.

  April 04, 2017   doi: 10.1002/ajpa.23224   open full text
• Buccal dental microwear texture and catarrhine diets.
  Andrés Aliaga‐Martínez, Alejandro Romero, Jordi Galbany, R. Adriana Hernández‐Aguilar, Alejandro Pérez‐Pérez.
  American Journal of Physical Anthropology. March 28, 2017
  Objectives Two‐dimensional dental microwear analyses on occlusal and nonocclusal enamel surfaces have been widely applied to reconstruct the feeding behaviors of extant primates and to infer ecological adaptations in fossil hominins. To date, analyses of dental microwear texture, using three‐dimensional, Scale‐Sensitive Fractal Analysis approaches has only been applied to occlusal surfaces. Here, for the first time, we apply this 3D proxy to buccal enamel surfaces of catarrhine primates of known feeding ecologies to assess the utility of nonocclusal microwear texture variables as indicators of dietary habits. Materials and Methods Buccal microwear texture attributes were collected from high‐resolution second molar casts in a sample of seven extant African catarrhine taxa with differing dietary behaviors. A white‐light confocal microscope with a 100× objective lens was used to record six microwear texture variables that assess complexity, anisotropy, heterogeneity, and textural fill volume. Results The physical properties and variation in hardness of ingested foods is reflected by significant differences in the microwear variables on buccal enamel surfaces between species, which is in agreement with early reports using 2D microwear signatures of the same samples. Species that consume hard brittle items showed high buccal enamel complexity and low anisotropy values, while folivorous species that consume tough foods revealed high anisotropy and low complexity enamel patterns. Discussion Buccal microwear texture analysis on enamel surfaces clearly reflects diet‐related variation in nonhuman primates. Our findings indicate that microwear texture attributes on nonworking enamel surfaces provide an alternative procedure for reconstructing dietary behavior when wear facets on occlusal surfaces are lacking.

  March 28, 2017   doi: 10.1002/ajpa.23219   open full text
• Feeding in fear? How adult male western chimpanzees (Pan troglodytes verus) adjust to predation and savanna habitat pressures.
  Stacy Lindshield, Brent J. Danielson, Jessica M. Rothman, Jill D. Pruetz.
  American Journal of Physical Anthropology. March 28, 2017
  Objectives We evaluated risk‐sensitive foraging in adult male western chimpanzees (Pan troglodytes verus) occupying a savanna environment at Fongoli, Senegal. The aim of this study was to determine how the risks of predation and heat stress influenced their behavior while feeding on a key food, fruit of the baobab tree (Adansonia digitata). Materials and Methods Proximity of fruiting baobab trees to anthropogenic landmarks were compared to food intake, feeding rate, and behavioral indicators of fear in adult males (N = 11) at Fongoli. Additionally, we compared foraging to vegetative habitats, baobab ripe fruit nutritive quality, surface water availability, and foraging party composition. Results Fruit abundance increased with proximity to anthropogenic landmarks, and chimpanzees exhibited higher frequencies of antipredator behaviors as they approached these risky areas. However, predation risk did not deter adult males from visiting these fruiting trees; instead, risky foraging bouts were associated with higher food intakes and longer feeding times. Additionally, higher feeding rates were observed in open‐canopy habitats, and this behavior may have minimized their risk of heat stress. Conclusions Adaptations that minimize predation risk are widespread in mammalian prey species, but these traits are poorly understood in chimpanzees. Great apes encounter few nonhuman predators capable of successfully capturing and killing them; thus, such events are rarely observed. Although people rarely hunt chimpanzees in Senegal, we found that adult males perceived humans as predators and adjusted their behavior while foraging in risky habitats. From an applied perspective, risk‐taking behavior is important for understanding and mitigating the problem of crop‐feeding in locations where chimpanzees and humans live in sympatry.

  March 28, 2017   doi: 10.1002/ajpa.23221   open full text
• Quantification of the position and depth of the flexor hallucis longus groove in euarchontans, with implications for the evolution of primate positional behavior.
  Gabriel S. Yapuncich, Erik R. Seiffert, Doug M. Boyer.
  American Journal of Physical Anthropology. March 27, 2017
  Objective On the talus, the position and depth of the groove for the flexor hallucis longus tendon have been used to infer phylogenetic affinities and positional behaviors of fossil primates. This study quantifies aspects of the flexor hallucis longus groove (FHLG) to test if: (1) a lateral FHLG is a derived strepsirrhine feature, (2) a lateral FHLG reflects inverted and abducted foot postures, and (3) a deeper FHLG indicates a larger muscle. Methods We used linear measurements of microCT‐generated models from a sample of euarchontans (n = 378 specimens, 125 species) to quantify FHLG position and depth. Data are analyzed with ANOVA, Ordinary and Phylogenetic Generalized Least Squares, and Bayesian Ancestral State Reconstruction (ASR). Results Extant strepsirrhines, adapiforms, plesiadapiforms, dermopterans, and Ptilocercus exhibit lateral FHLGs. Extant anthropoids, subfossil lemurs, and Tupaia have medial FHLGs. FHLGs of omomyiforms and basal fossil anthropoids are intermediate between those of strepsirrhines and extant anthropoids. FHLG position has few correlations with pedal inversion features. Relative FHLG depth is not significantly correlated with body mass. ASRs support a directional model for FHLG position and a random walk model for FHLG depth. Conclusions The prevalence of lateral FHLGs in many non‐euprimates suggests a lateral FHLG is not a derived strepsirrhine feature. The lack of correlations with pedal inversion features suggests a lateral FHLG is not a sufficient indicator of strepsirrhine‐like foot postures. Instead, a lateral FHLG may reduce the risk of tendon displacement in abducted foot postures on large diameter supports. A deep FHLG does not indicate a larger muscle, but likely reduces bowstringing during plantarflexion.

  March 27, 2017   doi: 10.1002/ajpa.23213   open full text
• Horticultural activity predicts later localized limb status in a contemporary pre‐industrial population.
  Jonathan Stieglitz, Benjamin C. Trumble, Hillard Kaplan, Michael Gurven.
  American Journal of Physical Anthropology. March 27, 2017
  Objectives Modern humans may have gracile skeletons due to low physical activity levels and mechanical loading. Tests using pre‐historic skeletons are limited by the inability to assess behavior directly, while modern industrialized societies possess few socio‐ecological features typical of human evolutionary history. Among Tsimane forager‐horticulturalists, we test whether greater activity levels and, thus, increased loading earlier in life are associated with greater later‐life bone status and diminished age‐related bone loss. Materials and Methods We used quantitative ultrasonography to assess radial and tibial status among adults aged 20+ years (mean ± SD age = 49 ± 15; 52% female). We conducted systematic behavioral observations to assess earlier‐life activity patterns (mean time lag between behavioural observation and ultrasound = 12 years). For a subset of participants, physical activity was again measured later in life, via accelerometry, to determine whether earlier‐life time use is associated with later‐life activity levels. Anthropometric and demographic data were collected during medical exams. Results Structural decline with age is reduced for the tibia (female: −0.25 SDs/decade; male: 0.05 SDs/decade) versus radius (female: −0.56 SDs/decade; male: −0.20 SDs/decade), which is expected if greater loading mitigates bone loss. Time allocation to horticulture, but not hunting, positively predicts later‐life radial status (βHorticulture = 0.48, p = 0.01), whereas tibial status is not significantly predicted by subsistence or sedentary leisure participation. Discussion Patterns of activity‐ and age‐related change in bone status indicate localized osteogenic responses to loading, and are generally consistent with the logic of bone functional adaptation. Nonmechanical factors related to subsistence lifestyle moderate the association between activity patterns and bone structure.

  March 27, 2017   doi: 10.1002/ajpa.23214   open full text
• The dawn of dentistry in the late upper Paleolithic: An early case of pathological intervention at Riparo Fredian.
  Gregorio Oxilia, Flavia Fiorillo, Francesco Boschin, Elisabetta Boaretto, Salvatore A. Apicella, Chiara Matteucci, Daniele Panetta, Rossella Pistocchi, Franca Guerrini, Cristiana Margherita, Massimo Andretta, Rita Sorrentino, Giovanni Boschian, Simona Arrighi, Irene Dori, Giuseppe Mancuso, Jacopo Crezzini, Alessandro Riga, Maria C. Serrangeli, Antonino Vazzana, Piero A. Salvadori, Mariangela Vandini, Carlo Tozzi, Adriana Moroni, Robin N. M. Feeney, John C. Willman, Jacopo Moggi‐Cecchi, Stefano Benazzi.
  American Journal of Physical Anthropology. March 27, 2017
  Objectives Early evidence for the treatment of dental pathology is found primarily among food‐producing societies associated with high levels of oral pathology. However, some Late Pleistocene hunter‐gatherers show extensive oral pathology, suggesting that experimentation with therapeutic dental interventions may have greater antiquity. Here, we report the second earliest probable evidence for dentistry in a Late Upper Paleolithic hunter‐gatherer recovered from Riparo Fredian (Tuscany, Italy). Materials and Methods The Fredian 5 human consists of an associated maxillary anterior dentition with antemortem exposure of both upper first incisor (I1) pulp chambers. The pulp chambers present probable antemortem modifications that warrant in‐depth analyses and direct dating. Scanning electron microscopy, microCT and residue analyses were used to investigate the purported modifications of external and internal surfaces of each I1. Results The direct date places Fredian 5 between 13,000 and 12,740 calendar years ago. Both pulp chambers were circumferentially enlarged prior to the death of this individual. Occlusal dentine flaking on the margin of the cavities and striations on their internal aspects suggest anthropic manipulation. Residue analyses revealed a conglomerate of bitumen, vegetal fibers, and probable hairs adherent to the internal walls of the cavities. Discussion The results are consistent with tool‐assisted manipulation to remove necrotic or infected pulp in vivo and the subsequent use of a composite, organic filling. Fredian 5 confirms the practice of dentistry—specifically, a pathology‐induced intervention—among Late Pleistocene hunter‐gatherers. As such, it appears that fundamental perceptions of biomedical knowledge and practice were in place long before the socioeconomic changes associated with the transition to food production in the Neolithic.

  March 27, 2017   doi: 10.1002/ajpa.23216   open full text
• Shifting diet, shifting culture? A bioarchaeological approach to island dietary development on Iron‐Age Öland, Baltic Sea.
  Helene Wilhelmson.
  American Journal of Physical Anthropology. March 27, 2017
  Objectives The diet and subsistence in Iron‐Age Öland is debated as earlier studies and different archaeological sources seemingly provide conflicting interpretations. The objectives of this study are therefore to: (i) add new insights on diet and (ii) investigate the chronological variation in detail. It is common in studies of diet to investigate differences between datasets defined by archaeological periods (determined by artefact typology), but it is rare to explore whether these dietary changes are, in fact, well correlated with these temporal categories or not. Materials and methods Stable isotope analysis of 108 individuals and 25 animals was used to interpret diet in comparison with data from earlier studies. Different values of TLE (Trophic Level Effect) for δ15N were compared for interpretations of diet. Of the 108 individuals, 42 were subjected to 14C analysis in this study. Results The isotopes from Iron‐Age animals on Öland indicate that the local, contemporary ecology is specific. The human isotope values show chronological development both when pooled in chronological groups by typology and by more specific 14C chronology. Discussion The new samples of animals as well as the use of 5‰ TLE for δ15N values results in the diet reinterpreted as mainly domesticate‐based, with at least two shifts in diet occurring in the Iron Age. The use of 14C dates in connection with the stable isotope results indicates a dietary transition occurring between 200 BC and AD 200, a date range that spans two typologically determined time periods.

  March 27, 2017   doi: 10.1002/ajpa.23204   open full text
• Second‐to‐fourth digit ratio (2D:4D) is unrelated to measures of somatic reproductive effort among young men from Cebu, the Philippines.
  Alexander V. Georgiev, Calen P. Ryan, Lee T. Gettler, Thomas W. McDade, Christopher W. Kuzawa.
  American Journal of Physical Anthropology. March 27, 2017
  Objectives A low second‐to‐fourth (2D:4D) digit ratio, a retrospective marker of high prenatal androgens, predicts increased investment in costly sexually dimorphic traits in men in some studies, although results are mixed. Here we test the hypothesis that the association of low 2D:4D ratios with increased muscularity and decreased adiposity depends on current testosterone (T) levels, such that digit ratio will be a particularly strong predictor of outcomes among men exhibiting a mating‐effort‐oriented endocrinological profile (high T). We also test the association between 2D:4D and somatic traits independently of T. Materials and methods We related 2D:4D digit ratios, and their interaction with T, to handgrip strength, lean mass, arm muscle area, and skinfold thickness in a sample of young, childess men (20–22 y) from Cebu, Philippines (N = 623). Results Digit ratio did not significantly predict men's T‐dependent somatic traits. Interactions between 2D:4D and morning T, similarly, did not predict male muscularity or adiposity. Although two of the interactions were significant or marginally significant (p < .1), after adjusting for multiple testing the evidence in support of our hypothesis was weak. Discussion We found no evidence that 2D:4D predicted measures of somatic reproductive effort in this sample of young men from Cebu, who as a group could be considered mostly mating‐oriented. These relationships were also not contingent upon, or stronger, when considering the moderating effect of concurrent T levels. In this sample, 2D:4D was therefore either a poor proxy of prenatal androgen exposure or prenatal androgens had limited influence on adult somatic outcomes.

  March 27, 2017   doi: 10.1002/ajpa.23215   open full text
• Ancestry dynamics in a South American population: The impact of gene flow and preferential mating.
  Philip W. Hedrick.
  American Journal of Physical Anthropology. March 27, 2017
  Objectives European ancestry in many populations in Latin America at autosomal loci is often higher than that from X‐linked loci indicating more European male ancestry and more Amerindian female ancestry. Generally, this has been attributed to more European male gene flow but could also result from an advantage to European mating or reproductive success. Methods Population genetic models were developed to investigate the dynamics of gene flow and mating or reproductive success. Using estimates of autosomal and X‐chromosome European ancestry, the amount of male gene flow or mating or reproductive advantage for Europeans, or those with European ancestry, was estimated. Results In a population from Antioquia, Colombia with an estimated 79% European autosomal ancestry and an estimated 69% European X‐chromosome ancestry, about 15% male gene flow from Europe or about 20% mating or reproductive advantage of Europeans over Amerindians resulted in these levels of European ancestry in the contemporary population. Combinations of gene flow and mating advantage were nearly additive in their impact. Conclusions Gene flow, mating advantage, or a combination of both factors, are consistent with observed levels of European ancestry in a Latin American population. This approach provides a general methodology to determine the levels of gene flow and mating differences that can explain the observed contemporary differences in ancestry from autosomes and X‐chromosomes.

  March 27, 2017   doi: 10.1002/ajpa.23220   open full text
• East of the Andes: The genetic profile of the Peruvian Amazon populations.
  T. Di Corcia, C. Sanchez Mellado, T. J. Davila Francia, G. Ferri, S. Sarno, D. Luiselli, O. Rickards.
  American Journal of Physical Anthropology. March 25, 2017
  Objectives Assuming that the differences between the Andes and the Amazon rainforest at environmental and historical levels have influenced the distribution patterns of genes, languages, and cultures, the maternal and paternal genetic reconstruction of the Peruvian Amazon populations was used to test the relationships within and between these two extreme environments. Materials and Methods We analyzed four Peruvian Amazon communities (Ashaninka, Huambisa, Cashibo, and Shipibo) for both Y chromosome (17 STRs and 8 SNPs) and mtDNA data (control region sequences, two diagnostic sites of the coding region, and one INDEL), and we studied their variability against the rest of South America. Results We detected a high degree of genetic diversity in the Peruvian Amazon people, both for mtDNA than for Y chromosome, excepting for Cashibo people, who seem to have had no exchanges with their neighbors, in contrast with the others communities. The genetic structure follows the divide between the Andes and the Amazon, but we found a certain degree of gene flow between these two environments, as particularly emerged with the Y chromosome descent cluster's (DCs) analysis. Discussion The Peruvian Amazon is home to an array of populations with differential rates of genetic exchanges with their neighbors and with the Andean people, depending on their peculiar demographic histories. We highlighted some successful Y chromosome lineages expansions originated in Peru during the pre‐Columbian history which involved both Andeans and Amazon Arawak people, showing that at least a part of the Amazon rainforest did not remain isolated from those exchanges.

  March 25, 2017   doi: 10.1002/ajpa.23209   open full text
• Technical intelligence and culture: Nut cracking in humans and chimpanzees.
  Christophe Boesch, Daša Bombjaková, Adam Boyette, Amelia Meier.
  American Journal of Physical Anthropology. March 23, 2017
  Objectives According to the technical intelligence hypothesis, humans are superior to all other animal species in understanding and using tools. However, the vast majority of comparative studies between humans and chimpanzees, both proficient tool users, have not controlled for the effects of age, prior knowledge, past experience, rearing conditions, or differences in experimental procedures. We tested whether humans are superior to chimpanzees in selecting better tools, using them more dexteriously, achieving higher performance and gaining access to more resource as predicted under the technical intelligence hypothesis. Materials and methods Aka and Mbendjele hunter‐gatherers in the rainforest of Central African Republic and the Republic of Congo, respectively, and Taï chimpanzees in the rainforest of Côte d'Ivoire were observed cracking hard Panda oleosa nuts with different tools, as well as the soft Coula edulis and Elaeis guinensis nuts. The nut‐cracking techniques, hammer material selection and two efficiency measures were compared. Results As predicted, the Aka and the Mbendjele were able to exploit more species of hard nuts in the forest than chimpanzees. However, the chimpanzees were sometimes more efficient than the humans. Social roles differed between the two species, with the Aka and especially the Mbendjele exhibiting cooperation between nut‐crackers whereas the chimpanzees were mainly individualistic. Discussion Observations of nut‐cracking by humans and chimpanzees only partially supported the technical intelligence hypothesis as higher degrees of flexibility in tool selection seen in chimpanzees compensated for use of less efficient tool material than in humans. Nut cracking was a stronger social undertaking in humans than in chimpanzees.

  March 23, 2017   doi: 10.1002/ajpa.23211   open full text
• Limb bone allometry in modern Euro‐Americans.
  R. L. Jantz, L. Meadows Jantz.
  American Journal of Physical Anthropology. March 20, 2017
  Objectives The pattern of static and secular allometry was examined in a time series of limb bone lengths from individuals with birth years ranging from 1840 to 1989. The main hypothesis investigated was that secular changes in limb proportions, as seen in changes in the brachial and crural indices, can be explained by allometric responses to increasing size. Materials and Methods Maximum lengths of humerus, radius, femur, and tibia were obtained from 19th and 20th centuries identified skeletons. Allometry was investigated on two levels, static and secular. Static allometry was defined as average allometry within 20‐year birth cohorts, and secular allometry as allometry among birth year cohorts. Allometry was assessed by extracting eigenvectors from covariance matrices of log transformed variables. Departures from allometry were examined using shape variables, and principal components of minor axes. Results Static covariance matrices were homogeneous. Eigenvectors extracted from the secular covariance matrix showed important departures from static allometry, particularly a much stronger negative allometry of the humerus and a stronger positive allometry of the tibia. Shape analysis showed that relative humerus length decreased significantly over the time period examined and relative tibia length increased. The last principal component, which combined aspects of the brachial and crural index, showed the highest variation among birth year cohorts. Discussion The results demonstrate that the secular changes in limb proportions cannot be explained by allometric responses to increasing size alone. The majority of variation among birth cohorts is found on the last PC and that suggests that canalized development has been disrupted by the unique environment in which modern Americans now live.

  March 20, 2017   doi: 10.1002/ajpa.23203   open full text
• Developmental changes in feeding behaviors of infant chimpanzees at Mahale, Tanzania: Implications for nutritional independence long before cessation of nipple contact.
  Takuya Matsumoto.
  American Journal of Physical Anthropology. March 20, 2017
  Objectives Weaning of chimpanzees is considered to occur at 4–5‐years‐old with complete cessation of nipple contact and timing of reconception calculated by inter‐birth interval minus gestation length. This is also the basis of “early weaning” in humans (i.e., approximately 2.5‐years‐old). However, recent studies of the survival of orphans and the first molar (M1) eruption in wild chimpanzees have predicted that infants move toward nutritional independence at 3‐years‐old. Therefore, this study aimed to investigate ontogeny of feeding behavior at around 3‐years‐old in wild infant chimpanzees. Materials and methods I studied 19 infants aged 1–60 months in the M group in Mahale Mountains National Park, Tanzania. The total observation time was 518 h, 25 min. Results At around 3‐years‐old, infant chimpanzees spent more total feeding time, and time feeding on leaves, and food physically difficult to process without food transfer from other individuals. These results suggest that infant chimpanzees significantly reduced their dependence on milk for nutrition at around 3‐years‐old, that is, before cessation of nipple contact. Discussion This study suggests that M1 eruption in wild Eastern Chimpanzees is an index of the period when infants move toward nutritional independence with a key dietary transition. This is the first study to provide behavioral evidence of the large temporal gap between nutritional independence of infants and reconception of mothers in great apes, and clarify the unique feature of human life history whereby mothers can reconceive before an infant reaches nutritional independence.

  March 20, 2017   doi: 10.1002/ajpa.23212   open full text
• Ontogenetic changes in limb postures and their impact on effective limb length in baboons (Papio cynocephalus).
  Angel Zeininger, Liza J. Shapiro, David A. Raichlen.
  American Journal of Physical Anthropology. March 16, 2017
  Objectives Digitigrade hand and foot postures and extended elbows and knees are considered adaptations to running in cursorial mammals because they increase effective limb lengths (ELLs). However, the relationship between digitigrady and ELL in primates is not well understood. We documented the ontogeny of limb postures in baboons to better understand the function of digitigrady during walking. We hypothesized that the hand and foot would become more elevated and the elbow and knee more extended, leading to increased relative ELLs throughout ontogeny. Materials and Methods Longitudinal kinematic data were collected on four infant yellow baboons (Papio cynocephalus) as they aged from two to nine months, and again at two to three years. Hand/foot postures, elbow/knee angles, relative fore/hind limb ELLs, and dimensionless velocity were measured for 404 symmetrical walking strides. Results Digitigrade hand and foot postures were preferred at all ages. The elbow extended slightly and the knee flexed slightly with age. Elevated proximal hands, extended elbows, and extended knees were associated with long relative ELLs. For a given age, relative hind limb ELL was longer than relative forelimb ELL. Discussion In the forelimb, digitigrade hand postures and extended elbows function to increase relative ELL at slow walking velocity. Increased forelimb ELL may be an attempt to equalize forelimb and hind limb ELLs in baboons with an absolutely longer hind limb. Pedal digitigrady is not a main contributing factor to hind limb ELL. Results suggest that manual and pedal digitigrady in terrestrial cercopithecoids does not function to increase velocity.

  March 16, 2017   doi: 10.1002/ajpa.23201   open full text
• A test of a skeletal ageing method based on resorption of the alveolar crest following tooth loss using a skeletal population of documented age at death.
  Simon Mays.
  American Journal of Physical Anthropology. March 16, 2017
  Objectives Resorption of the alveolar process occurs following tooth loss, and appears to continue for a prolonged period. Previous study (Mays, ) with a known‐age collection of human remains suggested the potential of this phenomenon for age estimation in remains of adults who have lost one or more molar teeth. This article tests this ageing technique on another known age group, and attempts to evaluate the impact of some extraneous factors on the method. Materials and methods The study group comprises adult skeletons (N = 110) of documented age at death from 18th to 19th century London. It examines the relationship between a previously described standardized measure of posterior corpus height (SPCH) in mandibles showing loss of one or more molars. The potential influence of a general tendency to form or lose bone (identified by the presence of ossification into the anterior longitudinal ligament of the spine and cortical thickness at the metacarpal) and (for females) parity are also investigated. Results Negative age correlation was found for SPCH in females but not in males. In females, the age‐association was weaker, and the rate of loss slower, than in a previously studied 19th century European population. None of the other factors investigated showed a relationship with SPCH. Discussion As with other bony age indicators, the relationship between SPCH and age varies in different populations. Further work is needed to evaluate the extraneous factors that affect the relationship with age.

  March 16, 2017   doi: 10.1002/ajpa.23202   open full text
• Age‐related changes of sulcal imprints on the endocranium in the Japanese macaque (Macaca fuscata).
  Nguyen Minh, Yuzuru Hamada.
  American Journal of Physical Anthropology. March 16, 2017
  Objectives The degree of expression of sulcal patterns on endocasts of nonhuman primates has been shown to depend primarily on species (brain size) and age of the individual. It has been suggested that brain details on endocasts are reproduced better in juvenile than adult primates. Here, we investigated age‐related changes in the imprint of the major sulci on the endocranium of Japanese macaques (Macaca fuscata) from the juvenile period to adulthood. Materials and methods Using CT scans of 25 (12 males, 13 females) cranial specimens from macaques, we generated virtual endocasts to assess imprints of the seven main sulci on the endocranial surface. Expression of each sulcal imprint was evaluated by imprint score method. Results The degree of expression of sulcal imprints differed between sulci. Arcuate, superior temporal, and principal sulci were well defined, whereas lunate and intraparietal sulci were poorly represented. Sulcal imprints showed significant age‐related changes in Japanese macaques from juvenile to elderly. Sulcal imprints showed a slight decrease in degree of expression from the juvenile period (2–4 years) to adolescence (4–6 years), and then remained unchanged until mid‐adulthood (15–16 years). The degree of expression of the sulcal imprints significantly decreased from mid‐adulthood to old age (>20 years). Conclusions The degree of expression of the sulcal imprints (relief forms) in inner table bone surface (endocranium) reveals significant age‐related decreases in adults. The great decrease starts at around 20 years of age. The endocranial volume showed a significant age‐related increase, and thus, it is suggested that the endocranial surface in macaques may be resorbed with advancing age.

  March 16, 2017   doi: 10.1002/ajpa.23205   open full text
• Androgen receptor polyglutamine repeat length (AR‐CAGn) modulates the effect of testosterone on androgen‐associated somatic traits in Filipino young adult men.
  Calen P. Ryan, Alexander V. Georgiev, Thomas W. McDade, Lee T. Gettler, Dan T. A. Eisenberg, Margarita Rzhetskaya, Sonny S. Agustin, M. Geoffrey Hayes, Christopher W. Kuzawa.
  American Journal of Physical Anthropology. March 14, 2017
  Objectives The androgen receptor (AR) mediates expression of androgen‐associated somatic traits such as muscle mass and strength. Within the human AR is a highly variable glutamine short‐tandem repeat (AR‐CAGn), and CAG repeat number has been inversely correlated to AR transcriptional activity in vitro. However, evidence for an attenuating effect of long AR‐CAGn on androgen‐associated somatic traits has been inconsistent in human populations. One possible explanation for this lack of consistency is that the effect of AR‐CAGn on AR bioactivity in target tissues likely varies in relation to circulating androgen levels. Materials and Methods We tested whether relationships between AR‐CAGn and several androgen‐associated somatic traits (waist circumference, lean mass, arm muscle area, and grip strength) were modified by salivary (waking and pre‐bed) and circulating (total) testosterone (T) levels in young adult males living in metropolitan Cebu, Philippines (n = 675). Results When men's waking T was low, they had a reduction in three out of four androgen‐associated somatic traits with lengthening AR‐CAGn (p < .1), consistent with in vitro research. However, when waking T was high, we observed the opposite effect—lengthening AR‐CAGn was associated with an increase in these same somatic traits. Discussion Our finding that longer AR‐CAGn predicts greater androgen‐associated trait expression among high‐T men runs counter to in vitro work, but is generally consistent with the few prior studies to evaluate similar interactions in human populations. Collectively, these results raise questions about the applicability of findings derived from in vitro AR‐CAGn studies to the receptor's role in maintaining androgen‐associated somatic traits in human populations.

  March 14, 2017   doi: 10.1002/ajpa.23208   open full text
• Stable and fluctuating social preferences and implications for cooperation among female bonobos at LuiKotale, Salonga National Park, DRC.
  Liza R. Moscovice, Pamela Heidi Douglas, Laura Martinez‐Iñigo, Martin Surbeck, Linda Vigilant, Gottfried Hohmann.
  American Journal of Physical Anthropology. March 09, 2017
  Objectives Female bonobos (Pan paniscus) are characterized as highly affiliative and cooperative, but few studies have quantified the strength and stability of female intra‐sexual relationships or explored how variation in social relationships influences cooperation. We measure female social preferences, identify causes of variation in preferences, and test whether variation in social preferences predicts food sharing or coalitionary support. Methods Data were collected over 3 years from females in the Bompusa community at LuiKotale, DRC. We measured genetic relatedness and constructed social preference indices for party association, proximity, grooming, GG‐rubbing and aggression. We identified preferred social partners based on permutation tests and measured stability using Mantel tests. We used factor analysis to identify inter‐relationships between preference indices and used LMMs to test whether variation in social preferences was explained by relatedness, rank differences, having dependent young or co‐residency time. We used GLMMs to test whether variation in social preferences predicted food sharing or coalitionary support. Results All females had preferred non‐kin partners for proximity, grooming or GG‐rubbing, but only grooming preferences were stable across years. Association indices were higher among lactating females, and aggression was lower among females with longer co‐residency times. The factor analysis identified one factor, representing proximity and GG‐rubbing preferences, labeled behavioral coordination. Dyads with higher levels of behavioral coordination were more likely to share food. Conclusions Female bonobos exhibit stable, differentiated grooming relationships outside of kinship and philopatry. Females also exhibit flexible proximity and GG‐rubbing preferences that may facilitate cooperation with a wider range of social partners.

  March 09, 2017   doi: 10.1002/ajpa.23197   open full text
• Patterns of long bone growth in a mid‐19th century documented sample of the urban poor from Bethnal Green, London, UK.
  Rachel Ives, Louise Humphrey.
  American Journal of Physical Anthropology. March 09, 2017
  Objectives Studies of male and female long bone growth in past populations are limited and usually constrained by the lack of personal identification. This article aimed to evaluate long bone growth in a series of mid‐19th century documented burials associated with the urban poor from Bethnal Green, London, UK. Materials and methods Maximum diaphyseal lengths from 74 males and 70 females (2 months to 12 years) were compared to modern reference data from North America. Diaphyseal lengths were expressed as a percentage of expected length and an average percentage value was calculated across all available long bones. An index of growth progression was introduced to explore differences in the progress of males and females towards their projected adult size. Results Deviation from the expected growth attainment was evident in both sexes in the archaeological series by 2–4 months of age. Only 19.4% (28/144) of the children had attained an average long bone length >90% of the predicted mean in the reference series. The percentage of expected growth attainment decreased steadily in both sexes during infancy and early childhood. Overall, females deviated further from their expected growth progression than males. Discussion Growth faltering in both males and females was established during infancy (<1 year) with no evidence for recovery in older age groups. Early weaning and inadequate artificial feeding, together with impoverished living conditions and limited sanitary provision, most likely impacted on childhood growth.

  March 09, 2017   doi: 10.1002/ajpa.23198   open full text
• A radiographic study of permanent molar development in wild Virunga mountain gorillas of known chronological age from Rwanda.
  Alexandra E. Kralick, M. Loring Burgess, Halszka Glowacka, Keely Arbenz‐Smith, Kate McGrath, Christopher B. Ruff, King Chong Chan, Michael R. Cranfield, Tara S. Stoinski, Timothy G. Bromage, Antoine Mudakikwa, Shannon C. McFarlin.
  American Journal of Physical Anthropology. March 02, 2017
  Objectives While dental development is important to life history investigations, data from wild known‐aged great apes are scarce. We report on the first radiographic examination of dental development in wild Virunga mountain gorillas, using known‐age skeletal samples recovered in Rwanda. Materials and methods In 43 individuals (0.0–14.94 years), we collected radiographs of mandibular molars, and where possible, cone beam CT scans. Molar crown and root calcification status was assessed using two established staging systems, and age prediction equations generated using polynomial regression. Results were compared to available data from known‐age captive and wild chimpanzees. Results Mountain gorillas generally fell within reported captive chimpanzee distributions or exceeded them, exhibiting older ages at equivalent radiographic stages of development. Differences reflect delayed initiation and/or an extended duration of second molar crown development, and extended first and second molar root development, in mountain gorillas compared to captive chimpanzees. However, differences in the duration of molar root development were less evident compared to wild chimpanzees. Discussion Despite sample limitations, our findings extend the known range of variation in radiographic estimates of molar formation timing in great apes, and provide a new age prediction technique based on wild specimens. However, mountain gorillas do not appear accelerated in radiographic assessment of molar formation compared to chimpanzees, as they are for other life history traits. Future studies should aim to resolve the influence of species differences, wild versus captive environments, and/or sampling phenomena on patterns observed here, and more generally, how they relate to variation in tooth size, eruption timing, and developmental life history.

  March 02, 2017   doi: 10.1002/ajpa.23192   open full text
• A giant among dwarfs: a new species of galago (Primates: Galagidae) from Angola.
  Magdalena S. Svensson, Elena Bersacola, Michael S. L. Mills, Rachel A. Munds, Vincent Nijman, Andrew Perkin, Judith C. Masters, Sébastien Couette, K. Anne‐Isola Nekaris, Simon K. Bearder.
  American Journal of Physical Anthropology. February 22, 2017
  Objectives Based on vocalization recordings of an unknown galago species, our main objectives were to compare morphology and call structure with known closely‐related taxa and describe a new species of galago. Materials and methods We conducted field surveys in three forest habitats along the escarpment region in western Angola (Kumbira Forest, Bimbe Area, and Northern Scarp Forest), and examined galago specimens from museums worldwide. We digitized and analyzed calls using Avisoft SASLab Pro software. We also compared museum specimens from Angola with other Galago and Galagoides specimens, and conducted comparative analyses (ANOVA and between group principle component analysis) based on a set of twelve linear measurements of skulls and teeth. Results We describe the new species to which we give the name Angolan dwarf galago, Galagoides kumbirensis sp. nov. The new species has a loud and characteristic crescendo call, used by other Galagoides spp. (sensu stricto) in West Africa to attract companions and repel rivals. However, this call shows species‐typical differences from its closest relatives. Galagoides kumbirensis sp. nov. is also distinguished by differences in the skull morphology, pelage color and facial markings, as well as a larger body size, similar to that of Galago moholi, which is not known to be sympatric. Conclusion This discovery points to the importance of Angolan forests as refuges for endemic biodiversity. These forests are under severe threat from overexploitation, and there is an urgent need to establish conservation measures and designate protected areas.

  February 22, 2017   doi: 10.1002/ajpa.23175   open full text
• Smooth operator: The effects of different 3D mesh retriangulation protocols on the computation of Dirichlet normal energy.
  Jackson P. Spradley, James D. Pampush, Paul E. Morse, Richard F. Kay.
  American Journal of Physical Anthropology. February 20, 2017
  Objectives Dirichlet normal energy (DNE) is a metric of surface topography that has been used to evaluate the relationship between the surface complexity of primate cheek teeth and dietary categories. This study examines the effects of different 3D mesh retriangulation protocols on DNE. We examine how different protocols influence the DNE of a simple geometric shape—a hemisphere—to gain a more thorough understanding than can be achieved by investigating a complex biological surface such as a tooth crown. Materials and Methods We calculate DNE on 3D surface meshes of hemispheres and on primate molars subjected to various retriangulation protocols, including smoothing algorithms, smoothing amounts, target face counts, and criteria for boundary face exclusion. Software used includes R, MorphoTester, Avizo, and MeshLab. DNE was calculated using the R package “molaR.” Results In all cases, smoothing as performed in Avizo sharply decreases DNE initially, after which DNE becomes stable. Using a broader boundary exclusion criterion or performing additional smoothing (using “mesh fairing” methods) further decreases DNE. Increasing the mesh face count also results in increased DNE on tooth surfaces. Conclusions Different retriangulation protocols yield different DNE values for the same surfaces, and should not be combined in meta‐analyses. Increasing face count will capture surface microfeatures, but at the expense of computational speed. More aggressive smoothing is more likely to alter the essential geometry of the surface. A protocol is proposed that limits potential artifacts created during surface production while preserving pertinent features on the occlusal surface.

  February 20, 2017   doi: 10.1002/ajpa.23188   open full text
• The relative position of the human fibula to the tibia influences cross‐sectional properties of the tibia.
  Benjamin M. Auerbach, Alice F. Gooding, Colin N. Shaw, Adam D. Sylvester.
  American Journal of Physical Anthropology. February 20, 2017
  Objectives The fibula transmits loads within the lower limb of hominids. The few studies of variation in the cross‐sectional geometric (CSG) properties of the fibula have established differences in its rigidity among groups engaged in distinct habitual loading activities. This study adds to this research by considering the relationship between CSG properties and the anatomical position of the fibula relative to the tibia among groups with differences in documented activity patterns. Material and methods We used pQCT scans taken at 50% of the length of the lower leg in 83 healthy young adult collegiate‐aged individuals divided into five activity groups: runners, swimmers, cricketers, field hockey players, and non‐athletes. We compared variation in calculated CSG properties against the distance between fibular and tibial centroids, as well as the angle of that plane relative to the plane of tibial Imax. Results Tibial and fibular CSG properties vary with respect to the relative position of the two bones. Tibial CSG properties differ in concert with the relative angle of the fibula to tibial Imax, while fibular CSG properties differ with the distance between the elements. Fibulae are more posterior‐medially positioned in groups engaged in terrestrial athletics than among swimmers. Discussion The tibia and fibula experience different loads. The relative position of the two bones leads to compensatory differences in their CSG properties, perhaps due to increased resistance to bending in fibulae with greater distances from the tibia. Examinations of tibial CSG properties without considering the fibula limits interpretations about activity.

  February 20, 2017   doi: 10.1002/ajpa.23196   open full text
• Morphological variation among late holocene Mexicans: Implications for discussions about the human occupation of the Americas.
  Brianne Herrera, Daniel Peart, Nicole Hernandez, Kate Spradley, Mark Hubbe.
  American Journal of Physical Anthropology. February 20, 2017
  Objectives Cranial morphology has previously been used to estimate phylogenetic relationships among populations, and has been an important tool in the reconstruction of ancient human dispersals across the planet. In the Americas, previous morphological studies support a scenario of people entering the Americas and dispersing from North America into South America through Meso America, making the Mexican territory the natural funnel through which biological diversity entered South America. Materials and methods We explore the cranial morphological affinities of three late Holocene Mexican series, in relation to ancient and modern crania from North and South America, Australo‐Melanesia, and East Asia. Morphological affinities were assessed through Mahalanobis Distances, and represented via Multidimensional Scaling and Ward's Linkage Cluster analysis. Minimum FST values were also calculated for each series. Results Our results show Mexican groups share morphological affinities with the Native American series, but do not cluster together as would be expected. The minimum FST estimates show between‐group variation in the Americas is higher than the Asian or Australo‐Melanesian populations, and that Mexican series have high between‐group variance (FST = 0.124), compared to the geographically larger South America (FST = 0.116) and North America (FST = 0.076). Discussion These results show that the Mexican series share morphological affinities with the East Asian series, but maintains high levels of between‐group variation, similar to South America. This supports the suggestion that the high phenotypic variation seen the Americas is not a result of its size, as it can be found in more constricted areas, such as the Mexican territory.

  February 20, 2017   doi: 10.1002/ajpa.23186   open full text
• Subadult sex estimation from diaphyseal dimensions.
  Kyra E. Stull, Ericka N. L'Abbé, Stephen D. Ousley.
  American Journal of Physical Anthropology. February 15, 2017
  Objectives Many studies on subadult sex estimation focus on elements that express sexually dimorphic features in adults. In contrast, diaphyseal dimensions have been shown to display sex‐specific differences prior to adolescence. The current study evaluates the use of diaphyseal dimensions in subadult sex estimation. Materials and Methods Eighteen postcranial measurements from six long bones were collected on Lodox Statscan radiographic images of 1,310 modern South African children between birth and 12 years of age. Linear (LDA) and flexible discriminant analysis (FDA) and logistic regression were employed with single and multiple variable models with age both included and excluded from the model. Bootstrapped cross‐validation was employed because some of the multiple variable subsets had small sample sizes. Each of the bootstrapped accuracies has an associated 95% confidence interval demonstrating the ranges in classification. Results Classification methods utilizing multiple variables achieved the highest bootstrapped classification accuracies (70% to 93%). The inclusion of age in the models did not consistently increase or decrease the classification accuracies. Proximal and distal breadth measurements were consistently recognized as important measurements in model creation. FDA yielded the highest overall accuracies, but the logistic regression presented with overall smaller bootstrapped 95% confidence intervals. Discussion Quantifiable sex differences were discovered in the appendicular skeleton of children between birth and 12 years of age. The high classification accuracies were likely due to using numerous predictor variables from multiple skeletal elements, which were optimized for classification using FDA. To facilitate application, a graphical user interface, KidStats, was developed.

  February 15, 2017   doi: 10.1002/ajpa.23185   open full text
• Racial discrimination associated with higher diastolic blood pressure in a sample of American Indian adults.
  Zaneta M. Thayer, Irene V. Blair, Dedra S. Buchwald, Spero M. Manson.
  American Journal of Physical Anthropology. February 15, 2017
  Objectives Hypertension prevalence is high among American Indians (AIs). AIs experience a substantial burden of interpersonal racial discrimination, which in other populations has been associated with higher blood pressure. The purpose of this study is to understand whether racial discrimination experiences are associated with higher blood pressure in AIs. Materials and Methods We used the Everyday Discrimination Scale to evaluate the relationship between discrimination and measured blood pressure among 77 AIs from two reservation communities in the Northern Plains. We used multivariate linear regression to evaluate the association of racial discrimination with systolic and diastolic blood pressure, respectively. Racial discrimination, systolic blood pressure, and diastolic blood pressure were analyzed as continuous variables. All analyses adjusted for sex, waist circumference, age, posttraumatic stress disorder status, and education. Results We found that 61% of participants experienced discrimination that they attributed to their race or ancestry. Racial discrimination was associated with significantly higher diastolic blood pressure (β = 0.22, SE = 0.09, p = .02), and with a similar non‐significant trend toward higher systolic blood pressure (β = 0.25, SE = 0.15, p = .09). Conclusion The results of this analysis suggest that racial discrimination may contribute to higher diastolic blood pressure within Native communities. These findings highlight one pathway through which the social environment can shape patterns of biology and health in AI and other socially and politically marginalized groups.

  February 15, 2017   doi: 10.1002/ajpa.23190   open full text
• People choose to run at their optimal speed.
  Joseph K. Rathkey, Cara M. Wall‐Scheffler.
  American Journal of Physical Anthropology. February 14, 2017
  Objectives The purpose of this article is to test whether people choose to behave in a manner that reduces the amount of energy they use to travel a given distance. While this has been shown consistently for walking, it has never been tested with human running. Materials and Methods We collected energetic data and lower limb anthropometrics on nine men running at six different running speeds. We collected on all six speeds on 3 different days and took the average of the energetic values for each speed. On each day we also asked the participants to choose the speed at which they could comfortably run for an hour, and we took the average of these preferred speeds. We then fit a 2nd order polynomial to the energetic data and compared the speed at which the minimum cost of transport (SpMinCoT) occurred with their preferred running speed. Results All participants showed a curvilinear relationship between speed and their cost of transport (CoT). Additionally, the preferred speed was not significantly different than the speed at the minCoT (p = 0.215), and the best fit line between the minCoT and the CoT at the preferred speed was y = x (R2 = 0.994). Discussion Humans are able to preferentially identify the speed which minimizes energy expenditure during running, as well as in walking. Over long distances, energy conservation during running would be particularly crucial so further investigations should focus on the mechanisms by which people are able to detect their ‘optimal’ running speeds.

  February 14, 2017   doi: 10.1002/ajpa.23187   open full text
• Reconstructing diet in Napoleon's Grand Army using stable carbon and nitrogen isotope analysis.
  Sammantha Holder, Tosha L. Dupras, Rimantas Jankauskas, Lana Williams, John Schultz.
  American Journal of Physical Anthropology. February 13, 2017
  Objectives Historical evidence has provided information regarding disease and mortality in Napoleon Bonaparte's Grand Army, but dietary information beyond individual soldier accounts remains scarce. The purpose of this research is to reconstruct the diets of Napoleon's multiethnic army who were associated with the Russian Campaign of 1812. Materials and Methods We conducted stable carbon and nitrogen isotope ratio analysis on femoral bone collagen of 78 individuals recovered from a salvage excavation at the mass gravesite of Šiaurės miestelis in Vilnius, Lithuania. These individuals were later discovered to be Napoleonic soldiers and camp followers who participated in the 1812 Russian Campaign. Results Stable carbon isotope ratios range from −19.2‰ to −11.8‰, with a mean of −17.8‰ ± 1.5‰ (1 σ). Stable nitrogen isotope ratios range from 7.1‰ to 13.6‰, with a mean of 10.5‰ ± 1.4‰ (1 σ). Both δ13C and δ15N values show a wide range of variation. Discussion Stable isotope data indicate considerable dietary variation in this population associated with a multiethnic and socially stratified military population. Diets ranged from predominantly C3‐based to predominantly C4‐based, with varying inputs of terrestrial, freshwater, and marine animal protein. Comparison with other European populations further denotes the exceptional range of dietary variation of soldiers and camp followers in Napoleon's army.

  February 13, 2017   doi: 10.1002/ajpa.23184   open full text
• Testing biomechanical models of human lumbar lordosis variability.
  Eric R. Castillo, Connie Hsu, Ross W. Mair, Daniel E. Lieberman.
  American Journal of Physical Anthropology. February 13, 2017
  Objectives Lumbar lordosis (LL) is a key adaptation for bipedalism, but factors underlying curvature variations remain unclear. This study tests three biomechanical models to explain LL variability. Materials and methods Thirty adults (15 male, 15 female) were scanned using magnetic resonance imaging (MRI), a standing posture analysis was conducted, and lumbar range of motion (ROM) was assessed. Three measures of LL were compared. The trunk's center of mass was estimated from external markers to calculate hip moments (Mhip) and lumbar flexion moments. Cross‐sectional areas of lumbar vertebral bodies and trunk muscles were measured from scans. Regression models tested associations between LL and the Mhip moment arm, a beam bending model, and an interaction between relative trunk strength (RTS) and ROM. Results Hip moments were not associated with LL. Beam bending was moderately predictive of standing but not supine LL (R2 = 0.25). Stronger backs and increased ROM were associated with greater LL, especially when standing (R2 = 0.65). The strength‐flexibility model demonstrates the differential influence of RTS depending on ROM: individuals with high ROM exhibited the most LL variation with RTS, while those with low ROM showed reduced LL regardless of RTS. Discussion Hip moments appear constrained suggesting the possibility of selection, and the beam model explains some LL variability due to variations in trunk geometry. The strength‐flexibility interaction best predicted LL, suggesting a tradeoff in which ROM limits the effects of back strength on LL. The strength‐flexibility model may have clinical relevance for spinal alignment and pathology. This model may also suggest that straight‐backed Neanderthals had reduced lumbar mobility.

  February 13, 2017   doi: 10.1002/ajpa.23189   open full text
• Sex‐specific genetic diversity is shaped by cultural factors in Inner Asian human populations.
  Nina Marchi, Tatyana Hegay, Philippe Mennecier, Myriam Georges, Romain Laurent, Mark Whitten, Philipp Endicott, Almaz Aldashev, Choduraa Dorzhu, Firuza Nasyrova, Boris Chichlo, Laure Ségurel, Evelyne Heyer.
  American Journal of Physical Anthropology. February 03, 2017
  Objectives Sex‐specific genetic structures have been previously documented worldwide in humans, even though causal factors have not always clearly been identified. In this study, we investigated the impact of ethnicity, geography and social organization on the sex‐specific genetic structure in Inner Asia. Furthermore, we explored the process of ethnogenesis in multiple ethnic groups. Methods We sampled DNA in Central and Northern Asia from 39 populations of Indo‐Iranian and Turkic‐Mongolic native speakers. We focused on genetic data of the Y chromosome and mitochondrial DNA. First, we compared the frequencies of haplogroups to South European and East Asian populations. Then, we investigated the genetic differentiation for eight Y‐STRs and the HVS1 region, and tested for the effect of geography and ethnicity on such patterns. Finally, we reconstructed the male demographic history, inferred split times and effective population sizes of different ethnic groups. Results Based on the haplogroup data, we observed that the Indo‐Iranian‐ and Turkic‐Mongolic‐speaking populations have distinct genetic backgrounds. However, each population showed consistent mtDNA and Y chromosome haplogroups patterns. As expected in patrilocal populations, we found that the Y‐STRs were more structured than the HVS1. While ethnicity strongly influenced the genetic diversity on the Y chromosome, geography better explained that of the mtDNA. Furthermore, when looking at various ethnic groups, we systematically found a genetic split time older than historical records, suggesting a cultural rather than biological process of ethnogenesis. Conclusions This study highlights that, in Inner Asia, specific cultural behaviors, especially patrilineality and patrilocality, leave a detectable signature on the sex‐specific genetic structure.

  February 03, 2017   doi: 10.1002/ajpa.23151   open full text
• Comparative primate obstetrics: Observations of 15 diurnal births in wild gelada monkeys (Theropithecus gelada) and their implications for understanding human and nonhuman primate birth evolution.
  Nga Nguyen, Laura M. Lee, Peter J. Fashing, Niina O. Nurmi, Kathrine M. Stewart, Taylor J. Turner, Tyler S. Barry, Kadie R. Callingham, C. Barret Goodale, Bryce S. Kellogg, Ryan J. Burke, Emily K. Bechtold, Megan J. Claase, G. Anita Eriksen, Sorrel C.Z. Jones, Jeffrey T. Kerby, Jacob B. Kraus, Carrie M. Miller, Thomas H. Trew, Yi Zhao, Evan C. Beierschmitt, Malcolm S. Ramsay, Jason D. Reynolds, Vivek V. Venkataraman.
  American Journal of Physical Anthropology. February 01, 2017
  Objectives The birth process has been studied extensively in many human societies, yet little is known about this essential life history event in other primates. Here, we provide the most detailed account of behaviors surrounding birth for any wild nonhuman primate to date. Materials and Methods Over a recent ∼10‐year period, we directly observed 15 diurnal births (13 live births and 2 stillbirths) among geladas (Theropithecus gelada) at Guassa, Ethiopia. During each birth, we recorded the occurrence (or absence) of 16 periparturitional events, chosen for their potential to provide comparative evolutionary insights into the factors that shaped birth behaviors in humans and other primates. Results We found that several events (e.g., adopting standing crouched positions, delivering infants headfirst) occurred during all births, while other events (e.g., aiding the infant from the birth canal, licking infants following delivery, placentophagy) occurred during, or immediately after, most births. Moreover, multiparas (n = 9) were more likely than primiparas (n = 6) to (a) give birth later in the day, (b) isolate themselves from nearby conspecifics while giving birth, (c) aid the infant from the birth canal, and (d) consume the placenta. Discussion Our results suggest that prior maternal experience may contribute to greater competence or efficiency during the birth process. Moreover, face presentations (in which infants are born with their neck extended and their face appearing first, facing the mother) appear to be the norm for geladas. Lastly, malpresentations (in which infants are born in the occiput anterior position more typical of human infants) may be associated with increased mortality in this species. We compare the birth process in geladas to those in other primates (including humans) and discuss several key implications of our study for advancing understanding of obstetrics and the mechanism of labor in humans and nonhuman primates.

  February 01, 2017   doi: 10.1002/ajpa.23141   open full text
• Evolution of the hominoid scapula and its implications for earliest hominid locomotion.
  Michael S. Selby, C. Owen Lovejoy.
  American Journal of Physical Anthropology. January 27, 2017
  Objectives The higher primate scapula has been subject to many explanations of the putative “adaptive value” of its individual traits. However, the shift from the bone's position in above branch quadrupeds to its more posterolateral position in recent hominoids obviously required fundamental changes to its general form. We hypothesize that most features argued to be individually adaptive are more likely secondary consequences of changes in its fundamental bauplan, a view more consistent with modern developmental biology. Materials and Methods We tested this hypothesis with scapular metrics and angles from a broad anthropoid sample. Results Our results support our hypothesis. Contrary to earlier predictions, vertebral border length differs little relative to body size in anthropoids, inferior angle position primarily reflects mediolateral scapular breadth, and supraspinous and infraspinous fossa sizes largely reflect scapular spine orientation. Suspensory taxa have cranially oriented glenoids, whereas slow clamberers and humans do not. Australopithecus most closely resembles the latter. Discussion Most scapular features can be explained by only two primary changes: (1) reduction in mediolateral breadth and (2) change in the glenoid position relative to the vertebral border with increased reliance on suspension, which led to a more cranially angled scapular spine. Virtually all other scapular traits appear to be byproducts of these two changes. Based on fossil morphology, hominids1 were derived from a last common ancestor primarily adapted for clambering and not for suspension. Scapular form in early hominids such as Australopithecus is therefore primitive and largely reflects the genus's general clambering heritage.

  January 27, 2017   doi: 10.1002/ajpa.23158   open full text
• Overall trends vs. individual trajectories in the second‐to‐fourth digit (2D:4D) and metacarpal (2M:4M) ratios during puberty and adolescence.
  Miroslav Králík, Pavlína Ingrová, Sławomir Kozieł, Adela Hupková, Ondřej Klíma.
  American Journal of Physical Anthropology. January 25, 2017
  Objectives The second‐to‐fourth digit ratio (2D:4D ratio) can be assumed a valid indicator of sexual differentiation, provided that it is stable once it develops, or eventual changes remain uniform in a respective cohort throughout ontogenesis. The main goal of this study was to determine whether the metacarpal 2M:4M and the digit 2D:4D ratio change during the period of pubertal/adolescent growth. Materials and Methods The metacarpals and digits were measured on radiographs of left hands in the sample of 328 individuals (96 pairs of male and 68 pairs of female twins) from the Wrocław Longitudinal Study of Twins (1967–1983). Five consecutive annual measurements were done for each individual within a 4‐year‐interval somewhere between 7 and 18 years of age. Age‐related changes in both ratios were studied using a set of mixed‐effects linear models. Three types of correlation coefficients were used for assessment of stability between repeated measurements at different ages. Results An overall decrease in the average 2M:4M ratio was observed, attributable to a much larger extent to males than to females. On the contrary, a slight overall increase in the average 2D:4D ratio was observed, attributable to a much larger extent to females than to males. The rank order of the ratios remained highly stable within the monitored period (the correlation coefficient mostly ranged between 0.85 and 0.95). In spite of these findings, we recorded significant intraindividual changes in both ratios. In some individuals the 2D:4D ratio can undergo changes comparable to average sex differences and much higher than average age‐related changes. Discussion Relatively slight overall changes in digit ratio in puberty and adolescence themselves are not inconsistent with the use of the 2D:4D ratio as an indirect marker of prenatal sexual differentiation. Nevertheless, individual changes in the ratios varied substantially in this study and differed from the average trends. Future studies should focus on the nature of interindividual developmental differences in the digit and metacarpal ratios.

  January 25, 2017   doi: 10.1002/ajpa.23153   open full text
• Utility of osteon circularity for determining species and interpreting load history in primates and nonprimates.
  Kendra E. Keenan, Chad S. Mears, John G. Skedros.
  American Journal of Physical Anthropology. January 25, 2017
  Objectives Histomorphological analyses of bones are used to estimate an individual's chronological age, interpret a bone's load history, and differentiate species. Among various histomorphological characteristics that can influence mechanical properties of cortical bone, secondary osteon (Haversian system) population density and predominant collagen fiber orientation are particularly important. Cross‐sectional shape characteristics of secondary osteons (On.Cr = osteon circularity, On.El = osteon ellipticality) are considered helpful in these contexts, but more robust proof is needed. We sought to determine if variations in osteon shape characteristics are sufficient for accurately differentiating species, load‐complexity categories, and regional habitual strain‐mode distributions (e.g., tension vs. compression regions). Materials and Methods Circularly polarized light images were obtained from 100‐micron transverse sections from diaphyses of adult deer calcanei; sheep calcanei, radii, and tibiae; equine calcanei, radii, and third metacarpals (MC3s); chimpanzee femora; and human femora and fibulae. Osteon cross‐sectional area (On.Ar), On.Cr, and On.El were quantified indiscriminately and in the contexts of load‐complexity and regional strain‐mode distributions. Results On.Cr and On.El, when examined independently in terms of all data, or mean (nested) data, for each bone, exceeded 80% accuracy in the inter‐species comparisons only with respect to distinguishing humans from nonhumans. Correct classification among the nonhuman species was <70%. When On.Cr and On.El were coupled together and with On.Ar in discriminant function analyses (nested and unnested data) there were high misclassifications in all but human vs. nonhuman comparisons. Discussion Frequent misclassifications in nonhuman comparisons might reflect influences of habitual load complexity and/or strain‐mode distributions, or other factors not accounted for by these two considerations.

  January 25, 2017   doi: 10.1002/ajpa.23154   open full text
• The seasonal feeding ecology of the javan slow loris (nycticebus javanicus).
  Francis Cabana, Ellen Dierenfeld, Wirdateti Wirdateti, Giuseppe Donati, K.A.I. Nekaris.
  American Journal of Physical Anthropology. January 24, 2017
  Objectives To describe the strategy employed by exudativorous primates during seasonal shifts in food abundance using the Javan slow loris as a model. Males and females may cope differently as well as exploit fallback foods in different proportions. Materials and methods Observing 15 free ranging Javan slow lorises over a year, we quantified their seasonal diet and nutrient intake using intake rates. For gum intake rates, we conducted a trial with 10 captive Javan slow lorises measuring the length of time it took for them to ingest 10 g of gum. We monitored phenology in our field site over five plots that were assessed monthly. We weighed our free‐ranging animals every six months. We analyzed all food items slow lorises ingested for macronutrients using the nutritional geometry framework. Results The slow loris diet consisted of eight food categories, with gum and insects being the major food sources in terms of wet weight intake. The captive gum trials resulted in an intake rate of 0.021 g/s. All food items eaten by wild Javan slow lorises were available in the wet season and were restricted in the dry season. Males and females reacted differently to seasonal abundances with females ingesting more protein, gum, fruits and flowers and males ingesting more fiber. Conclusions The strategy used by the Javan slow lorises during periods of lower food availability were similar to folivorous primates and included increased dependence on lower quality foods. The reproductive costs of gestation and lactation may place a burden on females that requires them to alter their foraging strategy during the dry season to ensure enough protein and overall energy is ingested. The overall strategy used by these exudativorous primates is one of nutrient maximization as no nutrient was clearly preferred over another.

  January 24, 2017   doi: 10.1002/ajpa.23168   open full text
• A mandible from the Middle Pleistocene Hexian site and its significance in relation to the variability of Asian Homo erectus.
  Wu Liu, María Martinón‐Torres, Yousuke Kaifu, Xiujie Wu, Reiko T. Kono, Chun‐Hsiang Chang, Pianpian Wei, Song Xing, Wanbo Huang, José María Bermúdez de Castro.
  American Journal of Physical Anthropology. January 21, 2017
  Objectives This study presents the first detailed morphological description and comparison of a Middle Pleistocene hominin mandibular fragment (PA 831) and associated teeth from the Hexian site in Eastern China. We aim to investigate where the Hexian mandible fits within the genus Homo variability in the light of an increased and better characterized Asian fossils record. Methods Comparative samples include Pleistocene Homo mandibles and teeth from Africa, Asia, and Europe, as well as earlier African hominins (Australopithecus and early Homo) and Holocene recent humans. Both conventional morphological description and metric analysis were used. In addition, virtual reconstructions of the enamel dentine junction (EDJ) surface, pulp cavity, and roots with micro‐CT were used to the mandible and teeth. Results The Hexian mandible is characterized by a plesiomorphic structural pattern for the Homo clade, with strong corpus robustness and a subparallel and low‐positioned mylohyoid line that differentiates the swollen subalveolar planum from the shallow subalveolar fossa. Features that are derived compared to early Homo include a moderately curved dental arcade, a well‐developed lateral prominence placed at the M2‐M3 level, and multiple mental foramina. The Hexian mandible's complex enamel surface and strong, stout root structure are primitive traits for the Homo clade. Finally, the highly crenulated “dendrite‐like” EDJ found in the molars may represent a dental feature specific to the continental Asian Homo erectus, but more data is needed to confirm this. Conclusions Mandibular and dental features indicate that the Hexian mandible and teeth differ from northern Chinese H. erectus and European Middle Pleistocene hominins, but show some affinities with the Early Pleistocene specimens from Africa (Homo ergaster) and Java (H. erectus), as well as the Middle‐Late Pleistocene mandible from Penghu, Taiwan. Compared to contemporaneous continental Asian hominin populations, the Hexian fossils may represent the survival of a primitive hominin, with more primitive morphologies than other contemporaneous or some chronologically older Asian hominin specimens.

  January 21, 2017   doi: 10.1002/ajpa.23162   open full text
• Domestication and human demographic history in South America.
  S. Ivan Perez, María Bárbara Postillone, Diego Rindel.
  American Journal of Physical Anthropology. January 21, 2017
  Objectives The early groups of hunter‐gatherers who peopled South America faced significant ecological changes in their trophic niche for a relatively short period after the initial peopling. In particular, the incorporation of cultigens during the Holocene led to a wider trophic niche and probably to an increased carrying capacity of the environment. Here, we study the relationship between the incorporation of domestic resources during the Holocene and the demographic dynamics of human populations at a regional scale in South America. Material and methods We employ mitochondrial DNA (mtDNA), radiocarbon data and Bayesian methods to estimate differences in population size, human occupation and explore the demographic changes of human populations in three regions (i.e., South‐Central Andes, Northwest, and South Patagonia). We also use archaeological evidence to infer the main diet changes in these regions. Results The absolute population size during the later Late Holocene was fifteen times larger in the South‐Central Andes than in Northwest Patagonia, and two times larger in the latter region than in South Patagonia. The South‐Central Andes display the earlier and more abrupt population growth, beginning about 9000 years BP, whereas Northwest Patagonia exhibits a more slow growth, beginning about 7000–7500 years BP. South Patagonia represents a later and slower population increase. Discussion In this work we uncovered a well‐supported pattern of the demographic change in the populations from South‐Central Andes and Patagonia, obtained on the basis of different data and quantitative approaches, which suggests that the incorporation of domestic resources was paramount for the demographic expansion of these populations during the Holocene.

  January 21, 2017   doi: 10.1002/ajpa.23176   open full text
• Early medieval stone‐lined graves in Southern Germany: analysis of an emerging noble class.
  Andreas Rott, Nils Turner, Ulrike Scholz, Kristin von Heyking, Franziska Immler, Joris Peters, Jochen Haberstroh, Michaela Harbeck.
  American Journal of Physical Anthropology. January 19, 2017
  Objectives Stone‐lined graves, which first appear in Bavarian territory during the 7th century AD, are assumed to be tombs of emerging nobility. While previous research on stone‐lined grave goods supports their status as elite burials, an important factor defining nobility—kinship—has not been examined so far. Materials and methods Morphological analysis of the commingled skeletal remains of 21 individuals from three archaeological sites was carried out. Radiocarbon dating was conducted on these individuals to gain information on usage intervals of these graves. To test whether stone‐lined graves can be considered family graves, analyses of mitochondrial HVR I, Y‐chromosomal and autosomal STRs were carried out. Results Morphological examination revealed a surplus of males buried in stone‐lined graves and radiocarbon dating points to usage of the tombs for several generations. According to aDNA analysis, kinship can be assumed both between and within stone‐lined graves. Discussion Taken together, these results hint at burials of family members with high social status being inhumed at the same site, in some cases even the same grave, for several generations. They also suggest, for the first time, that an early medieval linear cemetery was structured according to biological kinship.

  January 19, 2017   doi: 10.1002/ajpa.23170   open full text
• Low trabecular bone density in recent sedentary modern humans.
  Habiba Chirchir, Christopher B. Ruff, Juho‐Antti Junno, Richard Potts.
  American Journal of Physical Anthropology. January 19, 2017
  Objectives Research on a limited number of samples suggests that trabecular bone density (i.e., bone volume fraction, BVF) within specific articulations is lower among more sedentary Holocene agricultural populations compared with Holocene foragers, implying that activity levels have a significant effect on trabecular BVF. However, it is unclear to what extent BVF differs among groups with varying activity levels and how general this phenomenon is across multiple limb articulations. Here, we test two hypotheses that: (i) sedentary populations have lower BVF compared with active populations across limb articulations; and (ii) these declines are more uniform in the lower limb (because of its more direct relationship to mobility), and more variable in the upper limb. Materials and Methods We estimated BVF in seven lower and upper limb articulations of five Holocene population samples with subsistence strategies spanning from foraging through horticultural to industrial using pQCT (peripheral Quantitative Computed Tomography). Results Both hypotheses are largely supported. First, the most active groups have significantly greater BVF in most limb elements compared with more sedentary groups. Second, all sedentary groups have relatively similar (and lower) BVF in the lower limb but show more variation in upper limb articulations. Conclusions These results suggest that a decline in activity levels associated with the adoption of agriculture and industrialization significantly contributed to the reduction in BVF in recent modern humans, but specific behavioral changes, particularly in the upper limb, also affected these patterns.

  January 19, 2017   doi: 10.1002/ajpa.23138   open full text
• Biomechanical implications of walking with indigenous footwear.
  Catherine Willems, Gaetane Stassijns, Wim Cornelis, Kristiaan D'Août.
  American Journal of Physical Anthropology. January 19, 2017
  Objectives This study investigates biomechanical implications of walking with indigenous “Kolhapuri” footwear compared to barefoot walking among a population of South Indians. Materials and methods Ten healthy adults from South India walked barefoot and indigenously shod at voluntary speed on an artificial substrate. The experiment was repeated outside, on a natural substrate. Data were collected from (1) a heel‐mounted 3D‐accelerometer recording peak impact at heel contact, (2) an ankle‐mounted 3D‐goniometer (plantar/dorsiflexion and inversion/eversion), and (3) sEMG electrodes at the m. tibialis anterior and the m. gastrocnemius medialis. Results Data show that the effect of indigenous footwear on the measured variables, compared to barefoot walking, is relatively small and consistent between substrates (even though subjects walked faster on the natural substrate). Walking barefoot, compared to shod walking yields higher impact accelerations, but the differences are small and only significant for the artificial substrate. The main rotations of the ankle joint are mostly similar between conditions. Only the shod condition shows a faster ankle rotation over the rapid eversion motion on the natural substrate. Maximal dorsiflexion in late stance differs between the footwear conditions on an artificial substrate, with the shod condition involving a less dorsiflexed ankle, and the plantar flexion at toe‐off is more extreme when shod. Overall the activity pattern of the external foot muscles is similar. Discussion The indigenous footwear studied (Kolhapuri) seems to alter foot biomechanics only in a subtle way. While offering some degree of protection, walking in this type of footwear resembles barefoot gait and this type of indigenous footwear might be considered “minimal”.

  January 19, 2017   doi: 10.1002/ajpa.23169   open full text
• Does cortical bone thickness in the last sacral vertebra differ among tail types in primates?
  Abigail C. Nishimura, Gabrielle A. Russo.
  American Journal of Physical Anthropology. January 11, 2017
  Objectives The external morphology of the sacrum is demonstrably informative regarding tail type (i.e., tail presence/absence, length, and prehensility) in living and extinct primates. However, little research has focused on the relationship between tail type and internal sacral morphology, a potentially important source of functional information when fossil sacra are incomplete. Here, we determine if cortical bone cross‐sectional thickness of the last sacral vertebral body differs among tail types in extant primates and can be used to reconstruct tail types in extinct primates. Materials and Methods Cortical bone cross‐sectional thickness in the last sacral vertebral body was measured from high‐resolution CT scans belonging to 20 extant primate species (N = 72) assigned to tail type categories (“tailless,” “nonprehensile short‐tailed,” “nonprehensile long‐tailed,” and “prehensile‐tailed”). The extant dataset was then used to reconstruct the tail types for four extinct primate species. Results Tailless primates had significantly thinner cortical bone than tail‐bearing primates. Nonprehensile short‐tailed primates had significantly thinner cortical bone than nonprehensile long‐tailed primates. Cortical bone cross‐sectional thickness did not distinguish between prehensile‐tailed and nonprehensile long‐tailed taxa. Results are strongly influenced by phylogeny. Corroborating previous studies, Epipliopithecus vindobonensis was reconstructed as tailless, Archaeolemur edwardsi as long‐tailed, Megaladapis grandidieri as nonprehensile short‐tailed, and Palaeopropithecus kelyus as nonprehensile short‐tailed or tailless. Conclusions Results indicate that, in the context of phylogenetic clade, measures of cortical bone cross‐sectional thickness can be used to allocate extinct primate species to tail type categories.

  January 11, 2017   doi: 10.1002/ajpa.23167   open full text
• Quantitative genetic analysis of the body composition and blood pressure association in two ethnically diverse populations.
  Sudipta Ghosh, Tasbulat Dosaev, Jai Prakash, Gregory Livshits.
  American Journal of Physical Anthropology. January 07, 2017
  Objectives The major aim of this study was to conduct comparative quantitative‐genetic analysis of the body composition (BCP) and somatotype (STP) variation, as well as their correlations with blood pressure (BP) in two ethnically, culturally and geographically different populations: Santhal, indigenous ethnic group from India and Chuvash, indigenous population from Russia. Materials and Methods Correspondently two pedigree‐based samples were collected from 1,262 Santhal and1,558 Chuvash individuals, respectively. At the first stage of the study, descriptive statistics and a series of univariate regression analyses were calculated. Finally, multiple and multivariate regression (MMR) analyses, with BP measurements as dependent variables and age, sex, BCP and STP as independent variables were carried out in each sample separately. The significant and independent covariates of BP were identified and used for re‐examination in pedigree‐based variance decomposition analysis. Results and Discussion Despite clear and significant differences between the populations in BCP/STP, both Santhal and Chuvash were found to be predominantly mesomorphic irrespective of their sex. According to MMR analyses variation of BP significantly depended on age and mesomorphic component in both samples, and in addition on sex, ectomorphy and fat mass index in Santhal and on fat free mass index in Chuvash samples, respectively. Additive genetic component contributes to a substantial proportion of blood pressure and body composition variance. Variance component analysis in addition to above mentioned results suggests that additive genetic factors influence BP and BCP/STP associations significantly.

  January 07, 2017   doi: 10.1002/ajpa.23161   open full text
• Hadza sleep biology: Evidence for flexible sleep‐wake patterns in hunter‐gatherers.
  David R. Samson, Alyssa N. Crittenden, Ibrahim A. Mabulla, Audax Z.P. Mabulla, Charles L. Nunn.
  American Journal of Physical Anthropology. January 07, 2017
  Objectives Cross‐cultural sleep research is critical to deciphering whether modern sleep expression is the product of recent selective pressures, or an example of evolutionary mismatch to ancestral sleep ecology. We worked with the Hadza, an equatorial, hunter‐gatherer community in Tanzania, to better understand ancestral sleep patterns and to test hypotheses related to sleep segmentation. Methods We used actigraphy to analyze sleep‐wake patterns in thirty‐three volunteers for a total of 393 days. Linear mixed effects modeling was performed to assess ecological predictors of sleep duration and quality. Additionally, functional linear modeling (FLM) was used to characterize 24‐hr time averaged circadian patterns. Results Compared with post‐industrialized western populations, the Hadza were characterized by shorter (6.25 hr), poorer quality sleep (sleep efficiency = 68.9%), yet had stronger circadian rhythms. Sleep duration time was negatively influenced by greater activity, age, light (lux) exposure, and moon phase, and positively influenced by increased day length and mean nighttime temperature. The average daily nap ratio (i.e., the proportion of days where a nap was present) was 0.54 (SE = 0.05), with an average nap duration of 47.5 min (SE = 2.71; n = 139). Discussion This study showed that circadian rhythms in small‐scale foraging populations are more entrained to their ecological environments than Western populations. Additionally, Hadza sleep is characterized as flexible, with a consistent early morning sleep period yet reliance upon opportunistic daytime napping. We propose that plasticity in sleep‐wake patterns has been a target of natural selection in human evolution.

  January 07, 2017   doi: 10.1002/ajpa.23160   open full text
• Morphological integration of the cranium in Homo, Pan, and Hylobates and the evolution of hominoid facial structures.
  Dimitri Neaux.
  American Journal of Physical Anthropology. December 30, 2016
  Objectives Modern humans diverge from other extant hominids (chimpanzees, gorillas, and orangutans) in a series of craniofacial morphological features. Like hylobatids, they possess a face with a reduced subnasal prognathism that is associated with a globular basicranium. These traits are not independent, as the skull is a complex integrated structure. The aim of the present study is to determine relationships between the face and the basicranium in two hominid genera (Homo and Pan) and a hylobatid genus (Hylobates) to test if these taxa share common patterns of integration linking these structures. Materials and Methods Three dimensional (3D) geometric morphometric analyses and 3D homologous landmarks are used to compare the integration patterns between facial and basicranial structures in a comparative sample of Homo, Pan, and Hylobates. Pooled within‐genus partial least squares analyses are computed to describe and quantify these patterns of integration. Results The covariation analyses show similar patterns of integration shared between the three studied taxa. These patterns correspond to the brachycephalic and dolichocephalic conditions previously defined in hominins and hominids. Discussion Results confirm that hominoids share similar patterns of integration. This is in line with the hypothesis that morphological integration is mostly conservative in hominoids. These similar patterns of integration may explain the convergent evolution of short faces in humans and hylobatids.

  December 30, 2016   doi: 10.1002/ajpa.23163   open full text
• Evidence of toothpick groove formation in Neandertal anterior and posterior teeth.
  Almudena Estalrrich, José Antonio Alarcón, Antonio Rosas.
  American Journal of Physical Anthropology. December 30, 2016
  Objectives During the microscopic examination of the Neandertal dentitions from El Sidrón (Spain) and Hortus (France), we found unusual fine parallel microstriations on the mesial and distal sides of all tooth types, near the cervix. As its appearance was similar to toothpick grooves described in other Homo species, it could correspond to early stages on its formation. To test this hypothesis we developed an experimental replication of a groove using grass stalks. Materials and Methods Comparisons between 204 isolated Neandertal teeth and the two experimental dental specimens corroborate that the marks correspond to initial stages of toothpick groove formation, and we propose a five‐grade recording scale that summarized the groove formation process. Results Using this new recording procedure, we found that Hortus individuals have higher incidence of this trait (eight individuals out of nine) than the El Sidrón individuals (nine out of 11). Toothpick grooves from El Sidrón show the earliest stages of development, whereas the grooves found on Hortus Neandertals were well‐developed. Toothpick grooves were also found in 21 incisors and canines. Conclusions These differences could be due to the more advanced occlusal dental wear in Hortus individuals, maybe age‐related and with a more meat‐based diet maybe favoring the inclusion of food debris and thus probing as the cleaning methodology. Our results allow the identification and characterization of incipient toothpick grooves on the human fossil record and contribute to increase our knowledge on Neandertals behavioral and oral care habits.

  December 30, 2016   doi: 10.1002/ajpa.23166   open full text
• Natural selection and type 2 diabetes‐associated mortality in an isolated indigenous community in the valley of Oaxaca, southern Mexico.
  Bertis B. Little, Maria Eugenia Peña Reyes, Robert M. Malina.
  American Journal of Physical Anthropology. December 23, 2016
  Objective This study tests the hypothesis that natural selection is associated with type 2 diabetes (T2D)‐associated mortality and fertility in a rural isolated Zapotec community in the Valley of Oaxaca, southern Mexico. Participants and Methods Mortality data and related demographic and genealogic information were linked with data for fertility, prereproductive mortality and family history of mortality attributed to T2D. Physician verified T2D mortality (n = 27) between 1980 and 2009 and imputed T2D (n = 70) from cardiovascular mortality (68% random sample) and renal failure (44% random sample). Bootstrapping was used to obtain a robust variance estimate in survival analysis and multivariate analysis of variance. Results Estimated maximum natural selection by Crow's Index occurred circa 1930 and was relaxed after this time in the study population. Cox‐regression survival analysis of T2D mortality with covariates (family history of T2D, cardiovascular disease, renal failure) indicated a significant hazard ratio (HR = 5.95, 95% CI: 1.38–25.67, p < .008) for the increase in T2D in 2000 to 2009. Survival analysis of imputed T2D resulted in a significant HR of 2.03 (95% CI: 1.08–3.85, p = .01) for the increase in T2D in the 2000 to 2009 cohort (reference group: 1980–1989). Mean number of live born offspring was lower among T2D (n = 27, 4.04 ± 3.85 SD) compared to non‐T2D (n = 199, 5.30 ± 3.48) groups (p < .08). Mean number of live born offspring was lower (p = .003) among imputed T2D compared to non‐T2D groups (4.10 ± 3.44 vs. 5.62 + 3.50). Discussion T2D‐associated mortality increased in frequency as natural selection decreased, and favored offspring survival of non‐T2D descedants. The results indicated statistically significant directional selection against T2D and imputed T2D to this population isolate.

  December 23, 2016   doi: 10.1002/ajpa.23139   open full text
• Hyperostosis frontalis interna in female historic skeletal populations: Age, sex hormones and the impact of industrialization.
  A. G. Western, J. J. Bekvalac.
  American Journal of Physical Anthropology. November 30, 2016
  Objectives This analysis aims to investigate the impact of industrialization on the prevalence of Hyperostosis Frontalis Interna (HFI), focusing on the roles of age and parity to examine the claim that longevity and changing reproductive patterns have led to increased rates in modern populations. Materials and methods A total of 138 individuals from two documented London skeletal assemblages of the Industrial period were analyzed employing macroscopic observation, digital radiography and MicroCT scanning to establish the prevalence rates of HFI according to modern clinical standards. Statistical analysis was also undertaken on a sub‐sample of 51 females of post‐menopausal age to identify any relationship between parity and HFI. Results The majority of cases of HFI were found in older females, reflecting clinical observations. The prevalence rates of HFI corresponded well to those predicted from the proportion of old age females present within populations. Age was therefore shown to be a predominant factor in HFI presence. A plateau in HFI prevalence was noted from the age of 50–59 years onwards. No statistically significant relationship was found between parity and HFI. Discussion When recorded consistently, HFI was positively correlated with age and longevity but had also increased among old age females over time. Our results suggest that nulliparity co‐occurs with HFI but is not a primary factor in its pathogenesis. Key factors in HFI presence in females are likely to be increased androgens and the dysregulation of insulin and insulin‐like growth factor‐1.

  November 30, 2016   doi: 10.1002/ajpa.23133   open full text
• Principal component analysis in the evaluation of osteoarthritis.
  Stephanie E. Calce, Helen K. Kurki, Darlene A. Weston, Lisa Gould.
  American Journal of Physical Anthropology. November 29, 2016
  Objectives The purpose of this study is to demonstrate advantages of principal component analysis (PCA) as a standardized procedure in the evaluation of osteoarthritis (OA) in a skeletal series to: (1) compute aggregate scores for joint complexes that accurately capture pathological expression, (2) reveal which variables describe the most sample variation in OA, (3) enable inter‐ and intra‐sample comparison of results, and (4) formulate predictive models from component‐based arthritic scores. Materials and methods The sample (144 males, 145 females) is drawn from a large skeletal cemetery collection of modern Europeans of known sex, age, and occupation. OA data was collected using standard ranked categorical scoring. PCA was conducted separately on lumbar spine, pelvis, and knee regions to generate composite OA scores from eigenequations of the first and second principal components (PC). Results Results demonstrate that as severity in OA increases, so does the distribution of OA within the joint surface. In each region, PCA produced the same general pattern with eburnation scoring driving significant changes in composite OA scores, representing earlier to later stages of cartilage degeneration. The distribution of arthritic traits determined by PCA produced an OA score that quantifies the expression of joint changes in varied biological joint structures from most moveable to least mobile, the final stage being joint fusion. OA scores are most highly variable in the lumbar region for both males and females, as compared to the pelvis and knee. Conclusions PCA is a simple, non‐parametric method of extracting relevant information from complex OA datasets and summarizes variation based on correlated multi‐attributes to reveal a simplified structure of OA expression. Multivariate techniques like PCA should be used to describe discrete OA samples, and are useful to compute population‐specific representative measurements for idiopathic joint OA in a skeletal sample.

  November 29, 2016   doi: 10.1002/ajpa.23130   open full text
• Structural organization and tooth development in a Homo aff. erectus juvenile mandible from the Early Pleistocene site of Garba IV at Melka Kunture, Ethiopian highlands.
  Clément Zanolli, M. Christopher Dean, Yared Assefa, Priscilla Bayle, José Braga, Silvana Condemi, Metasebia Endalamaw, Blade Engda Redae, Roberto Macchiarelli.
  American Journal of Physical Anthropology. November 24, 2016
  Objectives The immature partial mandible GAR IVE from the c. 1.7 Ma old Garba IV site at Melka Kunture (Upper Awash Basin, Ethiopia), the earliest human representative from a mountain‐like environment, represents one of the oldest early Homo specimens bearing a mixed dentition. Following its first description (Condemi, ), we extended the analytical and comparative record of this specimen by providing unreported details about its inner morphology, tooth maturational pattern and age at death, crown size, and tooth tissue proportions. Materials and Methods The new body of quantitative structural information and virtual imaging derives from a medical CT record performed in 2013. Results Compared to the extant human condition and to some fossil representatives of comparable individual age, the GAR IVE mandible reveals absolutely and relatively thick cortical bone. Crown size of the permanent lateral incisor and the canine fit the estimates of H. erectus s.l., while the dm2 and the M1 more closely approach those of H. habilis‐rudolfensis. Molar crown pulp volumes are lower than reported in other fossil specimens and in extant humans. The mineralization sequence of the permanent tooth elements is represented four times in our reference sample of extant immature individuals (N = 795). Conclusions The tooth developmental pattern displayed by the immature individual from Garba IV falls within the range of variation of extant human populations and is also comparable with that of other very young early fossil hominins. Taken together, the evidence presented here for mandibular morphology and dental development suggest GAR IVE is a robust 2.5‐ to 3.5‐year old early Homo specimen.

  November 24, 2016   doi: 10.1002/ajpa.23135   open full text
• Anthropologists' views on race, ancestry, and genetics.
  Jennifer K. Wagner, Joon‐Ho Yu, Jayne O. Ifekwunigwe, Tanya M. Harrell, Michael J. Bamshad, Charmaine D. Royal.
  American Journal of Physical Anthropology. November 22, 2016
  Controversies over race conceptualizations have been ongoing for centuries and have been shaped, in part, by anthropologists. Objective To assess anthropologists' views on race, genetics, and ancestry. Methods In 2012 a broad national survey of anthropologists examined prevailing views on race, ancestry, and genetics. Results Results demonstrate consensus that there are no human biological races and recognition that race exists as lived social experiences that can have important effects on health. Discussion Racial privilege affects anthropologists' views on race, underscoring the importance that anthropologists be vigilant of biases in the profession and practice. Anthropologists must mitigate racial biases in society wherever they might be lurking and quash any sociopolitical attempts to normalize or promote racist rhetoric, sentiment, and behavior.

  November 22, 2016   doi: 10.1002/ajpa.23120   open full text
• Spatial variation in mandibular bone elastic modulus and its effect on structural bending stiffness: A test case using the Taï Forest monkeys.
  Kim N. Le, Matthew Marsik, David J. Daegling, Ana Duque, William Scott McGraw.
  American Journal of Physical Anthropology. November 18, 2016
  Objectives We investigated how heterogeneity in material stiffness affects structural stiffness in the cercopithecid mandibular cortical bone. We assessed (1) whether this effect changes the interpretation of interspecific structural stiffness variation across four primate species, (2) whether the heterogeneity is random, and (3) whether heterogeneity mitigates bending stress in the jaw associated with food processing. Materials and methods The sample consisted of Taï Forest, Cote d'Ivoire, monkeys: Cercocebus atys, Piliocolobus badius, Colobus polykomos, and Cercopithecus diana. Vickers indentation hardness samples estimated elastic moduli throughout the cortical bone area of each coronal section of postcanine corpus. For each section, we calculated maximum area moment of inertia, Imax (structural mechanical property), under three models of material heterogeneity, as well as spatial autocorrelation statistics (Moran's I, IMORAN). Results When the model considered material stiffness variation and spatial patterning, Imax decreased and individual ranks based on structural stiffness changed. Rank changes were not significant across models. All specimens showed positive (nonrandom) spatial autocorrelation. Differences in IMORAN were not significant among species, and there were no discernable patterns of autocorrelation within species. Across species, significant local IMORAN was often attributed to proximity of low moduli in the alveolar process and high moduli in the basal process. Discussion While our sample did not demonstrate species differences in the degree of spatial autocorrelation of elastic moduli, there may be mechanical effects of heterogeneity (relative strength and rigidity) that do distinguish at the species or subfamilial level (i.e., colobines vs. cercopithecines). The potential connections of heterogeneity to diet and/or taxonomy remain to be discovered.

  November 18, 2016   doi: 10.1002/ajpa.23134   open full text
• A multi‐isotope investigation of diet and subsistence amongst island and mainland populations from early medieval western Britain.
  Katie A. Hemer, Angela L. Lamb, Carolyn A. Chenery, Jane A. Evans.
  American Journal of Physical Anthropology. November 17, 2016
  Objectives This is the first investigation of dietary practices amongst multiple early medieval populations (AD 500–1000) from Wales and the Isle of Man using carbon, nitrogen, and sulphur isotope analysis. The analysis will illuminate similarities or differences between the diets and subsistence strategies of populations occupying different geographical regions, specifically those living in marginal coastal regions in comparison to inland populations well‐connected to ecclesiastical centres and high‐status settlements. Materials and Methods One hundred and two human skeletons were sampled for carbon and nitrogen isotope analysis, and 69 human skeletons were sampled for sulphur isotope analysis from nine cemetery sites from western Britain (Isle of Man = 3, southwest Wales = 4, southeast Wales = 2). Thirteen faunal skeletons from St Patrick's Chapel (southwest Wales) were sampled for carbon, nitrogen, and sulphur isotope analysis. Results Human δ13C values range from −19.4‰ to −21.2‰ (δ13C mean=−20.4 ±0.4‰, 1σ, n = 86), and δ15N values range from 9.1‰ to 13.8‰ (δ15N mean = 10.8 ± 0.9‰, 1σ, n = 86). δ34S values range from 1.2‰ to 18.4‰ (δ34S mean = 11.6 ± 4.5‰, 1σ, n = 66). Significant differences were noted between the mean δ13C, δ15N and δ34S values according to geographic region: Isle of Man (δ13C = −20.7 ± 0.4‰, δ15N = 11.4 ±0.6‰, n = 13/86; δ34S mean = 17.1 ±0.6, n = 4/66), southwest Wales (δ13C = −20.5 ± 0.4‰, δ15N = 11.0 ±1‰, n = 32/86; δ34S = 16.1 ± 2.1, n = 21/66), and southeast Wales (δ13C =−20.3 ±0.4‰, δ15N = 10.4 ±0.7‰, n = 41/86; δ34S= 8.8 ±3‰, n = 41/66). Faunal δ13C values range from −23.1‰ to −21.2‰ (δ13C mean= −22.1 ±0.5‰, 1σ, n = 13), and δ15N values range from 6.3‰ to 9.8‰ (δ15N mean = 7.3 ± 1.1‰, 1σ, n = 13). δ34S values range from 4.7‰ to 18.4‰ (δ34S mean= 16.3 ± 3.6‰, 1σ, n = 13). Conclusions The data reveal a reliance on terrestrial protein, however differences are observed between the resource consumption of populations from southwest Wales and the Isle of Man in comparison to the populations from southeast Wales. Populations from the west coast have a marine sulphur signature that reflects their coastal proximity and may also include a reliance on seaweed as a fertiliser/food source. Populations in the southeast were connected to ecclesiastical centres and high‐status settlements and had access to inland‐grown produce. The data add support to the suggestion that δ34S can be used as a mobility indicator.

  November 17, 2016   doi: 10.1002/ajpa.23127   open full text
• Copper and zinc isotope ratios in human bone and enamel.
  Klervia Jaouen, Estelle Herrscher, Vincent Balter.
  American Journal of Physical Anthropology. November 17, 2016
  Objectives Here, we report Cu and Zn isotope ratios of bones and teeth of French people from various historical periods with the aim to understand how Cu and Zn isotope ratios of bone, a tissue that is continuously remodeled throughout life but that is prone to post‐mortem diagenesis, compare with that of tooth enamel, a tissue that forms once during childhood but that is more resistant to diagenesis. Specifically, we examine (1) the potential existence of sex‐related differences in the Cu isotope ratios (represented as δ65Cu) in the tooth enamel of identified men and women, and (2) a decrease of Zn isotope delta ratios (represented as δ66Zn) related to the increase of meat and fish consumption during the 20th century. Methods Four series of material were studied: the archeological population of Saint‐Laurent de Grenoble (17th–18th centuries AD), an anatomical collection of skulls (19th century AD), a contemporary anatomical collection of bones never buried, and contemporary teeth samples. The metals were purified by liquid chromatography and their isotopic ratios measured by means of multicollector inductively coupled plasma mass spectrometry. Results We describe a clear offset between bone and tooth enamel for Zn isotope ratios, as previously observed in animals. There is a similar offset for Cu isotope ratios. We did not observe any difference between the δ65Cu values of men and women when looking at dental enamel. For the contemporary samples, the δ66Zn values of bioapatite decreased, which might be explained by the increase of animal product consumption among the French people during this period, notably when the access to seafood became widespread. Conclusions Our study demonstrates that the Cu and Zn isotope compositions of dental enamel are promising tools for childhood diet reconstruction. Meanwhile, the Cu isotope ratio of tooth enamel is unlikely to be useful for the identification of biological sex, even in the case of populations with early menarche. Further works are needed to understand the relationships between trophic level and Zn isotope ratios of human remains.

  November 17, 2016   doi: 10.1002/ajpa.23132   open full text
• Dietary habits in New France during the 17th and 18th centuries: An isotopic perspective.
  J. Vigeant, I. Ribot, J.‐F. Hélie.
  American Journal of Physical Anthropology. November 11, 2016
  Objective Little attention has been given, so far, to the early colonial diet in New France from an isotopic perspective. Historical records that compare France to New France suggest a shift toward a more diverse diet, including a higher protein intake due to an improvement in living conditions in the New World, despite the retention of ancestral dietary habits. This hypothesis will be explored here. Materials and methods Stable carbon (organic and mineral) and nitrogen isotopes were measured on 43 individuals from Notre Dame cemetery (first Catholic parish church cemetery in Montreal, 1683–1803) as well as 13 French compatriots from La Rochelle, France (Protestant Hospital Cemetery, 1765–1792). Intragroup variation (age at death, sex, and/or burial location) was investigated and compared to compiled data from various northeastern North American sites (N = 99). Results The Notre Dame sample means are as follows: −19.6‰ versus VPDB for δ13Ccollagen, −12.22‰ versus VPDB for δ13Ccarbonate, and 11.5‰ versus AIR for δ15N. They are significantly lower than both La Rochelle (−18.4‰, −11.67‰, and 12.7‰, respectively, p ≤ .005) and the northeastern North American groups used for this comparison (p = .000). Discussion The isotopic values obtained from Notre Dame cemetery suggest that the diet was mainly based on C3 resources with limited C4 resources. Although different from all comparable contemporary sites, colonial Montreal's diet remains most similar to La Rochelle, France. This study agrees with historians who have suggested that French dietary traditions seem to have been retained among the early colonial inhabitants of Montreal.

  November 11, 2016   doi: 10.1002/ajpa.23129   open full text
• Growth references for Tsimane forager‐horticulturalists of the Bolivian Amazon.
  Aaron D. Blackwell, Samuel S. Urlacher, Bret Beheim, Christopher von Rueden, Adrian Jaeggi, Jonathan Stieglitz, Benjamin C. Trumble, Michael Gurven, Hillard Kaplan.
  American Journal of Physical Anthropology. November 07, 2016
  Objectives Growth standards and references currently used to assess population and individual health are derived primarily from urban populations, including few individuals from indigenous or subsistence groups. Given environmental and genetic differences, growth may vary in these populations. Thus, there is a need to assess whether international standards are appropriate for all populations, and to produce population specific references if growth differs. Here we present and assess growth references for the Tsimane, an indigenous population of Bolivian forager‐horticulturalists. Methods Mixed cross‐sectional/longitudinal anthropometrics (9,614 individuals; 30,118 observations; ages 0–29 years) were used to generate centile curves and Lambda‐Mu‐Sigma (LMS) tables for height‐for‐age, weight‐for‐age, body mass index (BMI)‐for‐age, and weight‐for‐height (WFH) using Generalized Additive Models for Location Shape and Scale (GAMLSS). Velocity curves were generated using SuperImposition by Translation and Rotation (SITAR). Tsimane ≤5 years were compared to World Health Organization (WHO) standards while those >5 years were compared to WHO school age references. All ages were compared to published references for Shuar forager‐horticulturalists of the Ecuadorian Amazon. Results Tsimane growth differs from WHO values in height and weight, but is similar for BMI and WFH. Tsimane growth is characterized by slow height velocity in childhood and early adolescent peak height velocity at 11.3 and 13.2 years for girls and boys. Tsimane growth patterns are similar to Shuar, suggesting shared features of growth among indigenous South Americans. Conclusions International references for BMI‐for‐age and WFH are likely appropriate for Tsimane, but differences in height‐for‐age and weight‐for‐age suggest Tsimane specific references may be useful for these measures.

  November 07, 2016   doi: 10.1002/ajpa.23128   open full text
• Energy‐related influences on variation in breastfeeding duration among indigenous Maya women from Guatemala.
  Luseadra J. McKerracher, Mark Collard, Rachel M. Altman, Daniel Sellen, Pablo A. Nepomnaschy.
  American Journal of Physical Anthropology. November 03, 2016
  Objectives The causes of variation in breastfeeding duration in humans are poorly understood, but life history factors related to maternal energetics drive much of the variation in lactation duration in nonhuman animals. With this in mind, we investigated whether four energy‐related factors influence variation in breastfeeding duration in a non‐industrial human population: (1) mortality risk during mother's development (assessed via mother's adult height), (2) reliance on nutrient‐dense weaning foods, (3) access to and need for help with infant feeding and care (“allomaternal care”), and (4) maternal tradeoffs between current and future reproduction (measured via child's birth order). Materials and methods The data pertain to 51 Kakchiquel‐speaking Maya mothers and 283 children from a village in rural Guatemala. We developed a linear mixed model to evaluate the relationships between breastfeeding duration and the energy‐related factors. Results Duration of breastfeeding was associated with two of the energy‐related factors in the ways we predicted but not with the other two. Contrary to predictions, taller mothers breastfed for shorter periods and we found no evidence that weanling diet quality impacts breastfeeding duration. As predicted, women who had more help with infants breastfed for shorter periods, and later‐born infants breastfed longer than earlier‐born ones. Discussion The results regarding allomaternal care suggest that help reduces mothers' lactation demands. The energy saved may be redirected to increasing fecundity or investment in other children. The birth order result suggests that children born to mothers nearing reproductive senescence receive higher levels of investment, which likely impacts children's fitness.

  November 03, 2016   doi: 10.1002/ajpa.23125   open full text
• Humeral correlates of forelimb elevation in four West African cercopithecid monkeys.
  Noah T. Dunham, Erin E. Kane, W. Scott McGraw.
  American Journal of Physical Anthropology. November 02, 2016
  Objectives We previously found that differing degrees of forelimb flexion, elevation, and abduction during nonlocomotor foraging activities covaried with scapular morphology among four sympatric cercopithecids. The purpose of this study is to investigate whether features of the proximal humerus are similarly related to forelimb elevation during foraging. Methods Our sample consists of humeri (n = 42) of adult Cercocebus atys, Cercopithecus diana, Colobus polykomos, and Piliocolobus badius collected from Côte d'Ivoire's Taï National Park. Features of the proximal humerus known to correspond with varying degrees of forelimb mobility were examined using a combination of 2‐dimensional caliper‐based indices and 3‐dimensional analyses. Results Some features of the proximal humerus are consistent with the varying frequencies of forelimb elevation during foraging. For instance, the red colobus (P. badius) has a variety of features consistent with more pronounced shoulder mobility and forelimb flexibility including a wider, more distally projecting deltoid plane, greater tuberosity positioned below the humeral head articular surface, and larger intertuberosity angle. Conclusions The colobines, particularly P. badius, display a number of humeral and scapular features indicative of greater arm flexion, elevation, and abduction compared to the two cercopithecines. We conclude that idiosyncrasies in forelimb use during foraging are reflected in functionally relevant features of the cercopithecid proximal humerus, highlighting that postural behavior, in additional to locomotor behavior, can exert selective pressures on primate skeletal form. This result should provide for more informed reconstructions of the full positional repertoires in fossil taxa.

  November 02, 2016   doi: 10.1002/ajpa.23123   open full text
• Holocene population history of the Sabana de Bogotá region, Northern South America: An assessment of the craniofacial shape variation.
  Miguel Delgado.
  American Journal of Physical Anthropology. October 31, 2016
  Objectives Several authors using multiple and independent lines of evidence investigating the biocultural continuity versus discontinuity in the Sabana de Bogotá region, in the eastern highlands of Colombia, have arrived at contradictory conclusions supporting either scenarios. This study analyzes the craniofacial size and shape variation of diachronic samples from the study region to test distinct population history scenarios that support continuity or, alternatively, divergence. Materials and methods A total of 92 adult skulls belonging to five chronological groups, ranging from c. 10,100 to 350 14C YBP, were analyzed through Procrustean geometric morphometric techniques. Matrix correlation analysis, multivariate exploratory (PCA, FDA), and evolutionary quantitative genetic methods (R‐matrix analysis and β‐test) were used to study the diachronic craniofacial shape variation. Results A model that supports strong evolutionary diversification over the Holocene better explains the patterns of morphological variation observed. At least two periods of significant craniofacial size and shape change were detected: one during the middle to initial late Holocene transition (c. 4,000–3,200 14C YBP) and other toward the final late Holocene (post‐2,000 14C YBP), which exhibit differences in the pattern and magnitude of cranial divergence. In addition, the differentiation viewed between early and mid‐Holocene foragers could mark the initial entry of non‐local populations into the region toward the beginnings of the middle Holocene. Discussion Distinct to previous investigations the present study supports a more complex regional population history where multiple population contractions/extinctions, dispersals and assimilations along with dietary adaptations took place during the last 10,000 years. These results are in agreement with the archaeological and paleoecological record which suggests marked periods of change rather than temporal stability.

  October 31, 2016   doi: 10.1002/ajpa.23124   open full text
• Weaning practices among pastoralists: New evidence of infant feeding patterns from Bronze Age Eurasia.
  Alicia Ventresca Miller, Bryan K. Hanks, Margaret Judd, Andrey Epimakhov, Dmitry Razhev.
  American Journal of Physical Anthropology. October 31, 2016
  Objectives This paper investigates infant feeding practices through stable carbon (δ13C) and nitrogen (δ15N) isotopic analyses of human bone collagen from Kamennyi Ambar 5, a Middle Bronze Age cemetery located in central Eurasia. The results presented are unique for the time period and region, as few cemeteries have been excavated to reveal a demographic cross‐section of the population. Studies of weaning among pastoral societies are infrequent and this research adds to our knowledge of the timing, potential supplementary foods, and cessation of breastfeeding practices. Materials and methods Samples were collected from 41 subadults (<15 years) and 27 adults (15+ years). Isotopic reference sets from adult humans as well as faunal remains were utilized as these form the primary and complementary foods fed to infants. Results Slight shifts in δ13C and δ15N values revealed that weaning was a multi‐stage process (breastfeeding, weaning, and complete cessation of nursing) that began at 6 months of age, occurred over several years of early childhood, and was completed by 4 years of age. Discussion Our results indicate that weaning was a multi‐stage process that was unique among late prehistoric pastoralist groups in Eurasia that were dependent on milk products as a supplementary food. Our discussion centers on supporting this hypothesis with modern information on central and east Eurasian herding societies including the age at which complementary foods are introduced, the types of complementary foods, and the timing of the cessation of breastfeeding. Integral to this work is the nature of pastoral economies and their dependence on animal products, the impact of complementary foods on nutrition and health, and how milk processing may have affected nutrition content and digestibility of foods. This research on Eurasian pastoralists provides insights into the complexities of weaning among prehistoric pastoral societies as well as the potential for different complementary foods to be incorporated into infant diets in the past.

  October 31, 2016   doi: 10.1002/ajpa.23126   open full text
• Investigating economic specialization on the central Peruvian coast: A reconstruction of Late Intermediate Period Ychsma diet using stable isotopes.
  Sara J. Marsteller, Natalya Zolotova, Kelly J. Knudson.
  American Journal of Physical Anthropology. October 25, 2016
  Objectives Hypothetical models of socioeconomic organization in pre‐Columbian societies generated from the rich ethnohistoric record in the New World require testing against the archaeological and bioarchaeological record. Here, we test ethnohistorian Maria Rostworowski's horizontality model of socioeconomic specialization for the Central Andean coast by reconstructing dietary practices in the Late Intermediate Period (c. AD 900‐1470) Ychsma polity to evaluate complexities in social behaviors prior to Inka imperial influence. Materials and methods Stable carbon and nitrogen isotope analysis of archaeological human bone collagen and apatite (δ13Ccol[VPDB], δ15Ncol[AIR], δ13Cap[VPDB]) and locally available foods is used to reconstruct the diets of individuals from Armatambo (n = 67), associated ethnohistorically with fishing, and Rinconada Alta (n = 46), associated ethnohistorically with agriculture. Results Overall, mean δ15Ncol[AIR] is significantly greater at Armatambo, while mean δ13Ccol[VPDB] and mean δ13Cap[VPDB] are not significantly different between the two sites. Within large‐scale trends, adult mean δ13Cap[VPDB] is significantly greater at Armatambo. In addition, nearly one‐third of Armatambo adults and adolescents show divergent δ15Ncol[AIR] values. Discussion These results indicate greater reliance on marine resources at Armatambo versus Rinconada Alta, supporting the ethnohistoric model of socioeconomic specialization for the Central Andean coast. Deviations from large‐scale dietary trends suggest complexities not accounted for by the ethnohistoric model, including intra‐community subsistence specialization and/or variation in resource access.

  October 25, 2016   doi: 10.1002/ajpa.23117   open full text
• Sustained myrmecophagy in Nigerian chimpanzees: Preferred or fallback food?
  Volker Sommer, Umaru Buba, Gonçalo Jesus, Alejandra Pascual‐Garrido.
  American Journal of Physical Anthropology. October 25, 2016
  Objective At some sites across Africa, chimpanzees consume army ants, often aided by plant tools, although consumption frequencies vary greatly. Other populations do not eat these insects at all, despite apparent abundance. The relative importance of this type of myrmecophagy for chimpanzee diet therefore remains unclear. We investigate if army ants constitute a preferred food or a fallback resource for chimpanzees at Gashaka, Nigeria, where army ants are consumed much more frequently than elsewhere. Methods Long‐term records on temporal variation of climate and availability of fruit as the chimpanzees' preferred food are compared with rates of recovered army ant dipping wands and army ant remains in feces. Results Despite strict seasonality of rainfall and fruit abundance, myrmecophagy does not negatively correlate with fruit availability. Instead, army ant eating is sustained year round at high levels, with 44% of feces containing remains. Conclusions Results contradict the fallback hypothesis and support the hypothesis that ants are a preferred food. Nevertheless, compared with fruit, ant‐meals can normally provide only negligible amounts of nutrients. At Gashaka, however, nutritional yield may be significant, given that ant‐dipping sessions provide on average 13 mg of dry weight to a chimpanzee. The species exclusively eaten here, Dorylus rubellus, might be particularly aggressive, thus resulting in greater harvesting success than elsewhere. Army ants may hence serve as a diet supplement or complement in terms of macro‐ or micronutrients.

  October 25, 2016   doi: 10.1002/ajpa.23122   open full text
• A novel fecal stable isotope approach to determine the timing of age‐related feeding transitions in wild infant chimpanzees.
  Iulia Bădescu, M. Anne Katzenberg, David P. Watts, Daniel W. Sellen.
  American Journal of Physical Anthropology. October 21, 2016
  Objectives Determining nutritional development in wild primates is difficult through observations because confirming dietary intake is challenging. Physiological measures are needed to determine the relative contributions of maternal milk and other foods at different ages, and time of weaning. We used fecal stable carbon and nitrogen isotopes (δ13C, δ15N) and fecal nitrogen concentrations (%N) from wild chimpanzees at Ngogo, Uganda, to derive physiological dietary indicators during the transition from total reliance on maternal milk to adult foods after weaning. Materials and Methods We analyzed 560 fecal samples collected non‐invasively from 48 infants, their mothers, and 6 juvenile siblings. Most infant and juvenile samples (90%) were matched to samples collected from mothers on the same day. Isotopic assessments were compared with observations of nursing and feeding. Results Infants ≤1 year old showed average δ15N, δ13C and %N ratios that were 2.0‰, 0.8‰ and 1.3% greater than their mothers, respectively, interpreted as trophic level effects. Although data collected on newborns were few, results suggest that solid foods were consumed within 2–5 months after birth. Trophic level differences decreased steadily after 1 year, which indicates a decreasing relative contribution of milk to the diet. Isotopic results indicated infants were weaned by 4.5 years old—more than a year earlier than observations of nipple contacts ceased, which revealed the occurrence of “comfort nursing.” Juvenile isotopic signatures indicate no nursing overlap between siblings. Discussion Our results resemble the stable isotope differences of human babies. This study contributes to a model of chimpanzee nutritional development required to understand early life history patterns in hominins.

  October 21, 2016   doi: 10.1002/ajpa.23116   open full text
• Quantification of 3D curvature in the iliac crest: Ontogeny and implications for sex determination in juveniles.
  Laura A. B. Wilson, Rachel Ives, Louise T. Humphrey.
  American Journal of Physical Anthropology. October 21, 2016
  Objectives Sex‐specific differences in the shape of the iliac crest have been reported based on quantification of simplified curvature using two‐dimensional variables or qualitative identification of faint/marked S‐shaped curvature. An objective and quantitative approach for the evaluation of iliac crest curvature in juveniles was developed. Using three‐dimensional data, ontogenetic variation in iliac curvature was investigated in relation to size and chronological age and its accuracy for sex estimation among juveniles was evaluated. Materials and Methods Three‐dimensional geometric morphometric landmarks were collected from virtual models of 53 surface‐scanned ilia and used to: (1) quantify differences between male and female shape, and (2) to calculate a measure of sinuosity by extracting linear measurements relative to a plane constructed in virtual space. Results Males were found to exhibit on average more pronounced curvature of the iliac crest than females in equivalent age groups, and the difference between sexes was more marked on the posterior section of the bone than on the anterior section. Classification accuracy was higher for measurements of sinuosity relative to a three‐dimensional plane (62–87%) than for landmarks describing crest shape (64–74%). Conclusions An increased likelihood of correct male identification (reduced rate of false positive identification) was observed in older children (>5 years). This reflects divergence of male and female iliac crest shape with size (or age), and the development of a unique, more curved iliac crest shape in males. The results suggest more conspicuous male trait expression than female trait expression.

  October 21, 2016   doi: 10.1002/ajpa.23114   open full text
• Phylogeny of the jacchus group of Callithrix marmosets based on complete mitochondrial genomes.
  Joanna Malukiewicz, Crystal M. Hepp, Katerina Guschanski, Anne C. Stone.
  American Journal of Physical Anthropology. October 20, 2016
  Objectives Two subgroups make up the marmoset genus Callithrix. The “aurita” group is composed of two species, whereas evolutionary relationships among the four species of the “jacchus” group remain unclear. To uncover these relationships, we first sequenced mitochondrial genomes for C. kuhlii and C. penicillata to complement data available for congeners. We then constructed a phylogenetic tree based on mtDNA heavy chain protein coding genes from several primates to untangle species relationships and estimate divergence times of the jacchus group. Materials and Methods MtDNA genomes of C. kuhlii and C. penicillata were Sanger sequenced. These Callithrix mitogenomes were combined with other publically available primate mtDNA genomes. Phylogenies were produced using maximum likelihood and Bayesian inference. Finally, divergence times within the jacchus group of marmosets were estimated with Bayesian inference. Results In our phylogenetic tree, C. geoffroyi was the sister to all other jacchus group species, followed by C. kuhlii, while C. jacchus and C. penicillata diverged most recently. Bayesian inference showed that C. jacchus and C. penicillata diverged approximately 0.70 MYA and that the jacchus group radiated approximately 1.30 MYA. Discussion Callithrix nuclear and mtDNA phylogenies frequently result in polytomies and paraphyly. Here, we present a well‐supported phylogenetic tree based on mitochondrial genome sequences, which facilitates the understanding of the divergence of the jacchus marmosets. Our results demonstrate how mitochondrial genomes can enrich Callithrix phylogenetic studies by alleviating some of the difficulties faced by previous mtDNA studies and allow formulation of hypotheses to test further under larger genomic‐scale analyses.

  October 20, 2016   doi: 10.1002/ajpa.23105   open full text
• The vanishing Black Indian: Revisiting craniometry and historic collections.
  Pamela L. Geller, Christopher M. Stojanowksi.
  American Journal of Physical Anthropology. October 18, 2016
  Objectives This article uses craniometric allocation as a platform for discussing the legacy of Samuel G. Morton's collection of crania, the process of racialization, and the value of contextualized biohistoric research perspectives in biological anthropology. Materials and Methods Standard craniometric measurements were recorded for seven Seminoles in the Samuel G. Morton Crania Collection and 10 European soldiers from the Fort St. Marks Military Cemetery; all individuals were men and died in Florida during the 19th century. Fordisc 3.1 was used to assess craniometric affinity with respect to three samples: the Forensic Data Bank, Howells data set, and an archival sample that best fits the target populations collected from 19th century Florida. Discriminant function analyses were used to evaluate how allocations change across the three comparative databases, which roughly reflect a temporal sequence. Results Most Seminoles allocated as Native American, while most soldiers allocated as Euro‐American. Allocation of Seminole crania, however, was unstable across analysis runs with more individuals identifying as African Americans when compared to the Howells and Forensic Data Bank. To the contrary, most of the soldiers produced consistent allocations across analyses. Repeatability for the St. Marks sample was lower when using the archival sample database, contrary to expectations. For the Seminole crania, Cohen's κ indicates significantly lower repeatability. A possible Black Seminole individual was identified in the Morton Collection. Discussion Recent articles discussing the merits and weaknesses of comparative craniometry focus on methodological issues. In our biohistoric approach, we use the patterning of craniometric allocations across databases as a platform for discussing social race and its development during the 19th century, a process known as racialization. Here we propose that differences in repeatability for the Seminoles and Euro‐American soldiers reflect this process and transformation of racialized identities during 19th century U.S. nation‐building. In particular, notions of whiteness were and remain tightly controlled, while other racial categorizations were affected by legal, social, and political contexts that resulted in hybridity in lieu of boundedness.

  October 18, 2016   doi: 10.1002/ajpa.23115   open full text
• Paternal and grandpaternal ages at conception and descendant telomere lengths in chimpanzees and humans.
  Dan T. A. Eisenberg, Justin Tackney, Richard M. Cawthon, Christina Theresa Cloutier, Kristen Hawkes.
  American Journal of Physical Anthropology. October 12, 2016
  Telomeres are repeating DNA at chromosome ends. Telomere length (TL) declines with age in most human tissues, and shorter TL is thought to accelerate senescence. In contrast, older men have sperm with longer TL; correspondingly, older paternal age at conception (PAC) predicts longer TL in offspring. This PAC‐effect could be a unique form of transgenerational genetic plasticity that modifies somatic maintenance in response to cues of recent ancestral experience. The PAC‐effect has not been examined in any non‐human mammals. Objectives Here, we examine the PAC‐effect in chimpanzees (Pan troglodytes). The PAC‐effect on TL is thought to be driven by continual production of sperm—the same process that drives increased de novo mutations with PAC. As chimpanzees have both greater sperm production and greater sperm mutation rates with PAC than humans, we predict that the PAC‐effect on TL will be more pronounced in chimpanzees. Additionally we examine whether PAC predicts TL of grandchildren. Materials and methods TL were measured using qPCR from DNA from blood samples from 40 captive chimpanzees and 144 humans. Results Analyses showed increasing TL with PAC in chimpanzees (p = .009) with a slope six times that in humans (p = .026). No associations between TL and grandpaternal ages were found in humans or chimpanzees—although statistical power was low. Discussion These results suggest that sperm production rates across species may be a determinant of the PAC‐effect on offspring TL. This raises the possibility that sperm production rates within species may influence the TL passed on to offspring.

  October 12, 2016   doi: 10.1002/ajpa.23109   open full text
• Integrating feeding behavior, ecological data, and DNA barcoding to identify developmental differences in invertebrate foraging strategies in wild white‐faced capuchins (Cebus capucinus).
  Elizabeth K. Mallott, Paul A. Garber, Ripan S. Malhi.
  American Journal of Physical Anthropology. October 05, 2016
  Objectives Invertebrate foraging strategies in nonhuman primates often require complex extractive foraging or prey detection techniques. As these skills take time to master, juveniles may have reduced foraging efficiency or concentrate their foraging efforts on easier to acquire prey than adults. Materials and methods We use DNA barcoding, behavioral observations, and ecological data to assess age‐based differences in invertebrate prey foraging strategies in a group of white‐faced capuchins (Cebus capucinus) in northeastern Costa Rica. Invertebrate availability was monitored using canopy traps and sweep netting. Fecal samples were collected from adult female, adult male, and juvenile white‐faced capuchins (n = 225). COI mtDNA sequences were compared with known sequences in GenBank and the Barcode of Life Database. Results Frequencies of Lepidoptera and Hymenoptera consumption were higher in juveniles than in adults. A significantly smaller proportion of juvenile fecal samples contained Gryllidae and Cercopidae sequences, compared with adults (0% and 4.2% vs. 4.6% and 12.5%), and a significantly larger proportion contained Tenthredinidae, Culicidae, and Crambidae (5.6%, 9.7%, and 5.6% vs. 1.3%, 0.7%, and 1.3%). Juveniles spent significantly more time feeding and foraging than adults, and focused their foraging efforts on prey that require different skills to capture or extract. Arthropod availability was not correlated with foraging efficiency, and the rate of consumption of specific orders of invertebrates was not correlated with the availability of those same taxa. Discussion Our data support the hypothesis that juveniles are concentrating their foraging efforts on different prey than adults, potentially focusing their foraging efforts on more easily acquired types of prey.

  October 05, 2016   doi: 10.1002/ajpa.23113   open full text
• Do leprosy and tuberculosis generate a systemic inflammatory shift? Setting the ground for a new dialogue between experimental immunology and bioarchaeology.
  Fabian A. Crespo, Christopher K. Klaes, Andrew E. Switala, Sharon N. DeWitte.
  American Journal of Physical Anthropology. October 05, 2016
  It is possible that during long lasting chronic infections such as tuberculosis (TB) and leprosy individuals who generate a stronger immune response will produce a chronic shift in the systemic levels of inflammatory proteins. Consequently, the systemic immunological shift could affect inflammatory responses against other persistent pathogens such as Porphyromonas gingivalis associated with periodontal disease (PD). Objective To determine if in vitro exposure to Mycobacterium tuberculosis or M. leprae lysates impacts subsequent immune responses to P. gingivalis; and to propose a new dialogue between experimental immunology and paleopathology. Material and methods We sequentially (2 days protocol) exposed peripheral blood mononuclear cells (PBMCs) from healthy donors to bacterial lysates either from M. tuberculosis, or M. leprae, or P. gingivalis. After collecting all supernatants, we measured the expression of immune proteins TNFα and IFNγ using an enzyme‐linked immunosorbent assay. Results Early exposure (day 1) of PBMCs to M. leprae or M. tuberculosis lysates induces an inflammatory shift detected by the increase of TNFα and IFNγ when the same cells are subsequently (day 2) exposed to oral pathogen P. gingivalis. Discussion By extrapolating these results, we suggest that chronic infections, such as TB and leprosy, could generate a systemic immunological shift that can affect other inflammatory processes such the one present in PD. We propose that the presence and severity of PD should be explored as a proxy for inflammatory status or competence when reconstructing the health profile in past populations.

  October 05, 2016   doi: 10.1002/ajpa.23104   open full text
• Poundbury Camp in Context—a new Perspective on the Lives of Children from urban and rural Roman England.
  Anna Rohnbogner, Mary Elizabeth Lewis.
  American Journal of Physical Anthropology. October 03, 2016
  Objectives The current understanding of child morbidity in Roman England is dominated by studies of single sites/regions. Much of the data are derived from third to fifth century AD Poundbury Camp, Dorchester, Dorset, considered an unusual site due to high levels of non‐adult morbidity. There is little understanding of children in rural areas, and whether Poundbury Camp was representative of Romano‐British childhood. Materials and methods The study provides the first large scale analysis of child health in urban and rural Roman England, adding to the previously published intra‐site analysis of non‐adult paleopathology at Poundbury Camp. Age‐at‐death and pathology prevalence rates were reassessed for 953 non‐adults (0–17 years) from five major urban, six minor urban, and four rural sites (first to fifth century AD). The data were compared to the results from 364 non‐adults from Poundbury Camp. Results Rural sites demonstrated higher levels of infant burials, and greater prevalence of cribra orbitalia in the 1.1–2.5 year (TPR 64.3%), and 6.6–10.5 year cohorts (TPR 66.7%). Endocranial lesions were more frequent in the minor urban sample (TPR 15.9%). Three new cases of tuberculosis were identified in urban contexts. Vitamin D deficiency was most prevalent at Poundbury Camp (CPR 18.8%), vitamin C deficiency was identified more frequently in rural settlements (CPR 5.9%). Discussion The Poundbury Camp data on morbidity and mortality are not representative of patterns in Roman England and other major urban sites. Rural children suffered from a distinct set of pathologies described as diseases of deprivation, prompting reconsideration of how Romano‐British land management affected those at the bottom of the social hierarchy.

  October 03, 2016   doi: 10.1002/ajpa.23106   open full text
• Lateral enamel growth in human incisors from Çatalhöyük in Turkey.
  E. Bocaege, L.T. Humphrey.
  American Journal of Physical Anthropology. October 03, 2016
  Objectives Whereas the differences in lateral enamel growth between fossil and modern populations have been well documented in recent years, few studies report on the variability in perikymata counts and distribution between modern human populations. There is a need for information on modern human populations from a wide range of geographical regions and archaeological populations to determine whether existing patterns are representative. The aim of this paper is to document enamel surface microstructures in human teeth from a previously unknown region and time period comprehensively. Materials and methods Perikymata counts and distribution are assessed in a large sample of relatively unworn permanent incisors from the mid‐Holocene site of Çatalhöyük in Turkey. Results All four incisor types exhibit total perikymata counts that are intermediate between values for modern samples from northern Europe and South Africa. The perikymata distribution followed the modern human pattern of a marked decrease in spacing in the cervical half of the crown. Discussion The existence of regional differences in perikymata number and distribution demonstrates the importance of documenting enamel microstructures in a wider range of modern human populations, both geographically and chronologically.

  October 03, 2016   doi: 10.1002/ajpa.23069   open full text
• Skeletal assessment and secular changes in knee development: a radiographic approach.
  M.E. Boeyer, S.D. Ousley.
  American Journal of Physical Anthropology. October 03, 2016
  Objectives The purpose of this study is to conduct an analysis of ossification patterns in the distal femoral, proximal tibial, and proximal fibular epiphyses, and the patella. The results generated from this analysis will be compared with previous standards published by Elgenmark () and Garn et al. () to determine if clinical and skeletal age assessment standards should be updated for contemporary Americans. Materials and methods Using the Pediatric Radiology Interactive Atlas (Patricia), a total of 1,317 epiphyses were scored for presence or absence from radiographs of 1,056 white individuals born in or after 1990. Statistical modeling of epiphyseal appearance was conducted for all major percentiles, including the 5th and 95th percentiles through logistic regression. Results Compared with Elgenmark () and Garn et al. (), our data suggest that the distal femoral and proximal tibial epiphyses show overall earlier ossification, while the proximal fibular epiphysis shows later ossification. When examining the pooled sex 50th percentile for our data, we found that ossification timing differences are 1.2 weeks earlier in the distal femoral epiphysis, 2.1 weeks earlier in the proximal tibial epiphysis, and 1.4 years later in the proximal fibular epiphysis. Discussion The epiphyses that appear early in life, for example the distal femoral epiphysis, require gestational age information to accurately estimate appearance times. There are considerable differences between the ossification timing patterns presented in this study and those of previous standards, which did not include gestational ages. Several factors may explain the observed differences in the epiphyses of the knee including: the availability of gestational age information, the analysis of longitudinal versus cross‐sectional data, differences in socioeconomic status and prenatal care, and secular change. KEYWORDS age estimation, growth standards, ossification, skeletal maturation, subadult/juvenile growth

  October 03, 2016   doi: 10.1002/ajpa.23110   open full text
• Traumatic injury risk and agricultural transitions: A view from the American Southeast and beyond.
  Patricia M. Lambert, Martin H. Welker.
  American Journal of Physical Anthropology. September 27, 2016
  Objectives Bioarchaeological research has documented a general decline in health with the transition from foraging to farming, primarily with respect to changing patterns of morbidity. Less is known about changes in injury risk, an aspect of health more obviously tied to particular landscapes and behaviors associated with different subsistence regimes. The purpose of this research is to evaluate several hypotheses emerging from the ideal free distribution model (Fretwell & Lucas, ) that predict injury risk based on subsistence‐specific practices and land use patterns. Materials and Methods Postcranial fracture frequencies for long bones and clavicles in human skeletal remains from three Southeast U.S. regions permit examination of variability in injury risk among low‐intensity (floodplain) farmers. Published data on six hunter‐gatherer samples, four low‐intensity agriculturalist samples, and six high‐intensity agriculturalist samples comprise a comparative sample for examining variability in injury risk across three distinct subsistence traditions. Differences are evaluated using Z scores and the Fisher Exact test, Chi‐Square test, and Mann–Whitney U test. Results While statistically significant differences are apparent among low‐intensity farming groups in the Southeast sample, in the global comparison postcranial fractures are significantly less common in low‐intensity agriculturalists than in hunter‐gatherers or high‐intensity agriculturalists. Discussion The results of this study support the hypothesis that, with respect to traumatic injury risk, low‐intensity farming is a risk‐averse subsistence strategy in comparison with full‐time foraging or high‐intensity agriculture. These data suggest that it is not agriculture per se that predicts an increase in this health risk, but rather the mode and intensity of agricultural production, findings that have important ramifications for our understanding of the health consequences of major subsistence transitions.

  September 27, 2016   doi: 10.1002/ajpa.23103   open full text
• Ecogeographic variation across morphofunctional units of the human nose.
  Scott D. Maddux, Lauren N. Butaric, Todd R. Yokley, Robert G. Franciscus.
  American Journal of Physical Anthropology. September 27, 2016
  Objectives Although the internal nose is overwhelmingly responsible for heat and moisture exchange during respiration, external nasal morphology is more commonly cited as evincing climatic adaptation in humans. Here, we assess variation across all four morphofunctional units of the complete nasorespiratory tract (external pyramid, nasal aperture, internal nasal fossa, and nasopharynx) to determine which units provide the strongest evidence of climatic adaptation. Materials and Methods We employ 20 linear measurements collected on 837 modern human crania from major geographic (Arctic Circle, Asia, Australia, Europe, Africa) and climatic (polar, temperate, hot‐arid, tropical) zones. In conjunction with associated climatic and geographic data, these morphological data are employed in multivariate analyses to evaluate the associations between each of these functional nasal units and climate. Results The external pyramid and nasopharynx exhibit virtually no evidence of climate‐mediated morphology across the regional samples, while apparent associations between climate and nasal aperture morphology appear influenced by the geographic (and likely genetic) proximities of certain populations. Only the internal nasal fossa exhibits an ecogeographic distribution consistent with climatic adaptation, with crania from colder and/or drier environments displaying internal nasal fossae that are longer, taller, and narrower (especially superiorly) compared to those from hotter and more humid environments. Conclusions Our study indicates that the internal nasal fossa exhibits a stronger association with climate compared to other aspects of the human nose. Further, our study supports suggestions that regional variation in internal nasal fossa morphology reflects demands for heat and moisture exchange via adjustment of internal nasal airway dimensions. Our study thus provides empirical support for theoretical assertions related to nasorespiratory function, with important implications for understanding human nasal evolution.

  September 27, 2016   doi: 10.1002/ajpa.23100   open full text
• The Patterning Cascade Model and Carabelli's trait expression in metameres of the mixed human dentition: exploring a morphogenetic model.
  Kathleen S. Paul, Claudia M. Astorino, Shara E. Bailey.
  American Journal of Physical Anthropology. September 23, 2016
  Objectives The Patterning Cascade Model (PCM) provides an evolutionary developmental framework for exploring diversity in tooth crown form. According to the model, proximity of secondary enamel knots and tooth germ size track underlying developmental processes that dictate ultimate crown morphology (i.e., cusp number, accessory cusp presence/size). Previous research has shown the model to successfully predict variation in Carabelli's trait expression between antimeric and metameric pairs of human permanent molars. In this study, we quantify Carabelli's trait expression for metameres of the mixed dentition (dm2 and M1) and assess the PCM's potential for explaining differences in expression between the two elements. Materials and methods Crown dimensions, intercusp distances, and Carabelli's trait expression were collected from 49 subadults possessing observable dm2/M1 pairs. Wilcoxon signed‐rank tests and paired t‐tests were performed to assess whether metameres differ significantly in morphometric variables. We explored the relationships between relative intercusp distances (RICDs) and Carabelli's trait expression using proportional odds logistic regression. Results Intra‐individual dm2/M1 pairs differed significantly in Carabelli's trait expression (p = 0.01), with dm2 exhibiting higher grades of expression more commonly despite its smaller crown size. Paired molars differed in only one statistically significant RICD: metacone‐hypocone (p < 0.01). Most RICDs shared the predicted negative relationship with Carabelli's trait expression, but this relationship was only statistically significant for three RICDs in the dm2 (mean, protocone‐paracone, metacone‐hypocone). Conclusions We found mixed support for the PCM's ability to explain differences in Carabelli's trait expression between metameres of the mixed molar row. Results suggest that protocone‐paracone enamel knot spacing has the greatest influence on Carabelli's trait expression. Lack of statistical significance for many of the relationships explored may reflect limitations related to sample composition and sample size.

  September 23, 2016   doi: 10.1002/ajpa.23080   open full text
• Wear and its effects on dental topography measures in howling monkeys (Alouatta palliata).
  James D. Pampush, Jackson P. Spradley, Paul E. Morse, Arianna R. Harrington, Kari L. Allen, Doug M. Boyer, Richard F. Kay.
  American Journal of Physical Anthropology. September 16, 2016
  Objectives Three dental topography measurements: Dirichlet Normal Energy (DNE), Relief Index (RFI), and Orientation Patch Count Rotated (OPCR) are examined for their interaction with measures of wear, within and between upper and lower molars in Alouatta palliata. Potential inferences of the “dental sculpting” phenomenon are explored. Materials and methods Fifteen occluding pairs of howling monkey first molars (15 upper, 15 lower) opportunistically collected from La Pacifica, Costa Rica, were selected to sample wear stages ranging from unworn to heavily worn as measured by the Dentine Exposure Ratio (DER). DNE, RFI, and OPCR were measured from three‐dimensional surface reconstructions (PLY files) derived from high‐resolution CT scans. Relationships among the variables were tested with regression analyses. Results Upper molars have more cutting edges, exhibiting significantly higher DNE, but have significantly lower RFI values. However, the relationships among the measures are concordant across both sets of molars. DER and EDJL are curvilinearly related. DER is positively correlated with DNE, negatively correlated with RFI, and uncorrelated with OPCR. EDJL is not correlated with DNE, or RFI, but is positively correlated with OPCR among lower molars only. Discussion The relationships among these metrics suggest that howling monkey teeth adaptively engage macrowear. DNE increases with wear in this sample presumably improving food breakdown. RFI is initially high but declines with wear, suggesting that the initially high RFI safeguards against dental senescence. OPCR values in howling monkey teeth do not show a clear relationship with wear changes.

  September 16, 2016   doi: 10.1002/ajpa.23077   open full text
• On the distribution of trace element concentrations in multiple bone elements in 10 Danish medieval and post‐medieval individuals.
  Kaare Lund Rasmussen, Lilian Skytte, Paolo D'imporzano, Per Orla Thomsen, Morten Søvsø, Jesper Lier Boldsen.
  American Journal of Physical Anthropology. September 15, 2016
  Background The differences in trace element concentrations among 19 different bone elements procured from 10 archaeologically derived human skeletons have been investigated. The 10 individuals are dated archaeologically and some by radiocarbon dating to the medieval and post‐medieval period, an interval from ca. AD 1150 to ca. AD 1810. This study is relevant for two reasons. First, most archaeometric studies analyze only one bone sample from each individual; so to what degree are the bones in the human body equal in trace element chemistry? Second, differences in turnover time of the bone elements makes the cortical tissues record the trace element concentrations in equilibrium with the blood stream over a longer time earlier in life than the trabecular. Therefore, any differences in trace element concentrations between the bone elements can yield what can be termed a chemical life history of the individual, revealing changes in diet, provenance, or medication throughout life. Methods Thorough decontamination and strict exclusion of non‐viable data has secured a dataset of high quality. The measurements were carried out using Inductively Coupled Plasma Mass Spectrometry (for Fe, Mn, Al, Ca, Mg, Na, Ba, Sr, Zn, Pb and As) and Cold Vapor Atomic Absorption Spectroscopy (for Hg) on ca. 20 mg samples. Results Twelve major and trace elements have been measured on 19 bone elements from 10 different individuals interred at five cemeteries widely distributed in medieval and renaissance Denmark. The ranges of the concentrations of elements were: Na (2240–5660 µg g−1), Mg (440–2490 µg g−1), Al (9–2030 µg g−1), Ca (22‐36 wt. %), Mn (5–11450 µg g−1), Fe (32–41850 µg g−1), Zn (69–2610 µg g−1), As (0.4–120 µg g−1), Sr (101‐815 µg g−1), Ba (8‐880 µg g−1), Hg (7–78730 ng g−1), and Pb (0.8–426 µg g−1). Conclusions It is found that excess As is mainly of diagenetic origin. The results support that Ba and Sr concentrations are effective provenance or dietary indicators. Migrating behavior or changes in diet have been observed in four individuals; non‐migratory or non‐changing diet in six out of the 10 individuals studied. From the two most mobile (most changing diet) individuals in the study, it is deduced that the fastest turnover is seen in the trabecular tissues of the long bones and the hands and the feet, and that these bone elements have higher turnover rates than centrally placed trabecular bone tissue, such as from the ilium or the spine. Comparing Sr and published bone turnover times, it is concluded that the differences seen in Sr concentrations are not caused by diagenesis, but by changes of diet or provenance. Finally, it is concluded that there can be two viable interpretations of the Pb concentrations, which can either be seen as an indicator for social class or a temporal development of increased Pb exposure over the centuries.

  September 15, 2016   doi: 10.1002/ajpa.23099   open full text
• Exploring imperial expansion using an isotopic analysis of paleodietary and paleomobility indicators in Chachapoyas, Peru.
  J. Marla Toyne, Warren B. Church, Jose Luis Coronado Tello, Ricardo Morales Gamarra.
  American Journal of Physical Anthropology. September 15, 2016
  Objectives Inca imperial strategies of political and territorial expansion varied across conquered regions depending on local ecology and cultural resistance, and Chachapoya peoples in Peru's forested northeastern Andes were renowned for their rebellions against the invaders. The cliff tombs of Los Pinchudos (AD 1470–1535) present opportunities to use stable isotopes to: (1) explore dietary and mobility patterns from a mortuary community interred at a site attributed to the poorly‐known Chachapoya culture during the period of Inca domination, and (2) explore the origins of the individuals as either local or foreign (Inca). Using biochemical tracers, we can help resolve the impact of foreign influence and changes in population and social structure during imperial occupation. Materials and Methods While it is difficult to reconstruct individual life histories from incomplete skeletons, stable isotopic analysis of multiple skeletal tissues provides a direct means of characterizing diet and residential mobility. Values of stable carbon (δ13C), nitrogen (δ15N), and oxygen isotope (δ18O) ratios were determined in bone and dentine collagen and bone and enamel carbonate from 28 samples (11 paired tissues) from males, females, and juveniles from Los Pinchudos. Results Dietary signatures are consistent with a mixed but more C3‐based plant and protein‐based diet with moderate proportions of terrestrial animals. Oxygen isotopic values demonstrate limited variation between paired tissues, with a few possible nonlocal individuals buried in one particular tomb at the site. Compared to other Andean areas that underwent imperial domination, these data do not demonstrate expected dietary shifts. Discussion These are the first isotopic data from a Chachapoya site and our research shows evidence for minimal non‐local presence in this commingled burial assemblage. The regional diet reconstructed at Los Pinchudos (2850 masl) focused on resources of higher altitude tuber crops, beans, and grains (C3) and terrestrial protein rather than on lower elevation grasses such as maize (C4) as in other highland Andean regions under Inca control. During imperial domination, inhabitants of this region appropriated Inca materials goods but continued to construct tombs in the local manner even though a potentially diverse population was occupying them.

  September 15, 2016   doi: 10.1002/ajpa.23085   open full text
• Continuity or conquest? A multi‐isotope approach to investigating identity in the Early Iron Age of the Southern Levant.
  Lesley A. Gregoricka, Susan Guise Sheridan.
  American Journal of Physical Anthropology. September 15, 2016
  Objectives Across the Mediterranean and Near East, the transition from the Late Bronze Age (ca. 1550–1200 BC) to the Early Iron Age (ca. 1200–900 BC) was accompanied by profound cultural change. While this transformation was initially attributed to invasion or conquest, more recent, nuanced interpretations of archaeological and biological data now emphasize the decline of palatial economies, a shift away from centralized political authority, and internal social restructuring amidst rapid climate change in lieu of “collapse.” Correspondingly, the hypothesis that Early Iron Age populations in Palestine represent the same ethnic group whose culture nevertheless underwent considerable change by actively adapting to internal and external forces was tested using biogeochemical data from individuals interred within an Early Iron Age tomb at the site of Tell Dothan. Materials and Methods Human dental enamel from molars (n = 43) recovered from Tomb I at Tell Dothan was analyzed for radiogenic strontium isotope ratios and stable oxygen and carbon (VPDB) isotope values. Results Strontium (mean = 0.70816 ± 0.00005, 1σ) isotope ratios, as well as oxygen (mean = −2.3 ± 0.7‰, 1σ) and carbon (mean = −11.9 ± 0.5‰, 1σ) isotope values, all display little variability. Discussion The absence of non‐locals at Tell Dothan indicates that population replacement does not adequately explain the sociopolitical changes observed in the archaeological record. Further, homogeneity among isotope values is indicative of a community that was not highly mobile, suggesting that decentralization and a corresponding transition to a more mobile lifestyle may not accurately reflect the adaptive strategies of all human groups during this period as a mechanism to cope with social and environmental change.

  September 15, 2016   doi: 10.1002/ajpa.23086   open full text
• Age estimation of immature human skeletal remains from the metaphyseal and epiphyseal widths of the long bones in the post‐natal period.
  Hugo F. V. Cardoso, John M. Vandergugten, Louise T. Humphrey.
  American Journal of Physical Anthropology. September 10, 2016
  Objectives This study provides regression and classical calibration models for the estimation of age from the dimensions of the metaphyses and epiphyses of the six long bones. Methods A sample of 148 known sex and age individuals (56 females and 92 males), aged between birth and 12 years of age, selected from Portuguese and English skeletal collections. Age estimation models were obtained separately for each sex and for the sexes combined, for the entire sample and for the sample divided into two subsamples at the age of 2 years. Results The best performing epiphysis is the proximal epiphysis of the tibia. For the metaphyses, the distal metaphysis of the tibia and the proximal metaphysis of the femur are best for individuals below and above 2 years of age, respectively. Growth of the metaphyses is similar to that of the diaphysis. Results suggest that age can be as accurately estimated from the width of the metaphyses and epiphyses as from the length of the diaphyses, or as from the length of the deciduous and permanent teeth. Conclusions These models may be useful for fragmentary material in both archaeological and forensic contexts. However, due to the background of the samples, the models would be most applicable to individuals exposed to adverse environmental conditions during growth and development. Metaphyseal and epiphyseal widths may be less affected by ecological conditions than diaphyseal length.

  September 10, 2016   doi: 10.1002/ajpa.23081   open full text
• First insight into the Neolithic subsistence economy in the north‐east Iberian Peninsula: paleodietary reconstruction through stable isotopes.
  Maria Fontanals‐Coll, M. Eulàlia Subirà, Marta Díaz‐Zorita Bonilla, Juan F. Gibaja.
  American Journal of Physical Anthropology. August 26, 2016
  Objectives The study of subsistence strategies among Neolithic communities in north‐east Iberia, late‐fifth to early‐fourth millennia cal BC, enables a more in‐depth study of the activities and behavior of the inhabitants of this region, where paleodiets have been little studied. The objectives of this study are, therefore, to determine the diet and subsistence patterns of those communities and to consider whether any relation existed between their subsistence strategies and environmental, geographic, and/or social factors. Materials and Methods Bone samples from 25 middle Neolithic human individuals at seven archeological sites and comparative faunal samples were analyzed, and compared with contemporary series in Mediterranean Europe. Carbon and nitrogen isotope ratios (δ13C and δ15N) of bone collagen were studied to determine the dietary patterns. Results Dietary habits proved to be similar between communities, apart from some interpopulational variations in subsistence strategies. Their diet was based on C3 terrestrial resources with a major vegetal protein component. Discussion The reported variations in interpopulational subsistence strategies among the compared Mediterranean societies do not seem to be directly related to the settlement region. Together with archeological data, this indicates the influence of socioeconomic factors in the Neolithic human diet. A general tendency toward a lesser use of aquatic resources is seen in this period in Iberia and the rest of the Mediterranean, as also documented for contemporary communities in the west and north of Europe. The data obtained will be important for further studies of socioeconomic patterns in European Neolithic societies.

  August 26, 2016   doi: 10.1002/ajpa.23083   open full text
• Cannibalism versus funerary defleshing and disarticulation after a period of decay: comparisons of bone modifications from four prehistoric sites.
  Silvia M. Bello, Rosalind Wallduck, Vesna Dimitrijević, Ivana Živaljević, Chris B. Stringer.
  American Journal of Physical Anthropology. August 25, 2016
  Objectives Humanly induced modifications on human and non‐human bones from four archaeological sites of known funerary rituals (one interpreted as cannibalism and three interpreted as funerary defleshing and disarticulation after a period of decay) were analyzed to ascertain whether macromorphological and micromorphological characteristics of cut marks can be used to distinguish cannibalistic from secondary burial practices. Material and methods Four collections were analyzed: the Magdalenian assemblage from Gough's Cave (UK) and the Mesolithic‐Neolithic bone samples from Lepenski Vir, Padina and Vlasac (Serbia). A total of 647 cut marks (345 on human and 302 on non‐human remains) were imaged and measured using an optical surface measurement system, the Alicona InfiniteFocus, housed at the Natural History Museum (London, UK). Results The frequency of cut marks at Gough's Cave exceeds 65%, while it is below 1% in the Serbian sites, and no human tooth marks and only one case of percussion damage have been observed on the three Serbian collections. The distribution of cut marks on human bones is comparable in the four assemblages. Cannibalized human remains, however, present a uniform cut mark distribution, which can be associated with disarticulation of persistent and labile articulations, and the scalping and filleting of muscles. For secondary burials where modification occurred after a period of decay, disarticulation marks are less common and the disarticulation of labile joints is rare. The micromorphometric analyses of cut marks on human and non‐human remains suggest that cut marks produced when cleaning partially decayed bodies are significantly different from cut marks produced during butchery of fresh bodies. Conclusions A distinction between cannibalism and secondary treatment of human bodies can be made based on frequency, distribution and micromorphometric characteristics of cut marks.

  August 25, 2016   doi: 10.1002/ajpa.23079   open full text
• Human energy expenditure, allocation, and interactions in natural temperate, hot, and cold environments.
  Cara Ocobock.
  American Journal of Physical Anthropology. August 25, 2016
  Objective The aim of this research is to analyze how energy is allocated differently in temperate, hot, and cold environments among National Outdoor Leadership School students. Method Basal metabolic rate, physical activity, thermoregulation, and the thermic effect of food were estimated to determine the total energy expenditure and energy allocation differences among a group of healthy, highly active adults (N = 59) participating in National Outdoor Leadership School courses in the western United States. Two of these courses took place in both hot and temperate climates (N = 22) and the other two in both temperate and cold climates (N = 28). Data from a pilot study (N = 6) in a temperate climate were also included. Each climate regime lasted for one month. Results Total energy expenditure values were statistically equivalent in temperate and hot climates (p = .97). However, subjects experienced significantly higher total energy expenditures in cold climates (p < .0001), expending an additional ∼1550 kcal day−1. There is a significant interaction between physical activity and thermoregulation, such that physical activity reduces thermoregulatory costs in cold climates, but increases it in hot climates. Conclusions Dissection of the energy budget revealed that total energy expenditure is significantly higher in cold climates. This is due to a combination of high levels of physical activity and high thermoregulatory costs. High levels of physical activity may substantially lower the cost of thermoregulation in cold climates, and this interaction should be taken into account when estimating TEE.

  August 25, 2016   doi: 10.1002/ajpa.23071   open full text
• Fecal carbon and nitrogen isotopic analysis as an indicator of diet in Kanyawara chimpanzees, Kibale National Park, Uganda.
  Caroline A. Phillips, Tamsin C. O'Connell.
  American Journal of Physical Anthropology. August 24, 2016
  Objectives The shorter‐term overview from feces provides scope to investigate dietary fluctuations. We assess the correlation of stable isotopic fecal values with recorded seasonal diet of 10 adult chimpanzees (P. t. schweinfurthii) of the Kanyawara community (Kibale National Park, Uganda) and whether fecal nitrogen levels (%N) indicate a change in crude protein intake. Materials and Methods We recorded food eaten by each ape and collected both concurrent fecal samples (N = 115) and plant foods eaten by this community (N = 64). We compared fecal δ13C and δ15N values (also %N) with: (a) plant values; (b) feeding data; and (c) food‐items found macroscopically in the fecal samples. Interspecies and intraspecies differences in plant and fecal isotope values (and %N) as well as seasonality in diet were determined using parametric and nonparametric tests. Results No difference in plant δ13C and δ15N values was found at intraspecies or interspecies level. Fecal isotope values reflected a diet of C3 plants from evergreen forest vegetation. Seasonal differences in δ13C and δ15N corresponded with aspects of feeding and fecal macroscopic data, but only at community level. A change in crude protein intake was not indicated from %N content. Discussion This study further validates the use of staple isotope analyses of primate feces to provide a dietary overview, revealing seasonal differences at community level; however, conclusive results may be limited for individuals when using short sampling periods. Further study of variables that influence fecal %N content is also suggested to interpret crude protein intake.

  August 24, 2016   doi: 10.1002/ajpa.23073   open full text
• A study of the peopling of Greenland using next generation sequencing of complete mitochondrial genomes.
  Maria Lopopolo, Claus Børsting, Vania Pereira, Niels Morling.
  American Journal of Physical Anthropology. August 24, 2016
  Objectives The Greenlandic population history is characterized by a number of migrations of people of various ethnicities. In this work, the analysis of the complete mtDNA genome aimed to contribute to the ongoing debate on the origin of current Greenlanders and, at the same time, to address the migration patterns in the Greenlandic population from a female inheritance demographic perspective. Methods We investigated the maternal genetic variation in the Greenlandic population by sequencing the whole mtDNA genome in 127 Greenlandic individuals using the Illumina MiSeq® platform. Results All Greenlandic individuals belonged to the Inuit mtDNA lineages A2a, A2b1, and D4b1a2a1. No European haplogroup was found. Discussion The mtDNA lineages seem to support the hypothesis that the Inuit in Greenland are descendants from the Thule migration. The results also reinforce the importance of isolation and genetic drift in shaping the genetic diversity in Greenlanders. Based on the mtDNA sequences, the Greenlandic Inuit are phylogenetically close to Siberian groups and Canadian Inuit.

  August 24, 2016   doi: 10.1002/ajpa.23074   open full text
• Positive selection of lactase persistence among people of Southern Arabia.
  Riad Bayoumi, Sara De Fanti, Marco Sazzini, Cristina Giuliani, Andrea Quagliariello, Eugenio Bortolini, Alessio Boattini, Molham Al‐Habori, Adel Sharaf Al‐Zubairi, Jeffrey I. Rose, Giovanni Romeo, Abdulrahim Al‐Abri, Donata Luiselli.
  American Journal of Physical Anthropology. August 18, 2016
  Objective Frequency patterns of the lactase persistence (LP)‐associated −13,915 G allele and archaeological records pointing to substantial role played by southern regions in the peopling and domestication processes that involved the Arabian Peninsula suggest that Southern Arabia plausibly represented the center of diffusion of such adaptive variant. Nevertheless, a well‐defined scenario for evolution of Arabian LP is still to be elucidated and the burgeoning archaeological picture of complex human migrations occurred through the peninsula is not matched by an equivalent high‐resolution description of genetic variation underlying this adaptive trait. To fill this gap, we investigated diversity at a wide genomic interval surrounding the LCT gene in different Southern Arabian populations. Methods 40 SNPs were genotyped to characterize LCT profiles of 630 Omani and Yemeni individuals to perform population structure, linkage disequilibrium, population differentiation‐based and haplotype‐based analyses. Results Typical Arabian LP‐related variation was found in Dhofaris and Yemenis, being characterized by private haplotypes carrying the −13,915 G allele, unusual differentiation with respect to northern groups and conserved homozygous haplotype‐blocks, suggesting that the adaptive allele was likely introduced in the Arabian gene pool in southern populations and was then subjected to prolonged selective pressure. Conclusion By pointing to Yemen as one of the best candidate centers of diffusion of the Arabian‐specific adaptive variant, obtained results indicate the spread of indigenous groups as the main process underlying dispersal of LP along the Arabian Peninsula, supporting a refugia model for Arabian demic movements occurred during the Terminal Pleistocene and Early Holocene.

  August 18, 2016   doi: 10.1002/ajpa.23072   open full text
• Hot flash report and measurement among Bangladeshi migrants, their London neighbors, and their community of origin.
  L. L. Sievert, K. Begum, T. Sharmeen, L. Murphy, B. W. Whitcomb, O. Chowdhury, S. Muttukrishna, G. R. Bentley.
  American Journal of Physical Anthropology. August 18, 2016
  Objectives To examine hot flashes in relation to climate and activity patterns, and to compare subjective and objective hot flashes among Bangladeshi immigrants to London, their white London neighbors, and women still living in their community of origin, Sylhet, Bangladesh (“sedentees”). Methods Ninety‐five women, aged 40–55, wore the Biolog ambulatory hot flash monitor. Objective measurements and subjective hot flash reports were examined in relation to demographic, reproductive, anthropometric, and lifestyle variables; temperature and humidity at 12:00 and 18:00; and time spent on housework and cooking. Concordance of objective and subjective hot flashes was assessed by Kappa statistics and by sensitivity of hot flash classification. Results During the study period, Bangladeshi sedentees reported more subjective hot flashes (p < .05), but there was no difference in number of objective hot flashes. White Londoners were more likely to describe hot flashes on their face and neck compared to Bangladeshis (p < .05). Sedentees were more likely to describe hot flashes on their feet (p < .05). Postmenopausal status, increasing parity, and high levels of housework were significant determinants of subjective hot flashes, while ambient temperature and humidity were not. Measures of subjective/objective concordance were low but similar across groups (10–20%). The proportion of objective hot flashes that were also self‐reported was lowest among immigrants. Discussion Hot flashes were not associated with warmer temperatures, but were associated with housework and with site‐specific patterns of cooking. The number of objective hot flash measures did not differ, but differences in subjective experience suggest the influence of culture.

  August 18, 2016   doi: 10.1002/ajpa.23062   open full text
• Estimation of stature in archaeological human skeletal remains from Britain.
  S. Mays.
  American Journal of Physical Anthropology. August 18, 2016
  Objectives For archaeological populations of northwest European origin, the Trotter and Gleser () “White” equations are generally used to estimate stature from long‐bone length. The aim of this research is to investigate the reliability of these formulae for this purpose. Materials and methods Stature estimated using the Trotter and Gleser formulae was evaluated by comparing estimates with anatomically reconstructed stature in adult skeletons (N = 40) from Mediaeval England. Performance of the Trotter and Gleser equations based on femur length was compared (using standard error of the estimate (SEE) and mean percentage error (%error)) with others that have been derived from archaeological and recent European ancestry populations. Performance of ordinary least squares (OLS) and reduced major axis (RMA) versions of some of the equations was also evaluated. Results 14 male and 11 female femoral equations were investigated. For females, the original (OLS) Trotter and Gleser “White” equations produced the lowest SEE and %error. For the males, the most reliable was the RMA version of the Trotter and Gleser “White” WWII equation; the Trotter and Gleser equations based on the Korean War dead performed poorly. Discussion In an archaeological target population, stature estimation equations devised using archaeological reference populations from a similar ecogeographic zone did not perform better than those based on recent populations. There was no indication that either the RMA or OLS approach produced consistently lower SEE and %error, but the former more faithfully represented the variation in anatomically reconstructed stature present in the study group.

  August 18, 2016   doi: 10.1002/ajpa.23068   open full text
• Trabecular architecture in the thumb of Pan and Homo: implications for investigating hand use, loading, and hand preference in the fossil record.
  Nicholas B. Stephens, Tracy L. Kivell, Thomas Gross, Dieter H. Pahr, Richard A. Lazenby, Jean‐Jacques Hublin, Israel Hershkovitz, Matthew M. Skinner.
  American Journal of Physical Anthropology. August 08, 2016
  Objectives Humans display an 85–95% cross‐cultural right‐hand bias in skilled tasks, which is considered a derived behavior because such a high frequency is not reported in wild non‐human primates. Handedness is generally considered to be an evolutionary byproduct of selection for manual dexterity and augmented visuo‐cognitive capabilities within the context of complex stone tool manufacture/use. Testing this hypothesis requires an understanding of when appreciable levels of right dominant behavior entered the fossil record. Because bone remodels in vivo, skeletal asymmetries are thought to reflect greater mechanical loading on the dominant side, but incomplete preservation of external morphology and ambiguities about past loading environments complicate interpretations. We test if internal trabecular bone is capable of providing additional information by analyzing the thumb of Homo sapiens and Pan. Materials and methods We assess trabecular structure at the distal head and proximal base of paired (left/right) first metacarpals using micro‐CT scans of Homo sapiens (n = 14) and Pan (n = 9). Throughout each epiphysis we quantify average and local bone volume fraction (BV/TV), degree of anisotropy (DA), and elastic modulus (E) to address bone volume patterning and directional asymmetry. Results We find a right directional asymmetry in H. sapiens consistent with population‐level handedness, but also report a left directional asymmetry in Pan that may be the result of postural and/or locomotor loading. Conclusion We conclude that trabecular bone is capable of detecting right/left directional asymmetry, but suggest coupling studies of internal structure with analyses of other skeletal elements and cortical bone prior to applications in the fossil record.

  August 08, 2016   doi: 10.1002/ajpa.23061   open full text
• Population structure from NOS genes correlates with geographical differences in coronary incidence across Europe.
  Robert Carreras‐Torres, Albert Ferran, Daniela Zanetti, Esther Esteban, Laurent Varesi, Naris Pojskic, Valentina Coia, Hassen Chaabani, Marc Via, Pedro Moral.
  American Journal of Physical Anthropology. August 08, 2016
  Objectives The population analysis of cardiovascular risk and non‐risk genetic variation can help to identify adaptive or random demographic processes that shaped coronary incidence variation across geography. Material and Methods In this study, 114 single nucleotide polymorphisms and 17 tandem repeat polymorphisms from Nitric Oxide Synthases (NOS) regions were analyzed in 1686 individuals from 35 populations from Europe, North Africa, and the Middle East. NOS genes encode for key enzymes on nitric oxide availability, which is involved in several cardiovascular processes. These genetic variations were used to test for selection and to infer the population structure of NOS regions. Moreover, we tested whether the variation in the incidence of coronary events and in the levels of classical risk factors in 11 of these European populations could be explained by the population structure estimates. Results Our results supported, first, the absence of clear signs of selection for NOS genetic variants associated with cardiovascular diseases, and second, the presence of a continuous genetic pattern of variation across European and North African populations without a Mediterranean barrier for gene flow. Finally, population structure estimates from NOS regions are closely correlated with coronary event rates and classical risk parameters (explaining 39–98%) among European populations. Conclusion Our results reinforce the hypothesis that genetic bases of cardiovascular diseases and associated complex phenotypes could be geographically shaped by random demographic processes.

  August 08, 2016   doi: 10.1002/ajpa.23063   open full text
• Seasonal importance of flowers to Costa Rican capuchins (Cebus capucinus imitator): Implications for plant and primate.
  Jeremy D. Hogan, Amanda D. Melin, Krisztina N. Mosdossy, Linda M. Fedigan.
  American Journal of Physical Anthropology. August 05, 2016
  Objectives Our goal is to investigate flower foraging by capuchin monkeys, a behavior rarely studied in wild primates. We ask what drives seasonal variation in florivory rates: flower quality and abundance or fluctuations in fruit and invertebrate abundances. We explore how capuchins affect the reproductive success of flower food species by quantifying the potential pollination rate. Materials and Methods We followed capuchin groups from dawn to dusk and recorded all flower foraging bouts. Flower food nutritional composition was compared to fruit and invertebrate foods. We recorded overall flower, fruit, and invertebrate abundances and compared the rate of flower foraging to these. We estimated the likelihood of pollination from the proportion of flower patch visits to each plant species that satisfied minimum behavioral requirements. Results Flower eating was highly seasonal, and was significantly negatively related to overall fruit and invertebrate abundance but not flower abundance. Although smaller than most fruits, flowers were nutritionally comparable to fruit foods by dry mass and contained higher average concentrations of protein. Capuchins are likely pollinators for Luehea speciosa; most foraging visits to this species occurred in a manner that makes outcrossing or geitonogamous pollination likely. Discussion Flowers are an important seasonal resource for capuchins. Flowers likely act as fallback foods during periods of reduced fruit and invertebrate abundance, and may exert evolutionary pressure disproportionate to their consumption. Capuchin florivory likely affects the reproductive success of some plants, potentially shaping forest structure. Our study illustrates the value of assessing the importance of rare foods in the primate diet.

  August 05, 2016   doi: 10.1002/ajpa.23059   open full text
• Partially shared consensus decision making and distributed leadership in vervet monkeys: older females lead the group to forage.
  Hillary C. Lee, Julie A. Teichroeb.
  American Journal of Physical Anthropology. July 30, 2016
  Objectives Group living can be advantageous, but for motile organisms, collective movements become necessary. We are just beginning to understand the many ways that animal groups make movement decisions and maintain cohesion. We examined start attempts and success in leading collective group movements in vervet monkeys (Chlorocebus pygerythrus) characterized by matrilineal groups and territoriality. Materials and methods We recorded 179 start attempts in a single group of vervets at Lake Nabugabo, Uganda and examined individual success in three situations (departing from sleeping site, moving to forage, returning to sleeping site) relative to dominance rank, age, and sex. Results Sex and age were associated with both the number of start attempts and success in leading group movements, but there was no effect of dominance rank. Older females were most successful at leading group movements, especially toward foraging sites, while adult and subadult males almost always led the group out of the sleeping site. Discussion Collective group movements in vervet monkeys appear to be based on distributed leadership and partially shared consensus decision making. Older females may be repositories of ecological knowledge, resulting in their success at leading the group to forage. Male motivation to lead the way out of the sleeping site appeared related to accessing human food sources before other group members. Young natal males achieved some success leading group progressions because they were motivated to make many initiations, which may be related to their life‐stage. These results give us a better understanding of the processes underlying collective movements in cohesive animal groups.

  July 30, 2016   doi: 10.1002/ajpa.23058   open full text
• Associations between male testosterone and immune function in a pathogenically stressed forager‐horticultural population.
  Benjamin C. Trumble, Aaron D. Blackwell, Jonathan Stieglitz, Melissa Emery Thompson, Ivan Maldonado Suarez, Hillard Kaplan, Michael Gurven.
  American Journal of Physical Anthropology. July 28, 2016
  Objectives Despite well‐known fitness advantages to males who produce and maintain high endogenous testosterone levels, such phenotypes may be costly if testosterone‐mediated investment in reproductive effort trade‐off against investment in somatic maintenance. Previous studies of androgen‐mediated trade‐offs in human immune function find mixed results, in part because most studies either focus on a few indicators of immunity, are confounded by phenotypic correlation, or are observational. Here the association between male endogenous testosterone and 13 circulating cytokines are examined before and after ex vivo antigen stimulation with phytohemagglutinin (PHA) and lipopolysaccharides (LPS) in a high pathogen population of Bolivian forager‐horticulturalists. Materials and methods A Milliplex 13‐plex cytokine panel measured cytokine concentration in whole blood samples from 109 Tsimane men aged 40–89 (median = 50 years) before and after antigen stimulation with PHA and LPS. Urinary testosterone was measured via enzyme immunoassay, demographic, and anthropometric data were collected as part of the Tsimane Health and Life History Project. Results Higher endogenous testosterone was associated with down‐regulated responses in all cytokines after PHA stimulation (but significantly in only 2/13 cytokines), controlling for age and body mass index. In contrast, testosterone was not significantly associated with down‐regulation of cytokines after LPS stimulation. MANOVAs indicate that men with higher testosterone showed reduced cytokine responses to PHA compared with LPS (p = 0.0098). Discussion Endogenous testosterone appears to be immunomodulatory rather than immunosuppressive. Potentially costlier forms of immune activation like those induced by PHA (largely T‐cell biased immune activation) are down‐regulated in men with higher testosterone, but testosterone has less impact on potentially less costly immune activation following LPS stimulation (largely B‐cell mediated immunity).

  July 28, 2016   doi: 10.1002/ajpa.23054   open full text
• Maternal height and its relationship to offspring birth weight and adiposity in 6‐ to 10‐year‐old Maya children from poor neighborhoods in Merida, Yucatan.
  Hugo Azcorra, Federico Dickinson, Sudip Datta Banik.
  American Journal of Physical Anthropology. July 28, 2016
  Objective To analyze the relationship between maternal height, offspring birth weight, and adiposity at 6–10 years of age in a sample of 197 mother–child dyads from Merida, Mexico. Materials and methods During 2008–2009 and 2011–2013, measurements were taken of maternal height and weight; and height, waist circumference (WC), and skinfolds (triceps, subscapular, and suprailiac) of their children. Participant body composition was estimated using a bioelectrical impedance analyzer. A questionnaire was applied to document household socioeconomic conditions. Multiple linear regression models were used to study the association between maternal height, offspring birth weight and fat mass index (FMI), WC, and sum of skinfolds (SumSkfZ) in boys and girls, separately. Results After adjusting for child age and household socioeconomic conditions, maternal height was identified to be significantly associated (p < .05) with FMI, WC, and SumSkf only in boys. In all models, child adiposity was inversely related to maternal height. Offspring birth weight was not associated with any adiposity parameter. Discussion The results suggest that maternal nutritional history as reflected in short maternal stature is associated with higher body fat in children, and that male offspring are more vulnerable to intergenerational influences.

  July 28, 2016   doi: 10.1002/ajpa.23057   open full text
• Morphological and functional implications of sexual dimorphism in the human skeletal thorax.
  Daniel García‐Martínez, Nicole Torres‐Tamayo, Isabel Torres‐Sanchez, Francisco García‐Río, Markus Bastir.
  American Journal of Physical Anthropology. July 22, 2016
  Objectives The human respiratory apparatus is characterized by sexual dimorphism, the cranial airways of males being larger (both absolutely and relatively) than those of females. These differences have been linked to sex‐specific differences in body composition, bioenergetics, and respiratory function. However, whether morpho‐functional variation in the thorax is also related to these features is less clear. We apply 3D geometric morphometrics to study these issues and their implications for respiratory function. Material and methods Four hundred two landmarks and semilandmarks were measured in CT‐reconstructions of rib cages from adult healthy subjects (Nmale = 18; Nfemale = 24) in maximal inspiration (MI) and maximal expiration (ME). After Procrustes registration, size and shape data were analyzed by mean comparisons and regression analysis. Respiratory function was quantified through functional size, which is defined as the difference of rib cage size between MI and ME. Results Males showed significantly larger thorax size (p < .01) and functional size (p < .05) than females. In addition, the 3D‐shape differed significantly between sexes (p < .01). Male rib cages were wider (particularly caudally) and shorter, with more horizontally oriented ribs when compared to females. While thorax widening and rib orientation were unrelated to allometry, thorax shortening showed a slight allometric signal. Conclusions Our findings are in line with previous research on sexual dimorphism of the respiratory system. However, we add that thorax shortening observed previously in males is the only feature caused by allometry. The more horizontally oriented ribs and the wider thorax of males may indicate a greater diaphragmatic contribution to rib cage kinematics than in females, and differences in functional size fit with the need for greater oxygen intake in males.

  July 22, 2016   doi: 10.1002/ajpa.23051   open full text
• The magnitude of changes in linear growth within Taiwanese families: intrinsic sex‐associated biology, socially mediated behaviors, or both?
  Bruce Floyd.
  American Journal of Physical Anthropology. July 21, 2016
  Objective This study evaluates competing hypotheses about implications of greater female growth canalization for differences in male and female growth as developmental settings improve. Participants and Methods Intergenerational declines in gender bias and rapid economic growth in Taiwan permit assessment of the two hypotheses using anthropometric and background information from 107 Taiwanese parents and their young adult offspring. Differences in parents' values were first evaluated across grandfathers' occupational status categories reflecting good to relatively poor early circumstances in the parental generation. The extent of intergenerational change in heights or knee heights within 56 father–son pairs were then compared with those in 51 statistically independent mother–daughter pairs across the same occupational categories using repeated measures analyses. Results Change in mean heights and knee heights across grandfathers' occupational categories were noticeably greater for fathers than mothers. Overall, intergenerational gains within families in height and knee height were statistically significant (p < 0.0005) in father–son (3.89 cm; 1.85 cm) and mother–daughter pairs (4.14 cm; 1.67 cm). However, among families where grandfather's occupations were “privileged,” father–son pairs are similar in average height (Δ = −0.36 cm) and knee height (Δ = 0.53 cm) while mothers were significantly shorter (Δ = 3.88 cm) with shorter knee heights (Δ = 1.74 cm) than their daughters. Discussion The hypothesis that females are inherently less capable of responding to growth promoting characteristics of early environments is not supported. Intergenerational declines in male preference combined with rapid but equitable economic growth better account for intergenerational changes reported.

  July 21, 2016   doi: 10.1002/ajpa.23048   open full text
• Dental remains of cebid platyrrhines from the earliest late Miocene of Western Amazonia, Peru: Macroevolutionary implications on the extant capuchin and marmoset lineages.
  Laurent Marivaux, Sylvain Adnet, Ali J. Altamirano‐Sierra, François Pujos, Anusha Ramdarshan, Rodolfo Salas‐Gismondi, Julia V. Tejada‐Lara, Pierre‐Olivier Antoine.
  American Journal of Physical Anthropology. July 19, 2016
  Objectives Undoubted fossil Cebidae have so far been primarily documented from the late middle Miocene of Colombia, the late Miocene of Brazilian Amazonia, the early Miocene of Peruvian Amazonia, and very recently from the earliest Miocene of Panama. The evolutionary history of cebids is far from being well‐documented, with notably a complete blank in the record of callitrichine stem lineages until and after the late middle Miocene (Laventan SALMA). Further documenting their evolutionary history is therefore of primary importance. Material Recent field efforts in Peruvian Amazonia (Contamana area, Loreto Department) have allowed for the discovery of an early late Miocene (ca. 11 Ma; Mayoan SALMA) fossil primate‐bearing locality (CTA‐43; Pebas Formation). In this study, we analyze the primate material, which consists of five isolated teeth documenting two distinct Cebidae: Cebus sp., a medium‐sized capuchin (Cebinae), and Cebuella sp., a tiny marmoset (Callitrichinae). Results Although limited, this new fossil material of platyrrhines contributes to documenting the post‐Laventan evolutionary history of cebids, and besides testifies to the earliest occurrences of the modern Cebuella and Cebus/Sapajus lineages in the Neotropics. Regarding the evolutionary history of callitrichine marmosets, the discovery of an 11 Ma‐old fossil representative of the modern Cebuella pushes back by at least 6 Ma the age of the Mico/Cebuella divergence currently proposed by molecular biologists (i.e., ca. 4.5 Ma). This also extends back to > 11 Ma BP the divergence between Callithrix and the common ancestor (CA) of Mico/Cebuella, as well as the divergence between the CA of marmosets and Callimico (Goeldi's callitrichine). Discussion This discovery from Peruvian Amazonia implies a deep evolutionary root of the Cebuella lineage in the northwestern part of South America (the modern western Amazon basin), slightly before the recession of the Pebas mega‐wetland system (PMWS), ca. 10.5 Ma, and well‐before the subsequent establishment of the Amazon drainage system (ca. 9–7 Ma). During the late middle/early late Miocene interval, the PMWS was seemingly not a limiting factor for dispersals and widespread distribution of terrestrial mammals, but it was also likely a source of diversification via a complex patchwork of submerged/emerged lands varying through time.

  July 19, 2016   doi: 10.1002/ajpa.23052   open full text
• Fetal and neonatal maxillary ontogeny in extant humans and the utility of prenatal maxillary morphology in predicting ancestral affiliation.
  Christina L. Nicholas.
  American Journal of Physical Anthropology. July 13, 2016
  Objectives The midface of extant Homo sapiens is known to undergo shape changes through fetal and neo‐natal ontogeny; however, little work has been done to quantify these shape changes. Further, while midfacial traits which vary in frequency between populations of extant humans are presumed to develop prenatally, patterns of population‐specific variation maxillary shape across ontogeny are not well documented. Only one study of fetal ontogeny which included specific discussion of the midface has taken a three‐dimensional geometric morphometric approach, and that study was limited to one population (Japanese). The present research project seeks to augment our understanding of fetal maxillary growth patterns, most especially in terms of intraspecific variation. Materials and Methods Three‐dimensional coordinate landmark data were collected on the right maxillae of 102 fetal and neo‐natal individuals from three groups (Euro‐American, African‐American, “Mixed Ancestry”). Results Shape changes were seen mainly in the lateral wall of the piriform aperture, the anterior nasal spine, and the subnasal alveolar region. The greatest difference across age groups (second trimester, third trimester, neonates) was between the second and third trimester. Euro‐Americans and African‐Americans clustered by population and differences in midfacial morphology related to ancestry could be discerned as early as the second trimester (p = .002), indicating that population variation in maxillary morphology appears very early in ontogeny. Discussion The midface is a critical region of the skull for assessing ancestry and these results indicate that maxillary morphology may be useful for estimating ancestry for prenatal individuals as young as the second trimester.

  July 13, 2016   doi: 10.1002/ajpa.23043   open full text
• Food and pathogen adaptations in the Angolan Namib desert: Tracing the spread of lactase persistence and human African trypanosomiasis resistance into southwestern Africa.
  Joana C. Pinto, Sandra Oliveira, Sérgio Teixeira, Dayana Martins, Anne‐Maria Fehn, Teresa Aço, Magdalena Gayà‐Vidal, Jorge Rocha.
  American Journal of Physical Anthropology. July 12, 2016
  Objectives: We investigated the frequency distribution and haplotype diversity of human African trypanosomiasis (HAT) resistance and lactase persistence (LP) variants in populations from the Angolan Namib to trace the spread of these genetic adaptations into southwestern Africa. Materials and Methods: We resequenced two fragments of the LCT enhancer and the APOL1 gene and genotyped flanking short tandem repeat loci in six groups with different subsistence traditions living in the Angolan Namib, and in a comparative dataset including other populations from Africa and Europe. LP in the Angolan Namib is represented by the −14010*C allele, which is associated with a predominant haplotype that is shared with other southern and eastern African populations. While LP was found to be more frequent in foragers than in pastoralists, the frequencies of the two APOL1 variants associated with HAT‐resistance (G1 and G2) did not differ between the two groups. The G1 allele is mostly associated with a single widespread haplotype. The G2 allele is linked to several haplotypes that are molecularly related to haplotypes found in other African Bantu‐speaking populations. The putatively archaic G3 variant displayed more intra‐allelic diversity in Africa than in Europe. Discussion: The LP adaptation was carried to southern Africa by non‐Bantu speaking pastoralists from eastern Africa, but an obvious link between its presence in southern Angola and groups speaking languages of the Khoe‐Kwadi family, as previously found in other areas, could not be confirmed. The presence of APOL1 variants G1 and G2 is linked to the Bantu expansions. Our results suggest that the G3 variant was retained in modern humans by incomplete lineage sorting.

  July 12, 2016   doi: 10.1002/ajpa.23042   open full text
• Comparing primate crania: The importance of fossils.
  John G. Fleagle, Christopher C. Gilbert, Andrea L. Baden.
  American Journal of Physical Anthropology. July 12, 2016
  Objectives Extant primate crania represent a small subset of primate crania that have existed. The main objective here is to examine how the inclusion of fossil crania changes our understanding of primate cranial diversity relative to analyses of extant primates. We hypothesize that fossil taxa will change the major axes of cranial shape, occupy new areas of morphospace, change the relative diversity of major primate clades, and fill in notable gaps separating major primate taxa/clades. Materials and Methods Eighteen 3D landmarks were collected on 157 extant and fossil crania representing 90 genera. Data were subjected to a Generalized Procrustes Analysis then principal components analysis. Relative diversity between clades was assessed using an F‐statistic. Results Fossil taxa do not significantly alter major axes of cranial shape, but they do occupy unique areas of morphospace, change the relative diversity between clades, and fill in notable gaps in primate cranial evolution. Strepsirrhines remain significantly less diverse than anthropoids. Fossil hominins fill the gap in cranial morphospace between extant great apes and modern humans. Discussion The morphospace outlined by living primates largely includes that occupied by fossil taxa, suggesting that the cranial diversity of living primates generally encompasses the total diversity that has evolved in this Order. The evolution of the anthropoid cranium was a significant event allowing anthropoids to achieve significantly greater cranial diversity compared to strepsirrhines. Fossil taxa fill in notable gaps within and between clades, highlighting their transitional nature and eliminating the appearance of large morphological distances between extant taxa, particularly in the case of extant hominids.

  July 12, 2016   doi: 10.1002/ajpa.23026   open full text
• The apportionment of tooth size and its implications in Australopithecus sediba versus other Plio‐pleistocene and recent African hominins.
  Joel D. Irish, Brian E. Hemphill, Darryl J. de Ruiter, Lee R. Berger.
  American Journal of Physical Anthropology. July 12, 2016
  Objectives Australopithecus sediba is characterized further by providing formerly unpublished and refined mesiodistal and buccolingual crown measurements in the MH1 and MH2 specimens. After size correction, these data were compared with those in other fossil and recent samples to facilitate additional insight into diachronic hominin affinities. Materials and Methods Six comparative samples consist of fossil species: A. africanus, A. afarensis, Homo habilis, Paranthropus robustus, P. boisei, and H. erectus. Others comprise H. sapiens and Pan troglodytes. Re‐estimates of “actual” dimensions in damaged A. sediba teeth were effected through repeated measurements by independent observers. X‐ray synchrotron microtomography allowed measurement of crowns obscured by matrix and noneruption. Tooth size apportionment analysis, an established technique for intraspecific comparisons, was then applied at this interspecific level to assess phenetic affinities using both within‐ and among‐group data. Results Comparison of these highly heritable dimensions identified a general trend for smaller posterior relative to larger anterior teeth (not including canines), contra Paranthropus, that allies A. sediba with other australopiths and Homo; however, specific reductions and/or shape variation in the species’ canines, third premolars, and anterior molars relative to the other teeth mirror the patterning characteristic of Homo. Discusssion Of all samples, including east African australopiths, A. sediba appears most like H. habilis, H. erectus and H. sapiens regarding how crown size is apportioned along the tooth rows. These findings parallel those in prior studies of dental and other skeletal data, including several that suggest A. sediba is a close relative of, if not ancestral to, Homo.

  July 12, 2016   doi: 10.1002/ajpa.23039   open full text
• Tracing residential mobility during the Merovingian period: An isotopic analysis of human remains from the Upper Rhine Valley, Germany.
  Christine Schuh, Cheryl A. Makarewicz.
  American Journal of Physical Anthropology. July 12, 2016
  Objectives Written sources have provided information about the rise of Merovingian power and their territorial conquests after the disintegration of the Western Roman Empire, but the extent to which altered power relations in the newly annexed territories reshaped regional and local communities is poorly understood. The early medieval cemetery of Dirmstein, located in the Upper Rhine Valley, is one of the rare sites bearing archeological evidence of simultaneous use by an indigenous community and newcomers from outside the Merovingian core area, and it offers the opportunity to investigate residential mobility at the former Roman Rhine frontier during the Merovingian period. Materials and Methods We conducted strontium, oxygen, and carbon isotope analyses on human tooth enamel recovered from 25 sixth century inhumations at the Dirmstein cemetery to establish the presence of newcomers to the Upper Rhine region. Results The low δ13C values exhibited by the Dirmstein individuals revealed ingestion of a C3 terrestrial based diet, with no detectable contribution of C4 plants, which indicates the absence of individuals from regions where a C4‐based diet was common. Human 87Sr/86Sr values well outside the local range of bioavailable strontium, in combination with low δ18O values, suggest a notable presence of newcomers from more eastern or high altitude regions. Conclusions The isotopic evidence indicates that residential mobility was important and new settlers, most likely from outside the Merovingian core area, contributed to the settlement of the northern Upper Rhine Valley during the sixth century AD.

  July 12, 2016   doi: 10.1002/ajpa.23017   open full text
• Morphological convergence in the pubis of slow‐moving primates and xenarthrans.
  Kristi L. Lewton, Heather L. Dingwall.
  American Journal of Physical Anthropology. July 05, 2016
  Objectives Determining the functional significance of pubic rami is important for reconstructing locomotor behavior of fossil species. The slow loris pelvis, characterized by long pubic rami, is unusual among primates. Long pubic rami may be related to increasing the moment arm of the abdominal musculature during ventroflexion after the termination of hindlimb suspension, which is a common component of slow arboreal quadrupedalism (AQ). Some extant xenarthran species are also slow AQ taxa, and provide an ideal group to test hypotheses of morphologically convergent adaptations to slow AQ. Materials and Methods A model relating abdominal moment arms to pubic morphology is tested in three genera of slow‐moving xenarthrans (Bradypus, Choloepus, and Cyclopes) and two species of slow loris (Nycticebus coucang and Perodicticus potto), using a comparative sample of 37 species of primates and xenarthrans. Phylogenetic analyses of variance and regression were performed on pubic dimensions (superior and inferior pubic ramus length, pubic symphysis length). Results As a locomotor group, slow‐moving xenarthrans and lorises share superior pubic rami that are longer than all other locomotor groups; at the species level, there is some overlap among slow AQ and non‐slow‐AQ taxa. Inferior pubic ramus and pubic symphysis lengths also differ according to locomotor category, but multiple comparisons among locomotor groups are non‐significant. Discussion These results support the hypothesis that superior pubic ramus length is functionally related to slow, suspensory locomotion by increasing the leverage of the ventral abdominal musculature, and demonstrates morphological convergence among two phylogenetically distant groups of mammals that have evolved adaptations for slow, suspensory locomotion.

  July 05, 2016   doi: 10.1002/ajpa.23038   open full text
• High resting metabolic rate among Amazonian forager‐horticulturalists experiencing high pathogen burden.
  Michael D. Gurven, Benjamin C. Trumble, Jonathan Stieglitz, Gandhi Yetish, Daniel Cummings, Aaron D. Blackwell, Bret Beheim, Hillard S. Kaplan, Herman Pontzer.
  American Journal of Physical Anthropology. July 04, 2016
  Objectives Resting metabolic rate (RMR) reflects energetic costs of homeostasis and accounts for 60 to 75% of total energy expenditure (TEE). Lean mass and physical activity account for much RMR variability, but the impact of prolonged immune activation from infection on human RMR is unclear in naturalistic settings. We evaluate the effects of infection on mass‐corrected RMR among Bolivian forager‐horticulturalists, and assess whether RMR declines more slowly with age than in hygienic sedentary populations, as might be expected if older adults experience high pathogen burden. Materials and Methods RMR was measured by indirect calorimetry (Fitmate MED, Cosmed) in 1,300 adults aged 20 to 90 and TEE was measured using doubly labeled water (n = 40). Immune biomarkers, clinical diagnoses, and anthropometrics were collected by the Tsimane Health and Life History Project. Results Tsimane have higher RMR and TEE than people in sedentary industrialized populations. Tsimane RMR is 18 to 47% (women) and 22 to 40% (men) higher than expected using six standard prediction equations. Tsimane mass‐corrected TEE is similarly elevated compared to Westerners. Elevated leukocytes and helminths are associated with excess RMR in multivariate regressions, and jointly result in a predicted excess RMR of 10 to 15%. After age 40, RMR declines by 69 kcal/decade (p < .0001). Controlling for lean mass and height accounts for 71% of age‐related RMR decline, and adding indicators of infection minimally affects the age slope. The residual level of age‐related decline from age 40 is 1.2% per decade. Conclusion High pathogen burden may lead to higher metabolic costs, which may be offset by smaller body mass or other energy‐sparing mechanisms.

  July 04, 2016   doi: 10.1002/ajpa.23040   open full text
• Absolute humidity and the human nose: A reanalysis of climate zones and their influence on nasal form and function.
  Scott D. Maddux, Todd R. Yokley, Bohumil M. Svoma, Robert G. Franciscus.
  American Journal of Physical Anthropology. July 04, 2016
  Objectives Investigations into the selective role of climate on human nasal variation commonly divide climates into four broad adaptive zones (hot‐dry, hot‐wet, cold‐dry, and cold‐wet) based on temperature and relative humidity. Yet, absolute humidity—not relative humidity—is physiologically more important during respiration. Here, we investigate the global distribution of absolute humidity to better clarify ecogeographic demands on nasal physiology. Methods We use monthly observations from the Climatic Research Unit Timeseries 3 (CRU TS3) database to construct global maps of average annual temperature, relative humidity and absolute humidity. Further, using data collected by Thomson and Buxton (1923) for over 15,000 globally‐distributed individuals, we calculate the actual amount of heat and water that must be transferred to inspired air in different climatic regimes to maintain homeostasis, and investigate the influence of these factors on the nasal index. Results Our results show that absolute humidity, like temperature, generally decreases with latitude. Furthermore, our results demonstrate that environments typically characterized as “cold‐wet” actually exhibit low absolute humidities, with values virtually identical to cold‐dry environments and significantly lower than hot‐wet and even hot‐dry environments. Our results also indicate that strong associations between the nasal index and absolute humidity are, potentially erroneously, predicated on individuals from hot‐dry environments possessing intermediate (mesorrhine) nasal indices. Discussion We suggest that differentially allocating populations to cold‐dry or cold‐wet climates is unlikely to reflect different selective pressures on respiratory physiology and nasal morphology—it is cold‐dry, and to a lesser degree hot‐dry environments, that stress respiratory function. Our study also supports assertions that demands for inspiratory modification are reduced in hot‐wet environments, and that expiratory heat elimination for thermoregulation is a greater selective pressure in such environments.

  July 04, 2016   doi: 10.1002/ajpa.23032   open full text
• Oral microbiome diversity among Cheyenne and Arapaho individuals from Oklahoma.
  Andrew T. Ozga, Krithivasan Sankaranarayanan, Raúl Y. Tito, Alexandra J. Obregon‐Tito, Morris W. Foster, Gloria Tallbull, Paul Spicer, Christina G. Warinner, Cecil M. Lewis.
  American Journal of Physical Anthropology. June 30, 2016
  Objectives There is a major ascertainment bias in microbiome research, with individuals of predominately European ancestry living within metropolitan areas dominating most studies. Here we present a study of the salivary microbiome within a North American Indian community. This research is the culmination of four years of collaboration and community engagement with Cheyenne & Arapaho (C&A) tribal members from western Oklahoma. Materials and Methods Using 16S rRNA gene amplification and next‐generation sequencing, we generated microbial taxonomic inventories for 37 individuals representing five towns within the C&A tribes. For comparison, we performed the same laboratory techniques on saliva samples from 20 non‐native individuals (NNI) from Norman, Oklahoma. Results The C&A participants differ from the NNI in having reduced within‐individual species richness and higher between‐individual variation. Unsupervised clustering analyses reveal that three ecological groupings best fit the data, and while C&A individuals include assignments to all three groups, the NNI individuals are assigned to only one group. One of the ecological groups found exclusively among C&A participants was characterized by high abundance of the oral bacterial genus Prevotella. Discussion The C&A and NNI participants from Oklahoma have notable differences in their microbiome diversity, with a wider range of variation observed among the C&A individuals, including a higher frequency of bacteria implicated in systemic disorders. Overall, this study highlights the importance of engagement with indigenous communities, and the need for an improved understanding of human microbiome diversity among underrepresented groups and those individuals living outside of metropolitan areas.

  June 30, 2016   doi: 10.1002/ajpa.23033   open full text
• Testing the equivalence of modern human cranial covariance structure: Implications for bioarchaeological applications.
  Noreen von Cramon‐Taubadel, Lauren Schroeder.
  American Journal of Physical Anthropology. June 30, 2016
  Objectives Estimation of the variance‐covariance (V/CV) structure of fragmentary bioarchaeological populations requires the use of proxy extant V/CV parameters. However, it is currently unclear whether extant human populations exhibit equivalent V/CV structures. Materials and Methods Random skewers (RS) and hierarchical analyses of common principal components (CPC) were applied to a modern human cranial dataset. Cranial V/CV similarity was assessed globally for samples of individual populations (jackknifed method) and for pairwise population sample contrasts. The results were examined in light of potential explanatory factors for covariance difference, such as geographic region, among‐group distance, and sample size. Results RS analyses showed that population samples exhibited highly correlated multivariate responses to selection, and that differences in RS results were primarily a consequence of differences in sample size. The CPC method yielded mixed results, depending upon the statistical criterion used to evaluate the hierarchy. The hypothesis‐testing (step‐up) approach was deemed problematic due to sensitivity to low statistical power and elevated Type I errors. In contrast, the model‐fitting (lowest AIC) approach suggested that V/CV matrices were proportional and/or shared a large number of CPCs. Pairwise population sample CPC results were correlated with cranial distance, suggesting that population history explains some of the variability in V/CV structure among groups. Discussion The results indicate that patterns of covariance in human craniometric samples are broadly similar but not identical. These findings have important implications for choosing extant covariance matrices to use as proxy V/CV parameters in evolutionary analyses of past populations.

  June 30, 2016   doi: 10.1002/ajpa.23037   open full text
• Bone remodeling is reduced in high stress regions of the cercopithecoid mandible.
  Susan E. Lad, David J. Daegling, W. Scott McGraw.
  American Journal of Physical Anthropology. June 27, 2016
  Objectives Independent lines of evidence suggest that osteonal bone remodeling is a function of both mechanical (i.e., changes in stress) and non‐mechanical (i.e., metabolic needs related to calcium liberation) factors. The degree to which secondary bone reflects mechanical factors, however, is incompletely understood despite the common assumption that the stress environment mediates remodeling activity. Here, we investigate whether there are remodeling differences between regions of primate mandibular bone known to have distinct stress environments. Methods Osteon density, osteon fragment density, and relative osteonal area are measured as indicators of remodeling activity from postcanine and symphyseal thin sections of four sympatric monkey species (N = 20 total) from Taï Forest, Côte dʼIvoire: Piliocolobus badius, Colobus polykomos, Cercocebus atys, Cercopithecus diana. Subfamily and regional effects were assessed by two‐way ANOVA. Results Symphyseal bone has lower osteonal density, fragment density and relative osteonal area than postcanine bone in all species, indicating relatively low remodeling activity in symphyseal bone, despite the likelihood of relatively high stresses in its lingual cortex. Subfamily differences in postcanine remodeling are significant in that colobines exhibit greater remodeling than cercopithecines. Discussion The data suggest that high strains are not requisite for bone remodeling. How the lingual symphysis negotiates a high strain environment without the reparative benefit of remodeling is yet to be elucidated, but the data prompt reevaluation of the relationship of targeted remodeling to stress histories. Differences in osteonal bone density between taxa might reflect feeding or dietary influences on remodeling activity, but sample composition prevents parsing behavioral from other taxon‐specific effects.

  June 27, 2016   doi: 10.1002/ajpa.23041   open full text
• Determinants of terrestrial feeding in an arboreal primate: The case of the southern bamboo lemur (Hapalemur meridionalis).
  Timothy M. Eppley, Giuseppe Donati, Jörg U. Ganzhorn.
  American Journal of Physical Anthropology. June 27, 2016
  Objectives The proximate and ultimate determinants that may have prompted some primates to shift from an arboreal to terrestrial feeding niche, whether due to environmental change, seasonality, and/or predation pressure, are poorly understood. Within a fragmented littoral forest in southeast Madagascar, an arboreal strepsirrhine population spends a large proportion of time on the ground, thus we aimed to identify which factors influence terrestrial feeding. Methods From January to December 2013, we conducted 103 full‐day focal follows on three social groups of southern bamboo lemurs H. meridionalis. We continuously recorded feeding time on all arboreal and terrestrial items, as well as whether the focal individual was under the canopy or exposed, and the distance to their nearest conspecific neighbor. All observed food items were collected and analyzed for macronutrient content. Daily climatic variables (temperature, precipitation), resource seasonality, daily path length (DPL), along with dietary and predation risk proxies, were used as fixed effects in a linear mixed model, with the daily proportion of terrestrial feeding as the dependent variable. Results Our model indicated that daily terrestrial feeding increased at cooler temperature, was associated with reduced DPL, and the intake of dietary metabolizable energy increased as terrestrial feeding increased. All other fixed effects were not significant predictors. Discussion Our study provides a window into the ultimate determinants of niche expansion: ancestral primates, in absence of their primary resources, may have initially descended to the ground in peripheral population range areas where the benefits (e g., nutritional pay‐off) out‐weighed the costs.

  June 27, 2016   doi: 10.1002/ajpa.23034   open full text
• The role of leaf toughness on foraging efficiency in Angola black and white colobus monkeys (Colobus angolensis palliatus).
  Noah T. Dunham, Alexander L. Lambert.
  American Journal of Physical Anthropology. June 27, 2016
  Objectives Examining the relationships among foraging behavior, food mechanical properties, and masticatory morphology is a bourgeoning research topic among behavioral ecologists and functional morphologists. The purpose of this study was to assess the degree to which leaf toughness influences foraging efficiency with regard to ingestion rate, masticatory investment, and masticatory rate. Methods Diet and feeding data were collected on adults from three groups of Colobus angolensis palliatus in the Diani Forest, Kenya, from July 2014 to December 2015. Ingestion rates were estimated by counting the number of items consumed during feeding bouts and multiplying this value by the mean mass of a particular food item. The number of mastications was also counted during 3–5 minute focal periods. Mechanical toughness of commonly eaten young leaves (n = 27 species) and mature leaves (n = 13 species) was recorded using a toughness tester equipped with a razor blade. Results Ingestion rates (g/min) negatively correlated with leaf toughness (r2 = 0.73; p < 0.01) while masticatory investment (chews/g) positively correlated with leaf toughness (r2 = 0.72; p < 0.01). Chewing rate (chews/min) was remarkably consistent regardless of leaf species and toughness values (r2 = 0.09; p = 0.07). Discussion Our findings highlight the degree to which toughness values can vary among leaves and how this variation can dramatically influence ingestion rates and chewing efficiency in black and white colobus monkeys. Studies that link food mechanical properties with oral processing behaviors will ultimately provide important context for understanding craniofacial and dentognathic traits in primates.

  June 27, 2016   doi: 10.1002/ajpa.23036   open full text
• Spatial determinants of the mandibular curve of Spee in modern and archaic Homo.
  Myra F. Laird, Nathan E. Holton, Jill E. Scott, Robert G. Franciscus, Steven D. Marshall, Thomas E. Southard.
  American Journal of Physical Anthropology. June 27, 2016
  Objectives The curve of Spee (COS) is a mesio‐distally curved alignment of the canine through distal molar cusp tips in certain mammals including modern humans and some fossil hominins. In humans, the alignment varies from concave to flat, and previous studies have suggested that this difference reflects craniofacial morphology, including the degree of alveolar prognathism. However, the relationship between prognathism and concavity of the COS has not been tested in craniofacially variant populations. We tested the hypothesis that greater alveolar prognathism covaries with a flatter COS in African‐American and European‐American populations. We further examined this relationship in fossil Homo including Homo neanderthalensis and early anatomically modern Homo sapiens, which are expected to extend the amount of variation in the COS from the extant sample. Methods and Materials These hypotheses were tested using three‐dimensional geometric morphometrics. Landmarks were recorded from the skulls of 166 African‐Americans, 123 European‐Americans, and 10 fossil hominin mandible casts. Landmarks were subjected to generalized Procrustes analysis, principal components analysis, and two‐block partial least squares analysis. Results We documented covariation between the COS and alveolar prognathism such that relatively prognathic individuals have a flatter COS. Mandibular data from the fossil hominin taxa generally confirm and extend this correlation across a greater range of facial size and morphology in Homo. Discussion Our results suggest that the magnitude of the COS is related to a suite of features associated with alveolar prognathism in modern humans and across anthropoids. We also discuss the implications for spatial interactions between the dental arches.

  June 27, 2016   doi: 10.1002/ajpa.23020   open full text
• Maximum likelihood estimate of life expectancy in the prehistoric Jomon: Canine pulp volume reduction suggests a longer life expectancy than previously thought.
  Tomohiko Sasaki, Osamu Kondo.
  American Journal of Physical Anthropology. June 27, 2016
  Recent theoretical progress potentially refutes past claims that paleodemographic estimations are flawed by statistical problems, including age mimicry and sample bias due to differential preservation. The life expectancy at age 15 of the Jomon period prehistoric populace in Japan was initially estimated to have been ∼16 years while a more recent analysis suggested 31.5 years. In this study, we provide alternative results based on a new methodology. The material comprises 234 mandibular canines from Jomon period skeletal remains and a reference sample of 363 mandibular canines of recent‐modern Japanese. Dental pulp reduction is used as the age‐indicator, which because of tooth durability is presumed to minimize the effect of differential preservation. Maximum likelihood estimation, which theoretically avoids age mimicry, was applied. Our methods also adjusted for the known pulp volume reduction rate among recent‐modern Japanese to provide a better fit for observations in the Jomon period sample. Without adjustment for the known rate in pulp volume reduction, estimates of Jomon life expectancy at age 15 were dubiously long. However, when the rate was adjusted, the estimate results in a value that falls within the range of modern hunter‐gatherers, with significantly better fit to the observations. The rate‐adjusted result of 32.2 years more likely represents the true life expectancy of the Jomon people at age 15, than the result without adjustment. Considering ∼7% rate of antemortem loss of the mandibular canine observed in our Jomon period sample, actual life expectancy at age 15 may have been as high as ∼35.3 years.

  June 27, 2016   doi: 10.1002/ajpa.23018   open full text
• Grasping primate development: Ontogeny of intrinsic hand and foot proportions in capuchin monkeys (Cebus albifrons and Sapajus apella).
  Jesse W. Young, Amber N. Heard‐Booth.
  American Journal of Physical Anthropology. June 21, 2016
  Young primates have relatively large hands and feet for their body size, perhaps enhancing grasping ability. We test the hypothesis that selection for improved grasping ability is responsible for these scaling trends by examining the ontogeny of intrinsic hand and foot proportions in capuchin monkeys (Cebus albifrons and Sapajus apella). If selection for improved grasping ability is responsible for the observed patterns of hand and foot growth in primates, we predicted that fingers and toes would be longer early in life and proportionally decline with age. We measured the lengths of manual and pedal metapodials and phalanges in a mixed‐longitudinal radiographic sample. Bone lengths were (a) converted into phalangeal indices (summed non‐distal phalangeal length/metapodial length) to test for age‐related changes in intrinsic proportions and (b) fit to Gompertz models of growth to test for differences in the dynamics of phalangeal versus metapodial growth. Manual and pedal phalangeal indices nearly universally decreased with age in capuchin monkeys. Growth curve analyses revealed that metapodials generally grew at a faster rate, and for a longer duration, than corresponding phalanges. Our findings are consistent with the hypothesis that primates are under selection for increased grasping ability early in life. Relatively long digits may be functionally adaptive for growing capuchins, permitting a more secure grasp on both caregivers and arboreal supports, as well as facilitating early foraging. Additional studies of primates and other mammals, as well as tests of grasping performance, are required to fully evaluate the adaptive significance of primate hand and foot growth.

  June 21, 2016   doi: 10.1002/ajpa.23013   open full text
• Turning the tables of sex distinction in craniofacial identification: Why females possess thicker facial soft tissues than males, not vice versa.
  Carl N. Stephan, Rory Preisler, Ozgur Bulut, Mike Bennett.
  American Journal of Physical Anthropology. June 21, 2016
  Males are universally reported to possess larger facial soft‐tissue thickness (FSTT) than females, however, this observation oversimplifies the raw data yielding an underpowered assessment of FSTT sex‐patterning where: differences are small (η2 < 5%) and inconsistent (females are routinely larger than males at the cheeks). Here we investigate body‐size normalized data to assess whether more general and improved understanding of FSTT sex‐variation in humans is possible. FSTTs were measured in 52 healthy living Australians aged 18 to 30 years using B‐mode ultrasound. Participants' stature and body mass were also measured. Sex differences were calculated before and after normalization by the aforementioned body‐composition variables. Methods were repeated in three other independent samples to evaluate reproducibility: 100 American Whites and 60 American Blacks measured by B‐mode ultrasound; and 50 Turkish residents measured by regular supine CT. Compared to raw mean differences (F < M, by −6%), females displayed much thicker FSTTs than males when normalized for body mass (F > M, by +16%). Consequently, while the sexes share similar raw values, females possess much larger FSTTs for their relatively lighter bodies. The relative FSTT difference was 2.7× larger than the raw mean difference. Sex differences in FSTT are of larger magnitude and reversed direction in mass normalized data. Contrary to popular thought, females possess much larger FSTTs than males owing to their generically lighter bodies (−18 kg). These data patterns help explain why the pooling of sex‐categorized FSTT does not jeopardize the sex‐difference—it is encoded more strongly in terms relative to body mass.

  June 21, 2016   doi: 10.1002/ajpa.23029   open full text
• Constructing cranial ontogenetic trajectories: A comparison of growth, development, and chronological age proxies using a known‐age sample of Macaca mulatta.
  Evan A. Simons, Stephen R. Frost.
  American Journal of Physical Anthropology. June 21, 2016
  Recent morphometric research has generated opposing conclusions regarding the ontogenetic trajectories of catarrhine crania, possibly due to the ontogenetic proxies used to calculate them. Therefore, we used three surrogates: size, molar eruption, and chronological age to generate trajectories in a known‐age sample to produce ontogenetic trajectories and determine the similarities and differences between them. Forty‐three landmarks from an ontogenetic series of 160 Macaca mulatta crania, with associated ages at death, were used to produce ontogenetic trajectories of cranial shape change. These were computed by sex through multivariate regression of Procrustes aligned coordinates against three surrogates for ontogeny: natural log of centroid size (growth), molar eruption stage (development), and chronological age. These trajectories were compared by calculating the angles between them. Each trajectory was also used to produce simulated adults from juveniles, which were then compared with each other and actual adults. The different trajectories are nearly parallel as each of the surrogates track similar aspects of ontogenetic cranial shape change, but chronological age was the most divergent. Simulated adults produced using the developmental stage trajectories were most similar to actual adults. When simulated adults were produced from opposite sex trajectories, they resembled the sex from which the trajectory was produced, not the sex of the juvenile specimen. We discuss properties of the trajectories produced from each of the surrogates, the possible reasons for previously opposing conclusions, how these properties can inform future investigations, and how our investigation bears on analyses of heterochrony.

  June 21, 2016   doi: 10.1002/ajpa.23031   open full text
• Lower molar shape and size in prosimian and platyrrhine primates.
  Elizabeth M. St. Clair, Doug M. Boyer.
  American Journal of Physical Anthropology. June 17, 2016
  The goal of this research is to evaluate the relative strength of the influences of diet, size, and phylogenetic signal on dental geometric shape. Accurate comprehension of these factors and their interaction is important for reconstructing diet and deriving characters for a cladistic analysis in fossil primates. Geometric morphometric analysis is used to identify axes of shape variation in the lower second molars of (a) prosimian primates and (b) platyrrhines. Landmarks were placed on µCT‐generated surface renderings. Landmark configurations were aligned using generalized Procrustes analysis. Principal components analysis and phylogenetic principal components analysis (pPCA) were performed on species average landmark co‐ordinates. pPCs were examined with phylogenetic generalized least squares analysis for association with size and with diet. PCs from both phylogenetic and non‐phylogenetic analyses were sufficient to separate species by broad dietary categories, including insectivores and folivores. In neither analysis was pPC1 correlated with tooth size, but some other pPCs were significantly correlated with size. The pattern of association between pPCs and size altered when centroid size and dietary variables were combined in the model; effects of diet factors typically exceeded effects of size. These results indicate a dominant phylogenetic and dietary signal in molar shape but also show some shape change correlated with size in the absence of obvious dietary associations. Geometric morphometric analysis appears to be useful for tracking functional traits in molars, particularly in tracking differences between folivorous and insectivorous species.

  June 17, 2016   doi: 10.1002/ajpa.23021   open full text
• In sickness and in death: Assessing frailty in human skeletal remains.
  Kathryn E. Marklein, Rachael E. Leahy, Douglas E. Crews.
  American Journal of Physical Anthropology. June 17, 2016
  Stress plays an important role in the etiology of multiple morbid and mortal outcomes among the living. Drawing on health paradigms constructed among the living augments our evolving knowledge of relationships between stress and health. Therefore, elucidating relationships between stress and both chronic and acute skeletal lesions may help clarify our understanding of long‐term health trends in the past. In this study, we propose an index of “skeletal frailty,” based on models of frailty used to evaluate the life‐long effects of stress on health among living populations. Here, we assess the possible applicability of frailty to archaeological populations. The skeletal frailty index (SFI) is proposed as a methodological liaison between advances made by biological anthropologists studying relationships between stress and health among the living and bioarchaeologists studying stress and health among the dead. In a case study examining skeletal stress in Medieval London, the SFI is applied to nonmonastic (N = 60) and monastic (N = 74) samples. We used analysis of variance/analysis of covariance to compare SFI values between nonmonastic‐monastic groups, sexes, and age cohorts. Results indicate higher lifetime morbidity among monastic groups. These results complement previous bioarchaeological findings on the same London populations, wherein lower risks of mortality and longer lifespans were observed for monastic populations. SFI data reflect the morbidity‐mortality paradox observed in modern populations and accompany recent findings in bioarchaeology of variation in Medieval monastic and nonmonastic “health.” Ultimately, this study demonstrates the SFI's utility in bioarchaeology, through its application of commonly assessed skeletal biomarkers, its ease of applicability, and its potential usefulness for assessing changes in skeletal health over time and across specific geographies.

  June 17, 2016   doi: 10.1002/ajpa.23019   open full text
• Fringes of the empire: Diet and cultural change at the Roman to post‐Roman transition in NW Iberia.
  Olalla López‐Costas, Gundula Müldner.
  American Journal of Physical Anthropology. June 17, 2016
  A growing number of paleodiet investigations over recent years have begun to reveal the stark dietary differences that existed between regions of the Roman Empire, as well as significant changes in subsistence strategies after its fall. The present study explores the dietary changes at the Roman to post‐Roman (Germanic) transition in the Northwest Iberian Peninsula, in order to improve our understanding of the changes that occurred at end of the Roman Empire in different regions across Europe and to also consider the influence of climate had on them. The carbon and nitrogen stable isotope investigation in bone collagen from A Lanzada, NW Spain (100–700 AD), which was an important commercial, coastal settlement has been presented. A human sample of 59 individuals, 6 of them subadults, is compared with 31 faunal specimens, which include a number of marine fish. Isotope data for the terrestrial fauna reveal the influence of the sea on the local isotope baseline. Analysis of the human samples indicates a mixed marine‐terrestrial diet. A shift in mean human δ13C values from −16.7‰ to −14.3‰ provides clear evidence for a significant change in diet in the post‐Roman period, probably through the intensification of both marine resources exploitation and C4‐plant consumption (presumably millet). A deterioration of paleoenvironmental conditions, together with a poor socioeconomic situation and the arrival of new people, the Sueves, who brought a new political and socioeconomic system have been discussed as the main causes for the dietary modification in post‐Roman times.

  June 17, 2016   doi: 10.1002/ajpa.23016   open full text
• Behavioral and functional strategies during tool use tasks in bonobos.
  Ameline Bardo, Antony Borel, Hélène Meunier, Jean‐Pascal Guéry, Emmanuelle Pouydebat.
  American Journal of Physical Anthropology. June 17, 2016
  Different primate species have developed extensive capacities for grasping and manipulating objects. However, the manual abilities of primates remain poorly known from a dynamic point of view. The aim of the present study was to quantify the functional and behavioral strategies used by captive bonobos (Pan paniscus) during tool use tasks. The study was conducted on eight captive bonobos which we observed during two tool use tasks: food extraction from a large piece of wood and food recovery from a maze. We focused on grasping postures, in‐hand movements, the sequences of grasp postures used that have not been studied in bonobos, and the kind of tools selected. Bonobos used a great variety of grasping postures during both tool use tasks. They were capable of in‐hand movement, demonstrated complex sequences of contacts, and showed more dynamic manipulation during the maze task than during the extraction task. They arrived on the location of the task with the tool already modified and used different kinds of tools according to the task. We also observed individual manual strategies. Bonobos were thus able to develop in‐hand movements similar to humans and chimpanzees, demonstrated dynamic manipulation, and they responded to task constraints by selecting and modifying tools appropriately, usually before they started the tasks. These results show the necessity to quantify object manipulation in different species to better understand their real manual specificities, which is essential to reconstruct the evolution of primate manual abilities.

  June 17, 2016   doi: 10.1002/ajpa.23015   open full text
• Agerinia smithorum sp. nov., a new early Eocene primate from the Iberian Peninsula.
  Joan Femenias‐Gual, Raef Minwer‐Barakat, Judit Marigó, Salvador Moyà‐Solà.
  American Journal of Physical Anthropology. June 16, 2016
  The new species Agerinia smithorum (Adapiformes, Primates) from the early Eocene of the Iberian Peninsula is erected in this work. An emended diagnosis of the genus is provided, together with a broad description of the new species and comparisons with other samples assigned to Agerinia and other similar medium‐sized cercamoniines. The new species is based on the most complete specimen of this genus published to date, a mandible preserving the alveoli of the canine and P1, the roots of the P2 and all teeth from P3 to M3. It was found in Casa Retjo‐1, a new early Eocene locality from Northeastern Spain. The studied specimen is clearly distinguishable from other cercamoniines such as Periconodon, Darwinius, and Donrussellia, but very similar to Agerinia roselli, especially in the similar height of P3 and P4 and the general morphology of the molars, therefore allowing the allocation to the same genus. However, it is undoubtedly distinct from A. roselli, having a less molarized P4 and showing a larger paraconid in the M1 and a tiny one in the M2, among other differences. The body mass of A. smithorum has also been estimated, ranging from 652 to 724 g, similar to that of A. roselli. The primitive traits shown by A. smithorum (moderately molarized P4, large paraconid in the M1 and small but distinct in the M2) suggest that it could be the ancestor of A. roselli.

  June 16, 2016   doi: 10.1002/ajpa.23014   open full text
• Sexual dimorphism in growth in the relative length of the forearm and relative knee height during adolescence.
  Natalia Nowak‐Szczepanska, Slawomir Koziel.
  American Journal of Physical Anthropology. June 13, 2016
  There are numerous studies concerning sexual dimorphism in body proportions, but only a few have investigated growth in the relative length of particular segments of the upper and lower limbs during adolescence. The aim of the study is an assessment of sex differences of longitudinal growth in the relative length of the forearm and knee height among adolescents. Sample involved 121 boys and 111 girls, participants of the Wroclaw Growth Study, examined annually between 8 and 18 years of age. Sexual dimorphism in six ratios: forearm length and knee height relatively to: trunk, height, and limb length were analyzed using a two‐way analysis of variance with repeated measurements. The sex and age relative to an estimate of maturity timing (3 years before, and after age class at peak height velocity [PHV]) were independent variables. All of the ratios showed significant sex differences in interaction with age relative to age at PHV. The relative length of the forearm, in boys, did not change significantly with the years relative to age at PHV, whereas in girls, was the lowest in the two first age classes and afterward significantly increased just 1 year before and during the adolescent growth spurt, remaining unchanged in further age classes. For relative knee height no clear pattern for sex differences was noticed. It is proposed that relatively longer forearms, particularly in relation to the trunk in girls, could have evolved as an adaptation to more efficient infant carrying and protection during breastfeeding.

  June 13, 2016   doi: 10.1002/ajpa.23028   open full text
• Intracemetery biological variation at the fort ancient sunwatch village.
  Paul W. Sciulli, Robert A. Cook.
  American Journal of Physical Anthropology. June 06, 2016
  Objectives We investigate intracemetery biological variation at the Fort Ancient SunWatch village (800–500 BP.) to test the hypothesis that the SunWatch population consisted of spatially structured biologically differentiated kin groups consisting of distinct local Late Woodland and non‐local Mississippian biological populations. Material and Methods The SunWatch sample contains 166 individuals: 63 adults and 103 subadults. We analyze intracemetery biological variation using two feature sets: the buccolingual diameters of the polar teeth in the permanent (n = 37) and deciduous (n = 26) dentitions. We apply matrix correlation models to biodistance and grave distance matrices in both data sets, evaluate burial outliers and individuals exhibiting a rare dental feature with interindividual biological distances, and evaluate potential cultural subgroups with Mahalanobis' distance. Results Matrix correlation analyses for both feature sets as well as interindividual and subgroup distances indicate the SunWatch village cemetery was kin structured, contained a single primary biological population, and also contained a small number of non‐local individuals most of whom were from closely related populations. We thus reject the hypothesis that the SunWatch population consisted of biologically distinct Late Woodland and Mississippian biological populations. Discussion Although SunWatch village exhibited cultural attributes characteristic of both local Late Woodland and non‐local Mississippian groups, biologically the village was composed of one primary population. The lack of evidence for marked biological differentiation in the SunWatch village area at about 800–500 BP. suggests diffusion and acculturation may account for Mississippian cultural characteristics in southwestern Ohio Fort Ancient villages. If gene flow or migrations from biologically distinct Mississippian populations into southwestern Ohio occurred, either or both likely occurred well before 800 BP. This would have allowed the process of admixture time to produce a relatively homogeneous, nondifferentiated population. The latter alternative is consistent with the appearance in southwestern Ohio of non‐local individuals at one site linked to surrounding Mississippian regions at about 950 BP. Am J Phys Anthropol 160:719–728, 2016. © 2016 Wiley Periodicals, Inc.

  June 06, 2016   doi: 10.1002/ajpa.23001   open full text
• Ontogenetic scaling of fore limb and hind limb joint posture and limb bone cross‐sectional geometry in vervets and baboons.
  M. Loring Burgess, Daniel Schmitt, Angel Zeininger, Shannon C. McFarlin, Adrienne L. Zihlman, John D. Polk, Christopher B. Ruff.
  American Journal of Physical Anthropology. June 02, 2016
  Objectives Previous studies suggest that the postures habitually adopted by an animal influence the mechanical loading of its long bones. Relatively extended limb postures in larger animals should preferentially reduce anteroposterior (A‐P) relative to mediolateral (M‐L) bending of the limb bones and therefore decrease A‐P/M‐L rigidity. We test this hypothesis by examining growth‐related changes in limb bone structure in two primate taxa that differ in ontogenetic patterns of joint posture. Materials and Methods Knee and elbow angles of adult and immature vervets (Chlorocebus aethiops, n = 16) were compared to published data for baboons (Papio hamadryas ursinus, n = 33, Patel et al., ). Ontogenetic changes in ratios of A‐P/M‐L bending rigidity in the femur and humerus were compared in skeletal samples (C. aethiops, n = 28; P. cynocephalus, n = 39). Size changes were assessed with linear regression, and age group differences tested with ANOVA. Results Only the knee of baboons shows significant postural change, becoming more extended with age and mass. A‐P/M‐L bending rigidity of the femur decreases during ontogeny in immature and adult female baboons only. Trends in the humerus are less marked. Adult male baboons have higher A‐P/M‐L bending rigidity of the femur than females. Conclusions The hypothesized relationship between more extended joints and reduced A‐P/M‐L bending rigidity is supported by our results for immature and adult female baboon hind limbs, and the lack of significant age changes in either parameter in forelimbs and vervets. Adult males of both species depart from general ontogenetic trends, possibly due to socially mediated behavioral differences between sexes. Am J Phys Anthropol 161:72–83, 2016. © 2016 Wiley Periodicals, Inc.

  June 02, 2016   doi: 10.1002/ajpa.23009   open full text
• Canine and incisor microwear in pitheciids and Ateles reflects documented patterns of tooth use.
  Lucas K. Delezene, Mark F. Teaford, Peter S. Ungar.
  American Journal of Physical Anthropology. May 25, 2016
  Objectives Platyrrhine species differ in the extent to and the manner in which they use their incisors and canines during food ingestion. For example, Ateles uses its anterior teeth to process mechanically nondemanding soft fruits, while the sclerocarp‐harvesting pitheciids rely extensively on these teeth to acquire and process more demanding foods. Pitheciids themselves vary in anterior tooth use, with the pitheciines (Cacajao, Chiropotes, and Pithecia) noted to use their robust canines in a variety of ways to predate seeds, while Callicebus, which rarely predates seeds, uses its incisors and exceptionally short canines to scrape tough mesocarp from fruits. To investigate the relationship between tooth use and dental wear, microwear textures were investigated for the anterior teeth of these five genera of platyrrhine primates. Methods Using a white light confocal microscope, 12 microwear texture attributes that reflect feature size, anisotropy, density, and complexity were recorded from high‐resolution epoxy casts of the incisors and canines of adult wild‐collected Brazilian specimens of Ateles, Callicebus, Cacajao, Chiropotes, and Pithecia. Results Pitheciine canines tend to have deep microwear features and complex, anisotropic microwear textures, while Ateles anterior teeth tend to have very small features, low feature density, and less complex and anisotropic surfaces. Callicebus incisor and canine microwear is generally intermediate in size and complexity between those extremes. Conclusions These findings align with expectations from reported field observations of tooth use and illustrate the potential for using microwear texture analysis to infer patterns of anterior tooth use in extinct primates. Am J Phys Anthropol 161:6–25, 2016. © 2016 Wiley Periodicals, Inc.

  May 25, 2016   doi: 10.1002/ajpa.23002   open full text
• DNA methylation at stress‐related genes is associated with exposure to early life institutionalization.
  Amy L. Non, Brittany M. Hollister, Kathryn L. Humphreys, Ainash Childebayeva, Kyle Esteves, Charles H. Zeanah, Nathan A. Fox, Charles A. Nelson, Stacy S. Drury.
  American Journal of Physical Anthropology. May 24, 2016
  Objectives Differences in DNA methylation have been associated with early life adversity, suggesting that alterations in methylation function as one pathway through which adverse early environments are biologically embedded. This study examined associations between exposure to institutional care, quantified as the proportion of time in institutional care at specified follow‐up assessment ages, and DNA methylation status in two stress‐related genes: FKBP5 and SLC6A4. Materials and Methods We analyzed data from the Bucharest Early Intervention Project, which is a prospective study in which children reared in institutional settings were randomly assigned (mean age 22 months) to either newly created foster care or care as usual (to remain in their current placement) and prospectively followed. A group of children from the same geographic area, with no history of institutionalized caregiving, were also recruited. DNA methylation status was determined in DNA extracted from buccal epithelial cells of children at age 12. Results An inverse association was identified such that more time spent in institutional care was associated with lower DNA methylation at specific CpG sites within both genes. Discussion These results suggest a lasting impact of early severe social deprivation on methylation patterns in these genes, and contribute to a growing literature linking early adversity and epigenetic variation in children. Am J Phys Anthropol 161:84–93, 2016.. © 2016 Wiley Periodicals, Inc.

  May 24, 2016   doi: 10.1002/ajpa.23010   open full text
• Genetic variation in Tunisia in the context of human diversity worldwide.
  Lotfi Cherni, Andrew J. Pakstis, Sami Boussetta, Sarra Elkamel, Sabeh Frigi, Houssein Khodjet‐El‐Khil, Alison Barton, Eva Haigh, William C. Speed, Amel Ben Ammar Elgaaied, Judith R. Kidd, Kenneth K. Kidd.
  American Journal of Physical Anthropology. May 18, 2016
  Objectives North Africa has a complex demographic history of migrations from within Africa, Europe, and the Middle East. However, population genetic studies, especially for autosomal genetic markers, are few relative to other world regions. We examined autosomal markers for eight Tunisian and Libyan populations in order to place them in a global context. Materials and Methods Data were collected by TaqMan on 399 autosomal single nucleotide polymorphisms on 331 individuals from Tunisia and Libya. These data were combined with data on the same SNPs previously typed on 2585 individuals from 57 populations from around the world. Where meaningful, close by SNPs were combined into multiallelic haplotypes. Data were evaluated by clustering, principal components, and population tree analyses. For a subset of 102 SNPs, data from the literature on seven additional North African populations were included in analyses. Results Average heterozygosity of the North African populations is high relative to our global samples, consistent with a complex demographic history. The Tunisian and Libyan samples form a discrete cluster in the global and regional views and can be separated from sub‐Sahara, Middle East, and Europe. Within Tunisia the Nebeur and Smar are outlier groups. Across North Africa, pervasive East‐West geographical patterns were not found. Discussion Known historical migrations and invasions did not displace or homogenize the genetic variation in the region but rather enriched it. Even a small region like Tunisia contains considerable genetic diversity. Future studies across North Africa have the potential to increase our understanding of the historical demographic factors influencing the region. Am J Phys Anthropol 161:62–71, 2016. © 2016 The Authors American Journal of Physical Anthropology Published by Wiley Periodicals, Inc.

  May 18, 2016   doi: 10.1002/ajpa.23008   open full text
• Risk Minimization and a Late Holocene Increase in Mobility at Roonka Flat, South Australia: An Analysis of Lower Limb Bone Diaphyseal Shape.
  Ethan C. Hill, Arthur C. Durband, Keryn Walshe.
  American Journal of Physical Anthropology. May 18, 2016
  Objectives The strengthening of the El Niño Southern Oscillation (ENSO) in the mid‐Holocene caused significant changes in climate, vegetation, and faunal assemblages in South Australia. The appearance of a light, flexible backed‐artifact toolkit ∼4 kya has been interpreted as evidence for changes in foraging behavior in response to this event. Optimal foraging theory supports a risk minimization strategy for South Australian hunter‐gatherers in which increased mobility was used to cope with effects of a dryer, unstable environment in the late Holocene. Whether this event caused changes in foraging mobility will be tested by examining lower limb external diaphyseal shape between pre‐ENSO and post‐ENSO skeletons from Roonka Flat, South Australia. Materials and Methods Anteroposterior and mediolateral diameters were used to construct diaphyseal shape indices for Roonka Flat femora and tibiae. If populations living in South Australia became more mobile over time, then post‐ENSO skeletons should exhibit higher shape indices. Results The pooled‐sex post‐ENSO sample has significantly higher femoral shape indices than the pre‐ENSO sample. Males do not show significant diaphyseal shape differences over time, but females significantly increase. Discussion These data are consistent with the risk minimization model, indicating that South Australians became more mobile post‐ENSO to better exploit a less productive environment by expanding their foraging radii. The temporal shift toward more elliptical diaphyses is more notable in females than males, which is consistent with Aboriginal ethnographies that show both sexes being intensely involved in hunting and capturing game animals. Am J Phys Anthropol 161:94–103, 2016. © 2016 Wiley Periodicals, Inc.

  May 18, 2016   doi: 10.1002/ajpa.23011   open full text
• Morphometric patterns among the 3D surface areas of human hand entheses.
  Fotios Alexandros Karakostis, Carlos Lorenzo.
  American Journal of Physical Anthropology. May 11, 2016
  Objectives This study aimed to put forth a new and precise methodology for calculating the 3D areas of hand entheses. Furthermore, it investigated some of the factors affecting hand entheses development through an assessment of their correlations and morphometric patterns. Materials and methods Fifty individuals from late‐medieval San Pablo were studied. The sample consisted of high‐definition 3D models of 17 entheses from the first, second, and fifth hand rays. A new methodology was introduced for quantifying their areas. Precision was verified using intraobserved and interobserver tests. Both raw and relative entheseal size (ratio of entheseal size to total bone surface size) were calculated. Bivariate analyses assessed the effect of age‐group on entheses as well as the correlations across entheses of muscles that act synergistically, bone length, and articular surface size. The morphometric patterns among hand entheses were explored using a multivariate analysis. Results The methodology presented no significant error. Age‐group variation does not seem to affect hand entheses. In relative size, only particular pairs presented significant association and the entheses involved were not correlated with bone length or articular surface size. The multivariate analysis demonstrated high sexual dimorphism in overall entheseal size as well as two morphometric trends among hand entheses. Discussion The proposed methodology can set the basis for further morphological 3D analysis of entheses. If biomechanical stress affects hand entheses, its impact would possibly be greater on their relative size. The morphometric patterns among entheses seem to reflect the performance of prehensile grips. Am J Phys Anthropol 160:694–707, 2016. © 2016 Wiley Periodicals, Inc.

  May 11, 2016   doi: 10.1002/ajpa.22999   open full text
• Physical burden and lower limb bone structure at the origin of agriculture in the levant.
  Hila May, Christopher Ruff.
  American Journal of Physical Anthropology. May 11, 2016
  Objectives To examine the femoral midshaft morphological characteristics in hunter‐gathering Natufian and farming Pre‐pottery Neolithic (PPN) populations in the southern Levant and relate these to changes in mobility, physical stress, and diet. Materials and Methods 32 Natufian, 41 PPNB, and 26 PPNC femora, dating from 14,900 to 8,250 cal BP, were studied. Femoral diaphyseal cross‐sectional images were obtained from CT scans. Dedicated software was used to measure cross‐sectional breadths, areas, cortical bone thickness, rigidity, and strength. Results Two general temporal trends in femoral bone architecture were observed: (1) a continuous decline in the relative amount of bone tissue (cortical area/total area) due to expansion of the medullary cavity and (2) an increase in circularity (decrease in anteroposterior/mediolateral ratios) together with an overall decline in bone rigidity and strength, mainly apparent in the later PPNC. The first trend suggests a gradual decline in nutritional quality and health continuing from the Natufian through the late Neolithic. The second trend is interpreted as a result of increased sedentism with the full establishment of agriculture. Discussion The transition to food production in the southern Levant was accompanied by reduced physical stress and mobility, with the most marked effects occurring toward the end of the PPN with increasing sedentism. Deterioration of nutrition and health also occurred, but more continuously from the beginning of the PPN. Thus, environmental changes associated with the agricultural transition in this region of the world were gradual and prolonged, with direct dietary effects more apparent earlier than reductions in mobility. Am J Phys Anthropol 161:26–36, 2016. © 2016 Wiley Periodicals, Inc.

  May 11, 2016   doi: 10.1002/ajpa.23003   open full text
• Are simakobu (Simias concolor) loud calls energetically costly signals?
  Wendy M. Erb, Thomas Ziegler, Nurul S. Lestari, Kurt Hammerschmidt.
  American Journal of Physical Anthropology. May 06, 2016
  Objectives Male vocal displays play an important role in sexual selection in many species. If there are costs or constraints, calls may convey honest information about the caller. We studied the loud calls of male simakobu (Simias concolor), a sexually dimorphic primate that resides in one‐male groups, on Siberut Island, Indonesia. Materials and Methods We combined behavioral and ecological data with acoustic analysis to determine the influence of energy costs and status on calling effort. Based on all‐day follows (n = 107) and loud‐call recordings (n = 186), we determined how calling rates and durations varied in relation to short‐term (time of day, temperature, travel distance) and long‐term (fruit availability, physical condition) measures of energy availability and expenditure. Results We found that males avoided calling at the hottest times of the day, and produced shorter calls at higher temperatures, supporting the hypothesis that calls are influenced by thermoregulation costs. A peak of longer duration calls just before sunrise, however, could not be explained by energy constraints, but we hypothesize that this pattern is related to the fact that dawn calls occur in choruses, motivating males to call longer than their neighbors. Contrary to predictions, calling rates increased with decreasing fruit availability and did not appear to be energetically costly. Discussion We hypothesize that calling rates instead reflect strategies involving feeding and/or mate competition, signaling the motivation, rather than fighting ability, of the caller. Overall, results only weakly support the hypothesis that the timing and duration—but not rate—of simakobu loud calls are influenced by energy costs. Am J Phys Anthropol 161:44–52, 2016. © 2016 Wiley Periodicals, Inc.

  May 06, 2016   doi: 10.1002/ajpa.23005   open full text
• Morphological features of the fibula in Jomon hunter‐gatherers from the shell mounds of the Pacific coastal area.
  Yasuo Hagihara, Takashi Nara.
  American Journal of Physical Anthropology. May 03, 2016
  Objective The Jomon, one of the ancestral populations of modern Japanese, were hunter‐gatherers inhabiting the Japanese archipelago from 11,000 to 300 BC. We evaluated changes in the diaphyseal morphology of the fibula from the middle to the final phase of the Jomon period, compared to the morphology of other historical and modern populations from the Japanese archipelago, to elucidate temporal changes in habitual activities and possible division of labor among males and females. Material and Method Jomon specimens of 107 males and 97 females were obtained from the shell mounds of the Pacific coastal area of East Japan, distinguishing between middle (3,000–2,000 BC) and late‐final (2,000–300 BC) phases of the Jomon period. Mid‐shaft morphology of the fibula and tibia were compared to morphological measurements of specimens from Yayoi (37 males, 28 females), medieval (56 males, 56 females), early modern (51 males, 50 females), and modern (125 males, 68 females) periods. Result Largest values of fibular areas and relative fibular‐to‐tibial areas were identified in males from the late‐final Jomon phase, compared to the middle Jomon phase and after the Yayoi period. These period‐specific differences in fibular area were smaller in females, with the largest between‐sex difference identified in the late‐final Jomon phase. Discussion Results confirm a change in the habitual activity pattern of males in the late‐final phase. Males of the late‐final Jomon phase likely did more long‐distance traveling to the inland/mountainous region, as part of an ecological change that occurred during the middle to the late‐final Jomon phase. Am J Phys Anthropol 160:708–718, 2016. © 2016 Wiley Periodicals, Inc.

  May 03, 2016   doi: 10.1002/ajpa.23000   open full text
• Within arm's reach: Measuring forearm length to assess growth patterns in captive bonobos and chimpanzees.
  Verena Behringer, Jeroen M. G. Stevens, Tracy L. Kivell, Johanna Neufuss, Christophe Boesch, Gottfried Hohmann.
  American Journal of Physical Anthropology. May 03, 2016
  Objectives Bonobos and chimpanzees are known to differ in various morphological traits, a dichotomy that is sometimes used as an analogy for evolutionary splits during human evolution. The aim of our study was to measure the forearm length of immature and adult bonobos and adult chimpanzees to assess the extent of age–related changes of forearm length in bonobos and sex–dimorphism in bonobos and chimpanzees. Materials and methods As a proxy of somatic growth we measured forearm length of captive bonobos and chimpanzees ranging in age from 1 to 55 years. Measures were taken from subjects inserting their arms into a transparent Plexiglas® tube, a novel technique facilitating repeated measures of nonanesthetized apes in captivity. Results Measures from adult females (>12 years) showed that bonobos exceed chimpanzees in terms of forearm length and that sexual dimorphism in forearm length is pronounced in chimpanzees, but not in bonobos. Forearm length increased significantly with chronological age in bonobos. Validation tests revealed that the device generates useful data on morphometric dimensions. Discussion In most primates, sexual dimorphism in body size is male‐biased and the differences in forearm length in chimpanzees follow this trend. Given that males of the two species did not differ in forearm length, the absence/presence of sexual dimorphism of this trait must be due to differences in somatic growth in females. Our novel method offers an alternative to obtain morphometric measures and facilitates longitudinal studies on somatic growth. Am J Phys Anthropol 161:37–43, 2016. © 2016 Wiley Periodicals, Inc.

  May 03, 2016   doi: 10.1002/ajpa.23004   open full text
• Wild capuchin monkeys spontaneously adjust actions when using hammer stones of different mass to crack nuts of different resistance.
  Qing Liu, Dorothy M. Fragaszy, Elisabetta Visalberghi.
  American Journal of Physical Anthropology. May 02, 2016
  Objectives Expert tool users are known to adjust their actions skillfully depending on aspects of tool type and task. We examined if bearded capuchin monkeys cracking nuts with stones of different mass adjusted the downward velocity and the height of the stone when striking palm nuts. Materials and Methods During a field experiment carried out in FBV (Piauí, Brazil), eight adult wild capuchin monkeys (five males) cracked Orbygnia nuts of varied resistance with hammer stones differing in mass. From recorded videos, we identified the highest strike per nut‐cracking episode, and for this strike, we calculated the height to which the monkey lifted the stone, the maximum velocity of the stone during the downward phase, the work done on the stone, and the kinetic energy of the strike. Results We found that individual capuchins achieved average maximum kinetic energy of 8.7–16.1 J when using stones between 0.9 and 1.9 kg, and maximum kinetic energy correlated positively with mass of the stone. Monkeys lifted all the stones to an individually consistent maximum height but added more work to the stone when using lighter stones. One male and one female monkey lifted stones higher when they cracked more resistant nuts. The high resistance of the Orbygnia nut elicits production of maximum kinetic energy, which the monkeys modulate to some degree by adding work to lighter stones. Discussion Capuchin monkeys, like chimpanzees, modulate their actions in nut‐cracking, indicating skilled action, although neither species regulates kinetic energy as precisely as skilled human stone knappers. Kinematic analyses promise to yield new insights into the ways and extent to which nonhuman tool users develop expertise. Am J Phys Anthropol 161:53–61, 2016. © 2016 Wiley Periodicals, Inc.

  May 02, 2016   doi: 10.1002/ajpa.23006   open full text
• Variation of skeletal degenerative joint disease features in an identified Italian modern skeletal collection.
  Stefania Zampetti, Valentina Mariotti, Nico Radi, Maria Giovanna Belcastro.
  American Journal of Physical Anthropology. April 28, 2016
  Objectives The objective of this study was to investigate the relationship of degenerative joint disease (DJD) features (marginal lipping, porosity, surface osteophytes, eburnation, and loss of joint morphology) with sex, age, and occupation. Materials and Methods We devised a recording method for scoring the single features in the shoulder, elbow, wrist, hip, knee, and ankle of an Italian skeletal sample of 332 individuals (males = 161, females = 171) of known sex, age, and occupation from the Frassetto collection (Sassari, Sardinia, 19th–20th century). Results Our data revealed that: (1) the frequency of all features increases with age; (2) porosity is the first feature to appear, being in general the most frequent feature in young adults; (3) sex differences are especially found in the upper limbs of mature and elderly adults; (4) marginal lipping and surface osteophytes show a lesser age correlation and, in general, higher frequencies in the left lower limb; (5) no differences were found among different occupations. Discussion We explain these results in light of different metabolic and adaptive processes in relation to age and sex. Static (weight‐bearing) rather than dynamic mechanical stress could play a pivotal role in the distribution of the features observed in the lower limbs. The considerable increase in marginal lipping and surface osteophytes in elderly adults may be an adaptation for sustaining mechanical loading, balancing the loss of bone tissue which is characteristic of ageing processes (osteopenia, osteoporosis). Am J Phys Anthropol, 2016. © 2016 Wiley Periodicals, Inc. Am J Phys Anthropol 160:683–693, 2016. © 2016 Wiley Periodicals, Inc.

  April 28, 2016   doi: 10.1002/ajpa.22998   open full text
• New cases of trepanations from the 5th to 3rd millennia BC in Southern Russia in the context of previous research: Possible evidence for a ritually motivated tradition of cranial surgery?
  Julia Gresky, Elena Batieva, Alexandra Kitova, Alexey Kalmykov, Andrey Belinskiy, Sabine Reinhold, Nataliya Berezina.
  American Journal of Physical Anthropology. April 21, 2016
  Objectives It is a big challenge to diagnose the motives behind trepanations in prehistoric crania. Surgical‐therapeutic attempts may be apparent by the presence of fractures, however, ritual or nonmedical motives are rarely supported by visible evidence in the bones. This article presents data on the trepanations of several individuals from South Russia dating to the Eneolitic and Bronze Age that may indicate a ritual procedure. In these crania an operation was performed in the identical location, the midline, furthermore in one of the most dangerous places, on the obelion. No evidence for traumatic or other pathological reasons for performing the operations was observable. Material and Methods Investigations of two nearby areas of South Russia revealed 13 individuals showing complete perforations in the midline of the cranium. Another one, displaying a depression in the same place, primarily diagnosed as an incomplete trepanation, is discussed considering all differential diagnoses. The trepanations were investigated macroscopically, by plain radiography and computed tomography. The lesions were described in detail, including data on technique, position, size, shape, state of healing, and complications. Results Males and females received the operation between the age of 10 years and mature/senile age. Only grooving and scraping techniques were used and their application differed between sexes. The majority of the patients survived the intervention for a long time. Discussion The region of Southern Russia seems to be a center for special trepanations performed by skilled surgeons, the specific position of the perforations implying more a ritual than therapeutic reason for trepanning. Am J Phys Anthropol 160:665–682, 2016. © 2016 Wiley Periodicals, Inc.

  April 21, 2016   doi: 10.1002/ajpa.22996   open full text
• Subadult dietary variation at Trino Vercellese, Italy, and its relationship to adult diet and mortality.
  Laurie J. Reitsema, Giuseppe Vercellotti, Rosa Boano.
  American Journal of Physical Anthropology. April 21, 2016
  Objectives Early‐life nutrition is a predisposing factor for later‐life outcomes. This study tests the hypothesis that subadults from medieval Trino Vercellese, Italy, who lived to adulthood consumed isotopically different diets compared with subadults who died before reaching adulthood. We have previously used a life history approach, comparing dentine and bone of the same adult individuals (“subadults who lived”), to elucidate dietary variation across the life span. Here, we examine diets of “subadults who died” from the same population, estimated from subadult rib collagen, to explore whether dietary behaviors of subadults who lived differed from those of subadults who died. Methods Forty‐one subadults aged six months to 14.5 years were studied through stable carbon and nitrogen isotope analysis of collagen. Results Individuals were weaned by age 4 years, with considerable variation in weaning ages overall. Post‐weaning, diets of subadults who died comprised significantly less animal protein than diets of subadults who lived. Isotopic values of the two oldest individuals, 13.5 and 14.5 years, show the same status‐based variation in diet as do adults from the population. Conclusions Our results suggest that incorporating animal protein in diet during growth and development supported medieval subadults' ability to survive to adulthood. Isotopic similarities between adults and older subadults suggest “adult” dietary behaviors were adopted in adolescence. Stable isotope evidence from subadults bridges a disparity between ontogenetic age categories and socioculturally meaningful age categories in the past, and sheds light on the underpinnings of health, mortality, growth, and disease in the bioarchaeological record. Am J Phys Anthropol 160:653–664, 2016. © 2016 Wiley Periodicals, Inc.

  April 21, 2016   doi: 10.1002/ajpa.22995   open full text
• A validated method for modeling anthropoid hip abduction in silico.
  Ashley S. Hammond, J. Michael Plavcan, Carol V. Ward.
  American Journal of Physical Anthropology. April 18, 2016
  Objectives The ability to reconstruct hip joint mobility from femora and pelves could provide insight into the locomotion and paleobiology of fossil primates. This study presents a method for modeling hip abduction in anthropoids validated with in vivo data. Methods Hip abduction simulations were performed on a large sample of anthropoids. The modeling approach integrates three‐dimensional (3D) polygonal models created from laser surface scans of bones, 3D landmark data, and shape analysis software to digitally articulate and manipulate the hip joint. Range of femoral abduction (degrees) and the abducted knee position (distance spanned at the knee during abduction) were compared with published live animal data. Results The models accurately estimate knee position and (to a lesser extent) angular abduction across broad locomotor groups. They tend to underestimate abduction for acrobatic or suspensory taxa, but overestimate it in more stereotyped taxa. Correspondence between in vivo and in silico data varies at the specific and generic level. Conclusions Our models broadly correspond to in vivo data on hip abduction, although the relationship between the models and live animal data is less straightforward than hypothesized. The models can predict acrobatic or stereotyped locomotor adaptation for taxa with values near the extremes of the range of abduction ability. Our findings underscore the difficulties associated with modeling complex systems and the importance of validating in silico models. They suggest that models of joint mobility can offer additional insight into the functional abilities of extinct primates when done in consideration of how joints move and function in vivo. Am J Phys Anthropol 160:529–548, 2016. © 2016 Wiley Periodicals, Inc.

  April 18, 2016   doi: 10.1002/ajpa.22990   open full text
• Mobility during the neolithic and bronze age in northern ireland explored using strontium isotope analysis of cremated human bone.
  Christophe Snoeck, John Pouncett, Greer Ramsey, Ian G. Meighan, Nadine Mattielli, Steven Goderis, Julia A. Lee‐Thorp, Rick J. Schulting.
  American Journal of Physical Anthropology. April 09, 2016
  Objectives As many individuals were cremated in Neolithic and Bronze Age Ireland, they have not featured in investigations of individual mobility using strontium isotope analysis. Here, we build on recent experiments demonstrating excellent preservation of biogenic 87Sr/86Sr in calcined bone to explore mobility in prehistoric Northern Ireland. Materials and Methods A novel method of strontium isotope analysis is applied to calcined bone alongside measurements on tooth enamel to human remains from five Neolithic and Bronze Age sites in Northern Ireland. We systematically sampled modern vegetation around each site to characterize biologically available strontium, and from this calculated expected values for humans consuming foods taken from within 1, 5, 10 and 20 Km catchments. This provides a more nuanced way of assessing human use of the landscape and mobility than the ‘local’ vs. ‘non‐local’ dichotomy that is often employed. Results The results of this study 1) provide further support for the reliability of strontium isotope analysis on calcined bone, and 2) demonstrate that it is possible to identify isotopic differences between individuals buried at the same site, with some consuming food grown locally (within 1‐5 Km) while others clearly consumed food from up to 50 Km away from their burial place. Discussion Hints of patterning emerge in spite of small sample numbers. At Ballynahatty, for instance, those represented by unburnt remains appear to have consumed food growing locally, while those represented by cremated remains did not. Furthermore, it appears that some individuals from Ballynahatty, Annaghmare and Clontygora either moved in the last few years of their life or their cremated remains were brought to the site. These results offer new insights into the choice behind coterminous cremation and inhumation rites in the Neolithic. Am J Phys Anthropol 160:397–413, 2016. © 2016 Wiley Periodicals, Inc.

  April 09, 2016   doi: 10.1002/ajpa.22977   open full text
• Incisor ablation among the late upper paleolithic people of Tam Hang (Northern Laos): Social identity, mortuary practice, and oral health.
  John C. Willman, Laura Shackelford, Fabrice Demeter.
  American Journal of Physical Anthropology. April 08, 2016
  Objectives A detailed assessment of intentional incisor ablation among the Late Upper Paleolithic people of Tam Hang (northern Laos) was undertaken to understand how this cultural practice, in addition to age and sex, influenced an individual's inclusion in the mortuary context. The covariation of ablation status with occlusal variation and anterior dental pathology was addressed to study the implications of this cultural practice on oral health. Materials and Methods Sex, age, caries, antemortem tooth loss, and occlusal variation were assessed through standard osteological methods for 12 individuals. An observational protocol to identify intentional ablation was developed specifically for this sample. Results Four ablation states were identified that range from no ablation to the removal of two, three, or four lateral (I2) incisors. The timing of ablation was attributed to ritual extractions during early adolescence. Adult age‐at‐death was the strongest indicator of inclusion in the main burial context and a child burial was isolated from those of adults. Ablation status does not strongly influence inclusion in the mortuary context. Individuals lacking ablation tended to have a higher incidence of anterior caries, pathological tooth loss, incisor crowding, and canine rotation. Conclusions This study identifies the oldest case of intentional incisor ablation in Late Pleistocene Mainland Southeast Asia. We conclude that ablation does not always “compromise” the dentition; instead, it may have unintentional oral health benefits in some contexts. Am J Phys Anthropol 160:519–528, 2016. © 2016 Wiley Periodicals, Inc.

  April 08, 2016   doi: 10.1002/ajpa.22988   open full text
• Patterns of quadrupedal locomotion in a vertical clinging and leaping primate (Propithecus coquereli) with implications for understanding the functional demands of primate quadrupedal locomotion.
  Michael C. Granatosky, Cameron H. Tripp, Anne‐Claire Fabre, Daniel Schmitt.
  American Journal of Physical Anthropology. April 07, 2016
  Objectives Many primates exhibit a suite of characteristics that distinguish their quadrupedal gaits from non‐primate mammals including the use of a diagonal sequence gait, a relatively protracted humerus at touchdown, and relatively high peak vertical forces on the hindlimbs compared to the forelimbs. These characteristics are thought to have evolved together in early, small‐bodied primates possibly in response to the mechanical demands of navigating and foraging in a complex arboreal environment. It remains unclear, however, whether primates that employ quadrupedalism only rarely demonstrate the common primate pattern of quadrupedalism or instead use the common non‐primate pattern or an entirely different mechanical pattern from either group. Materials and Methods This study compared the kinematics and kinetics of two habitually quadrupedal primates (Lemur catta and Varecia variegata) to those of a dedicated vertical clinger and leaper (Propithecus coquereli) during bouts of quadrupedal walking. Results All three species employed diagonal sequence gaits almost exclusively, displayed similar degrees of humeral protraction, and exhibited lower vertical peak forces in the forelimbs compared to the hindlimb. Discussion From the data in this study, it is possible to reject the idea that P. coquereli uses a non‐primate pattern of quadrupedal walking mechanics. Nor do they use an entirely different mechanical pattern from either most primates or most non‐primates during quadrupedal locomotion. These findings provide support for the idea that this suite of characteristics is adaptive for the challenges of arboreal locomotion in primates and that these features of primate locomotion may be basal to the order or evolved independently in multiple lineages including indriids. Am J Phys Anthropol 160:644–652, 2016. © 2016 Wiley Periodicals, Inc.

  April 07, 2016   doi: 10.1002/ajpa.22991   open full text
• Stable isotope study on ancient populations of central sudan: Insights on their diet and environment.
  Paola Iacumin, Antonietta Di Matteo, Donatella Usai, Sandro Salvatori, Giampiero Venturelli.
  American Journal of Physical Anthropology. April 07, 2016
  Objectives A contribution to the knowledge of the economy and the environmental surroundings of the populations living along the Nile valley in three different periods. Materials and methods This study reports stable isotope analyses on apatite bone samples of 139 humans, 48 mammals, and 43 fish from the Al Khiday archaeological sites in Sudan. The bones belong to four archaeological periods: pre‐Mesolithic, Mesolithic, Neolithic, and Meroitic. Data were processed statistically. Results A significant difference exists between the pre‐Mesolithic and Mesolithic mean δ18Ow value and the mean of the modern Nile. The mean δ18Ow values for the Neolithic humans and bovids are very similar (+1.5‰ ±4‰, and −2‰, respectively) and more positive than the mean values of Mesolithic mammals and Pre‐Mesolithic humans. The water ingested by Meroitic humans (+7‰ ± 2.5‰) is enriched in 18O in respect to the water ingested by the Neolithic population. There is a separation in the δ13Cdiet values between the pre‐Mesolithic humans (−14‰ ± 1‰) and Mesolithic mammals (−12‰ ± 2‰) group and the Neolithic humans (−18‰ ± 1‰), Meroitic humans (−19‰ ±1‰), Neolithic mammals (−21‰), and the modern (mean δ13Cdiet = −19‰ ±2‰) mammal group. Discussion The climate became warmer and more arid from the pre‐Mesolithic/Mesolithic to the Meroitic period. The environmental conditions influenced the strategies of subsistence and, in particular, the changes occurring from the pre‐Mesolithic to the Neolithic can be considered contemporaneous to the transition from hunting‐gathering‐fishing to cultivation‐herding. Am J Phys Anthropol 160:498–518, 2016. © 2016 Wiley Periodicals, Inc.

  April 07, 2016   doi: 10.1002/ajpa.22987   open full text
• One for all and all for one: Linear regression from the mass of individual bones to assess human skeletal mass completeness.
  David Gonçalves, João d'Oliveira Coelho, Maria A. Acosta, Catarina Coelho, Francisco Curate, Maria Teresa Ferreira, Márcia Gouveia, Calil Makhoul, Débora Pinto, Inês Oliveira‐Santos, Ana R. Vassalo, David Navega, Eugénia Cunha.
  American Journal of Physical Anthropology. April 05, 2016
  Objectives Complete and accurate human skeletal inventory is seldom possible in archaeological and forensic cases involving severe fragmentation. In such cases, skeletal mass comparisons with published references may be used as an alternative to assess skeletal completeness but they are too general for a case‐by‐case routine analysis. The objective is to solve this issue by creating linear regression equations to estimate the total mass of a skeleton based on the mass of individual bones. Materials and Methods Total adult skeletal mass and individual mass of the clavicle, humerus, femur, patella, carpal, metacarpal, tarsal, and metatarsal bones were recorded in a sample of 60 skeletons from the 21st century identified skeletal collection (University of Coimbra). The sample included 32 females and 28 males with ages ranging from 31 to 96 years (mean = 76.4; sd = 14.8). Skeletal mass linear regression equations were calculated based on this sample. Results The mass of individual bones was successfully used to predict the approximate total mass of the adult skeleton. The femur, humerus, and second metacarpal were the best predictors of total skeletal mass with root mean squared errors ranging from 292.9 to 346.1 g. Discussion Linear regression was relatively successful at estimating adult skeletal mass. The non‐normal distribution of the sample in terms of mass may have reduced the predictive power of the equations. These results have clear impact for bioanthropology, especially forensic anthropology, since this method may provide better estimates of the completeness of the skeleton or the minimum number of individuals. Am J Phys Anthropol 160:427–432, 2016. © 2016 Wiley Periodicals, Inc.

  April 05, 2016   doi: 10.1002/ajpa.22979   open full text
• The endocast of the one‐million‐year‐old human cranium from Buia (UA 31), Danakil Eritrea.
  Emiliano Bruner, Luca Bondioli, Alfredo Coppa, David W. Frayer, Ralph L. Holloway, Yosief Libsekal, Tsegai Medin, Lorenzo Rook, Roberto Macchiarelli.
  American Journal of Physical Anthropology. April 04, 2016
  Objectives The Homo erectus‐like cranium from Buia (UA 31) was found in the Eritrean Danakil depression and dated to 1 million years. Its outer morphology displays archaic traits, as well as distinctive and derived characters. The present study provides the description and metric comparison of its endocranial anatomy. Materials and Methods UA 31 was originally filled by a diffuse concretion. Following its removal and cleaning, the endocast (995 cc) was reconstructed after physical molding and digital scan. Its morphology is here compared with specimens belonging to different human taxa, taking into account endocranial metrics, cortical traits, and craniovascular features. Results The endocast is long and narrow when compared to the H. erectus/ergaster hypodigm, although its proportions are compatible with the morphology displayed by all archaic and medium‐brained human species. The occipital areas display a pronounced bulging, the cerebellum is located in a posterior position, and the middle meningeal vessels are more developed in the posterior regions. These features are common among specimens attributed to H. erectus s.l., particularly the Middle Pleistocene endocasts from Zhoukoudian. The parietal lobes are markedly bossed. This lateral bulging is associated with the lower parietal circumvolutions, as in other archaic specimens. This pronounced parietal curvature is apparently due to a narrow cranial base, more than to wider parietal areas. Conclusions The endocast of UA 31 shows a general plesiomorphic phenotype, with some individual features (e.g., dolichocephaly and rounded lower parietal areas) which confirm a remarkable degree of morphological variability within the H. erectus/ergaster hypodigm. Am J Phys Anthropol 160:458–468, 2016. © 2016 Wiley Periodicals, Inc.

  April 04, 2016   doi: 10.1002/ajpa.22983   open full text
• Cycle‐phase dependent associations between CRP, leptin, and reproductive hormones in an urban, Canadian sample.
  Kathryn B.H. Clancy, Angela R. Baerwald, Roger A. Pierson.
  American Journal of Physical Anthropology. March 24, 2016
  Objectives To assess the relationships among reproductive hormones, follicular development, inflammation, and adiposity in a sample of urban, Canadian women. Materials and Methods Participants (n = 41) had blood collected every 3 days through one interovulatory interval (IOI) to measure estradiol, progesterone, LH, FSH, leptin, and C‐reactive protein (CRP). Participants underwent daily transvaginal ultrasound examinations during the IOI to quantify all follicles > 2 mm. CRP and leptin tertiles were used to compare conditions of high and low inflammatory processes and adiposity, respectively. Results Luteal phase estradiol, luteal phase LH, and follicular phase progesterone were lower among individuals in the highest CRP tertile (adjusted r2 = 0.63, 0.70, 0.76, respectively). Luteal and follicular phase follicle diameter was greatest in the high CRP tertile (adjusted r2 = 0.68, 0.71). Follicular phase progesterone was lowest among individuals in the highest leptin tertile, and follicular phase FSH was lowest among individuals in the lowest leptin tertile (adjusted r2 = 0.54, 0.45). Luteal phase follicle diameter was highest among those in the moderate leptin tertile (adjusted r2 = 0.49). Discussion This study is a first comprehensive assessment of the relationship between multiple ovarian function components and inflammatory biomarkers. The results are interpreted to mean that inflammatory and energetic stressors produce differential effects depending on population, adiposity, and cycle phase. Am J Phys Anthropol 160:389–396, 2016. © 2016 Wiley Periodicals, Inc.

  March 24, 2016   doi: 10.1002/ajpa.22976   open full text
• Morphological Covariation between the Maxillary Sinus and Midfacial Skeleton among Sub‐Saharan and Circumpolar Modern Humans.
  Lauren N. Butaric, Scott D. Maddux.
  American Journal of Physical Anthropology. March 24, 2016
  Objectives Maxillary sinus volume tracks ecogeographic differences in nasal form and may serve as a zone of accommodation for ontogenetic and evolutionary changes in nasal cavity breadth. However, little is known regarding how sinus volume is distributed within the midface. This study investigates morphological covariation between midfacial and sinus shape to better understand structural and functional relationships between the sinus, midface, and nasal cavity. Methods Cranial and sinus models were rendered from CT scans of modern human samples from two disparate climates: sub‐Saharan (South Africans [n = 15], West Africans [n = 17]), and circumpolar (Siberian Buriats [n = 18], Alaskan Inuit [n = 20]). Twenty‐five 3D coordinate landmarks were placed on the models and subjected to generalized Procrustes analysis. Two‐block partial least squares (2B‐PLS) analysis was employed to identify patterns of covariation. Results The 2B‐PLS analysis indicates PLS1 (58.6% total covariation) relates to height and breadth relationships between the midface, nasal cavity, and maxillary sinus. Significant regional differences in PLS1 scores are evident: circumpolar samples possess taller/narrower noses with taller/wider sinuses compared to sub‐Saharan samples. Importantly, PLS1 indicates that sinus breadth is not exclusively related to nasal cavity breadth; variation in lateral sinus expansion toward the zygoma represents an important contributing factor. PLS2 (16%) relates to supero‐inferior positioning of the sinus within the midface. Allometric trends, while statistically significant, explain only a small portion of these covariation patterns. Conclusions These results suggest that the maxillary sinus serves as a zone of accommodation at the confluence of multiple facial components, potentially minimizing effects of morphological alterations to certain components on adjacent structures. Am J Phys Anthropol 160:483–497, 2016. © 2016 Wiley Periodicals, Inc.

  March 24, 2016   doi: 10.1002/ajpa.22986   open full text
• Conarticular congruence of the hominoid subtalar joint complex with implications for joint function in Plio‐Pleistocene hominins.
  Thomas C. Prang.
  American Journal of Physical Anthropology. March 22, 2016
  Objective The purpose of this study is to test the hypothesis that conarticular surfaces areas and curvatures are correlates of mobility at the hominoid talocalcaneal and talonavicular joints. Materials and Methods Articular surface areas and curvatures of the talonavicular, anterior talocalcaneal, and posterior talocalcaneal joints were quantified using a total of 425 three‐dimensional surface models of extant hominoid and fossil hominin tali, calcanei, and naviculars. Quadric surface fitting was used to calculate curvatures, pairwise comparisons were used to evaluate statistical differences between taxa, and regression was used to test for the effects of allometry. Results Pairwise comparisons show that the distributions of values for joint curvature indices follow the predicted arboreal‐terrestrial morphocline in hominoid primates with no effect of body mass (PGLS p > 0.05). OH 8 (Homo habilis) and LB 1 (Homo floresiensis) can be accommodated within the range of human variation for the talonavicular joint, whereas MH2 (Australopithecus sediba) falls within the ranges of variation for Pan troglodytes and Gorilla gorilla in measures of posterior talocalcaneal joint congruity. Conclusions Joint curvature indices are better discriminators than joint surface area indices, which may reflect a greater contribution of rotation, rather than translation, to joint movement in plantigrade taxa due to discrepancies in conarticular congruence and the “convex‐concave” rule. The pattern of joint congruence in Au. sediba contributes to other data on the foot and ankle suggesting that the lateral side of the foot was more mobile than the medial side, which is consistent with suggestions of increased medial weight transfer associated with hyperpronation. Am J Phys Anthropol 160:446–457, 2016. © 2016 Wiley Periodicals, Inc.

  March 22, 2016   doi: 10.1002/ajpa.22982   open full text
• Carpal bones of Nacholapithecus kerioi, a Middle Miocene Hominoid From Northern Kenya.
  Naomichi Ogihara, Sergio Almécija, Masato Nakatsukasa, Yoshihiko Nakano, Yasuhiro Kikuchi, Yutaka Kunimatsu, Haruyuki Makishima, Daisuke Shimizu, Tomo Takano, Hiroshi Tsujikawa, Miyuki Kagaya, Hidemi Ishida.
  American Journal of Physical Anthropology. March 22, 2016
  Objectives The carpal bones of the middle Miocene hominoid Nacholapithecus kerioi are described based on new materials. Materials and Methods The materials comprise a trapezoid, three capitates, two hamates, a centrale, a lunate, a triquetrum, and a pisiform, collected during the 2001 and 2002 field seasons from Nachola, Kenya. We also describe a pisiform recently assigned to the type specimen of N. kerioi, KNM‐BG 35250. Results In the Nacholapithecus wrist, the ulnar styloid process articulates with both the triquetrum and pisiform, and the triquetrum facet on the hamate is relatively proximodistally oriented in dorsal view. The Nacholapithecus capitate possesses a moderate distopalmar hook‐like process and separated radial articular facets for the trapezoid and the second metacarpal due to the carpometacarpal ligament attachment that is absent in the Proconsul capitate. Discussion The carpal anatomy of Nacholapithecus is similar to that of the early Miocene hominoid Proconsul. However, Nacholapithecus wrist anatomy appears to exhibit slightly more emphasized stability. Am J Phys Anthropol 160:469–482, 2016. © 2016 Wiley Periodicals, Inc.

  March 22, 2016   doi: 10.1002/ajpa.22984   open full text
• Successful enrichment and recovery of whole mitochondrial genomes from ancient human dental calculus.
  Andrew T. Ozga, Maria A. Nieves‐Colón, Tanvi P. Honap, Krithivasan Sankaranarayanan, Courtney A. Hofman, George R. Milner, Cecil M. Lewis, Anne C. Stone, Christina Warinner.
  American Journal of Physical Anthropology. March 16, 2016
  Objectives Archaeological dental calculus is a rich source of host‐associated biomolecules. Importantly, however, dental calculus is more accurately described as a calcified microbial biofilm than a host tissue. As such, concerns regarding destructive analysis of human remains may not apply as strongly to dental calculus, opening the possibility of obtaining human health and ancestry information from dental calculus in cases where destructive analysis of conventional skeletal remains is not permitted. Here we investigate the preservation of human mitochondrial DNA (mtDNA) in archaeological dental calculus and its potential for full mitochondrial genome (mitogenome) reconstruction in maternal lineage ancestry analysis. Materials and Methods Extracted DNA from six individuals at the 700‐year‐old Norris Farms #36 cemetery in Illinois was enriched for mtDNA using in‐solution capture techniques, followed by Illumina high‐throughput sequencing. Results Full mitogenomes (7–34×) were successfully reconstructed from dental calculus for all six individuals, including three individuals who had previously tested negative for DNA preservation in bone using conventional PCR techniques. Mitochondrial haplogroup assignments were consistent with previously published findings, and additional comparative analysis of paired dental calculus and dentine from two individuals yielded equivalent haplotype results. All dental calculus samples exhibited damage patterns consistent with ancient DNA, and mitochondrial sequences were estimated to be 92–100% endogenous. DNA polymerase choice was found to impact error rates in downstream sequence analysis, but these effects can be mitigated by greater sequencing depth. Discussion Dental calculus is a viable alternative source of human DNA that can be used to reconstruct full mitogenomes from archaeological remains. Am J Phys Anthropol 160:220–228, 2016. © 2016 The Authors American Journal of Physical Anthropology Published by Wiley Periodicals, Inc.

  March 16, 2016   doi: 10.1002/ajpa.22960   open full text
• A bioarchaeological analysis of oral and physiological health on the south coast of New Guinea.
  Rebecca L. Kinaston, Georgia L. Roberts, Hallie R. Buckley, Marc Oxenham.
  American Journal of Physical Anthropology. March 15, 2016
  Objectives The south coast of New Guinea has a complex prehistory known for its exchange systems that linked distinct cultural groups living along the coast, inland, and on offshore islands. Here we compare the palaeohealth of two relatively contemporaneous skeletal samples from the south coast of New Guinea (850–200 BP) that were from two ecologically different sites (one inland and one offshore island) and likely represent distinct cultural groups. We aim to elucidate health patterns that may provide information about the specific lifeways and quality of life of each community. Materials and Methods Oral conditions (caries, calculus, alveolar lesions, and antemortem tooth loss [AMTL]) were analyzed macroscopically to assess possible intra‐ and inter‐population variation in oral and physiological health. The frequency of linear enamel hypoplasia (LEH) was also used as a nonspecific indicator of stress to assess childhood health at each site. Results The inhabitants from the small offshore island of Motupore, thought to be associated with Austronesian‐speaking Motu tribes, displayed different patterns of oral pathological conditions (more carious lesions on the tooth crown and calculus) and LEH (lower frequencies) compared with inland people residing at the site of Nebira. Discussion It is suggested that the causes for the variation in oral and physiological health were likely multifactorial and potentially associated with variables such as the ecological and geographical settings of the sites, cultural differences, infectious disease, differential fertility and, potentially, diet. This research provides previously unknown information about possible culturally‐moderated practices that affected health in the past. Am J Phys Anthropol 160:414–426, 2016. © 2016 Wiley Periodicals, Inc.

  March 15, 2016   doi: 10.1002/ajpa.22978   open full text
• Isotopic perspectives (δ13C, δ15N, δ34S) of diet, social complexity, and animal husbandry during the proto‐shang period (ca. 2000–1600 BC) of China.
  Ying Ma, Benjamin T. Fuller, Dong Wei, Lei Shi, Xiaozheng Zhang, Yaowu Hu, Michael P. Richards.
  American Journal of Physical Anthropology. March 12, 2016
  Objectives To examine dietary patterns and animal husbandry practices and assess the links between human diet and sex, age, burial direction/position, and social status (as inferred by type of grave goods) during the transformative Proto‐Shang (ca. 2000–1600 BC) period of China. Materials and Methods Stable isotope ratios of carbon (δ13C), nitrogen (δ15N), and sulfur (δ34S) were analyzed from human (n = 83) and animal (n = 36) bone collagen at the site of Nancheng in Hebei Province, China. Results The Proto‐Shang population consumed a predominately C4 diet (δ13C = −6.8 ± 0.4‰; δ15N = 9.4 ± 0.6‰), but a single individual (M70) had a mixed C3/C4 diet (δ13C = −14.9‰; δ15N = 10.1‰). The δ34S measurement of M70 (8.8‰) is similar to the local animals (8.2 ± 2.6‰) and the other members of the population (7.0 ± 0.8‰) suggesting this individual may not have been a migrant even though the burial direction (north‐south) and position (flexed) was different than the majority of the graves in the cemetery. Discussion From comparison with the faunal bone collagen stable isotope results, the Nancheng population ate millets with varying levels of animal protein consumption focused primarily on pigs and possibly cattle and dogs, but sheep/goats, and deer were not eaten in significant amounts. Analysis of the isotopic results in relation to other contemporary sites such as Liuzhuang and Xinzhai show strikingly similar patterns, suggesting that the sheep/goats were likely raised mainly for their secondary products (e.g., wool). No link between diet and sex was found at the population level, but when the data were sorted by age and sex, the older males (>40 years old) were found to have significantly lower δ13C values (−6.6 ± 0.3‰; n = 18) compared to the younger males (<40 years old) (−7.3 ± 0.5‰; n = 8). Further, no significant correlations between diet and burial direction/position or social status (based on the type of grave goods) were found at Nancheng, possibly indicating that the dietary social stratification of the later Shang and Zhou Dynasties had yet to be established in Chinese society at this time. Am J Phys Anthropol 160:433–445, 2016.. © 2016 Wiley Periodicals, Inc.

  March 12, 2016   doi: 10.1002/ajpa.22980   open full text
• The endocranial anatomy of maba 1.
  Xiu‐jie Wu, Emiliano Bruner.
  American Journal of Physical Anthropology. March 12, 2016
  Objectives Maba 1, a partial cranium from Guandong Province (China) tentatively dated between 300 and 130 ka, has been suggested to display a mosaic of archaic and derived features, including facial affinities with Neandertals. This study aims to evaluate whether Maba 1 shows a derived endocranial phenotype, or if it displays a plesiomorphic braincase morphology. Materials and methods We analyzed a set of metric variables on fossil and modern human endocasts using bivariate correlation, principal component analysis, and cluster analyses, to evaluate the morphological affinities of the Maba 1 endocast. Results The cranial capacity, estimated at around 1300 cc, and the endocranial proportions of Maba 1 are within the ranges of modern humans, Neandertals and Homo heidelbergensis. However, the frontal lobes are narrow and the parietal areas are short and flattened, as in H. heidelbergensis and H. erectus. Nonetheless, the position of the frontal lobes relative to the orbits, the morphology of the frontal sinus and the curve of the frontal squama are more derived, being similar to Neandertals and modern humans. Conclusions The endocast displays a general archaic morphology, although with some derived features associated with the spatial relationships with the face. A similar admixture was described for other Middle Pleistocene samples, like Sima de los Huesos. Future phylogenetic studies must re‐evaluate the facial skeleton to consider whether its features can be considered as related to the Neandertal lineage. Alternatively, they should be interpreted as the result of homoplasy and parallelism within the genus Homo, and may reflect a predominantly Asian variation. Am J Phys Anthropol 160:633–643, 2016. © 2016 Wiley Periodicals, Inc.

  March 12, 2016   doi: 10.1002/ajpa.22974   open full text
• Quantifying variation in human scalp hair fiber shape and pigmentation.
  Tina Lasisi, Shosuke Ito, Kazumasa Wakamatsu, Colin N. Shaw.
  American Journal of Physical Anthropology. March 09, 2016
  Objectives This study aims to evaluate the use of quantitative methods of measuring variation in scalp hair fiber shape and pigmentation and carry out exploratory data analysis on a limited sample of individuals from diverse populations in order to inform future avenues of research for the evolution of modern human hair variation. Methods Cross‐sectional area and shape and average curvature of scalp hair fibers were quantified using ImageJ. Pigmentation was analyzed using chemical methods estimating total melanin content through spectrophotometric methods, and eumelanin and pheomelanin content through HLPC analysis of melanin‐specific degradation products. Results The initial results reinforced findings from earlier, traditional studies. African and African Diaspora scalp hair was significantly curled, (East) Asian hair was significantly thick, and European hair was significantly lighter in color. However, pigmentation analyses revealed a high level of variability in the melanin content of non‐European populations and analysis of curvature found a large range of variation in the average curvature of East African individuals. Conclusions Overall, these results suggest the usefulness of chemical methods for the elucidation of nonperceptible differences in scalp hair color and highlight the need for improvements in our assessment and understanding of hair fiber curvature. Am J Phys Anthropol 160:341–352, 2016. © 2016 Wiley Periodicals, Inc.

  March 09, 2016   doi: 10.1002/ajpa.22971   open full text
• Variation in the human bicondylar angle.
  Erin B. Waxenbaum, Michala K. Stock.
  American Journal of Physical Anthropology. March 07, 2016
  Objectives Investigations of the human femoral bicondylar angle have largely focused on interspecific differences and intrapopulation variation. This analysis assesses the range of variation in the bicondylar angle in humans across four populations, examining the effects of population, sex and age. Materials and Methods The bicondylar angle was assessed in four sex‐ and age‐balanced adult skeletal samples—modern Terry Whites and Blacks and archaeological South Dakota Arikara and Native Alaskans. The overall range of variation was assessed, and variation specific to population, sex, and age analyzed through ANOVAs and post hoc Tukey's honestly significant difference tests. Results A one‐way ANOVA highlights a significant effect of population on bicondylar angle; however, the only significant difference occurs between the Terry White and South Dakota Arikara samples. Sex displays a significant effect for the total pooled sample; yet, within population, the effect of sex is significant only among South Dakota Arikara. Age also has a significant effect on bicondylar angle in the total sample; however, the interaction between age and population is not significant. Conclusion The results highlight the degree of variation in the bicondylar angle that exists intraspecifically. Differing degrees of variation due to sex suggest that sexual dimorphism is not universal in the human bicondylar angle. Furthermore, the broad impact of age on this feature is discussed, including the potential for plasticity through adulthood. By recognizing and explicitly examining morphological features that vary in human populations, we can appreciate the origins of variation and its implications for locomotor function, human diversity and evolutionary relationships. Am J Phys Anthropol 160:334–340, 2016. © 2016 Wiley Periodicals, Inc.

  March 07, 2016   doi: 10.1002/ajpa.22972   open full text
• Importance of the geographic barriers to promote gene drift and avoid pre‐ and post‐Columbian gene flow in Mexican native groups: Evidence from forensic STR Loci.
  Héctor Rangel‐Villalobos, Víctor Manuel Martínez‐Sevilla, Gabriela Martínez‐Cortés, José Alonso Aguilar‐Velázquez, Martha Sosa‐Macías, Rodrigo Rubi‐Castellanos, Antonio González‐Martín.
  American Journal of Physical Anthropology. March 04, 2016
  Objective To analyze the origin, structure, relationships, and recent admixture in Mexican Native groups based on 15 STRs commonly used in human identification. Methods We analyzed 39 Mexican Native population samples using STR databases based on the AmpFlSTR® Identifiler kit (n = 3,135), including Mexican‐Mestizos (admixed), European and African populations, as reference. Results Based upon effective population size (Ne) differences, Native groups were clustered into three regions: i) Center‐Southeast groups, characterized by larger Ne, migration rate (Nm), genetic diversity (He), and relative homogeneity principally in the Yucatan Peninsula; ii) Isolated southern groups from Chiapas and Oaxaca, characterized by lower Ne, Nm, and He (i.e. higher isolation and genetic differentiation); iii) North‐Northwest groups, which are similar to the previous group but are characterized by generating the widest gene flow barrier in the Pre‐Hispanic Mexican territory, and currently by elevated admixture in some northern Native groups. Despite the relative congruence between genetic relationships with cultural, linguistic, geographic criteria, these factors do not explain the present‐day population structure of Native groups, excepting in those linguistically related to the Mayan that show higher homogeneity. The Isolation by distance model was demonstrated at long distances (>1,500 km), whereas geographic isolation stands as a determining factor to avoid both non‐indigenous admixture and bottleneck processes. Conclusions Different dynamics of gene flow and drift were observed among Mexican Native groups, highlighting the geographic barriers (mountains, canyons and jungle regions) as the main factor differentiating Pre‐Hispanic populations, and eventually helping to avoid Post‐European contact admixture and population bottleneck. Am J Phys Anthropol 160:298–316, 2016. © 2016 Wiley Periodicals, Inc.

  March 04, 2016   doi: 10.1002/ajpa.22969   open full text
• Isotopic reconstructions of habitat change surrounding the extinction of Oreopithecus, the last European ape.
  Sherry V. Nelson, Lorenzo Rook.
  American Journal of Physical Anthropology. March 02, 2016
  Objective Oreopithecus bambolii was the last hominoid to survive in Europe. The purpose of this investigation was to reconstruct, through stable isotope analyses, Oreopithecus’ habitat, subsistence behavior, and changes in habitat that may have led to its extinction. Methods Carbon and oxygen stable isotopes from inorganic carbonate in tooth enamel from Oreopithecus and its contemporaneous faunas from localities in Tuscany and Sardinia were sampled. Also the fauna from localities in Tuscany shortly after Oreopithecus went extinct were sampled. Results Results indicated that Oreopithecus, compared with most modern hominoids, inhabited forests that probably had a more open canopy. At Tuscan localities, Oreopithecus yields some of the highest carbon isotope values but some of the lowest oxygen, suggesting a diet that may have included tubers or aquatic vegetation. Relatively higher oxygen values in Sardinia suggested that its diet included arboreal foods as well. Among modern and fossil hominoids, Oreopithecus only resembled chimpanzees living outside of rainforests. It also resembled Ardipithecus in carbon isotope values, suggesting possible similarities in feeding strategies concordant with shared skeletal features between Oreopithecus and early hominins. Isotope values from post‐Oreopithecus faunas indicated a shift to more forested conditions, unlike other hominoid extinctions associated with loss of forest. Conclusions Isotopic reconstructions of Oreopithecus’ habitat and changes associated with its extinction indicated that its paleoecology was unique among hominoids. However, these reconstructions also suggested that like other hominoids, Oreopithecus was susceptible to changes in seasonality of precipitation, and it may have used wetlands as a buffer to seasonal regimes. Am J Phys Anthropol 160:254–271, 2016. © 2016 Wiley Periodicals, Inc.

  March 02, 2016   doi: 10.1002/ajpa.22970   open full text
• Mechanical and metabolic interactions in cortical bone development.
  Courtney D. Eleazer, Rimantas Jankauskas.
  American Journal of Physical Anthropology. February 26, 2016
  Objectives Anthropological studies of cortical bone often aim to reconstruct either habitual activities or health of past populations. During development, mechanical loading and metabolism simultaneously shape cortical bone structure; yet, few studies have investigated how these factors interact. Understanding their relative morphological effects is essential for assessing human behavior from skeletal samples, as previous studies have suggested that interaction effects may influence the interpretation from cortical structure of physical activity or metabolic status. Material and Methods This study assesses cross‐sectional geometric and histomorphometric features in bones under different loading regimes (femur, humerus, rib) and compares these properties among individuals under different degrees of metabolic stress. The study sample consists of immature humans from a late medieval Lithuanian cemetery (Alytus, 14th–18th centuries AD). Analyses are based on the hypothesis that metabolic bone loss is distributed within the skeleton in a way that optimizes mechanical competency. Results Results suggest mechanical compensation for metabolic bone loss in the cross‐sectional properties of all three bones (especially ribs), suggesting a mechanism for conserving adequate bone strength for different loads across the skeleton. Microscopic bone loss is restricted to stronger bones under high loads, which may mitigate fracture risk in areas of the skeleton that are more resistive to loading, although alternative explanations are examined. Discussion Distributions of metabolic bone loss and subsequent structural adjustments appear to preserve strength. Nevertheless, both mechanics and metabolism have a detectable influence on morphology, and potential implications for behavioral interpretations in bioculturally stressed samples due to this interaction are explored. Am J Phys Anthropol 160:317–333, 2016. © 2016 Wiley Periodicals, Inc.

  February 26, 2016   doi: 10.1002/ajpa.22967   open full text
• Comparative analysis of dentognathic pathologies in the Dmanisi mandibles.
  Ann Margvelashvili, Christoph P.E. Zollikofer, David Lordkipanidze, Paul Tafforeau, Marcia S. Ponce de León.
  American Journal of Physical Anthropology. February 26, 2016
  Objectives Due to the scarcity of the fossil record, in vivo changes in the dentognathic system of early Homo are typically documented at the level of individual fossil specimens, and it remains difficult to draw population‐level inferences about dietary habits, diet‐related activities and lifestyle from individual patterns of dentognathic alterations. The Plio‐Pleistocene hominin sample from Dmanisi (Georgia), dated to 1.77 million years ago, offers a unique opportunity to study in vivo changes in the dentognathic system of individuals belonging to a single paleodeme of early Homo. Materials and Methods We analyze dentognathic pathologies in the Dmanisi sample, and in comparative samples of modern Australian and Greenlander hunter‐gatherer populations, applying clinical protocols of dentognathic diagnostics. Results The Dmanisi hominins exhibit a similarly wide diversity and similar incidence of dentognathic pathologies as the modern human hunter‐gatherer population samples investigated here. Dmanisi differs from the modern population samples in several respects: At young age tooth wear is already advanced, and pathologies are more prevalent. At old age, hypercementosis is substantial. Conclusions Results indicate that dentognathic pathologies and disease trajectories are largely similar in early Homo and modern humans, but that the disease load was higher in early Homo, probably as an effect of higher overall stress on the dentognathic system. Am J Phys Anthropol 160:229–253, 2016. © 2016 Wiley Periodicals, Inc.

  February 26, 2016   doi: 10.1002/ajpa.22966   open full text
• Population inference from contemporary American craniometrics.
  Bridget F.B. Algee‐Hewitt.
  American Journal of Physical Anthropology. February 19, 2016
  Objectives This analysis delivers a composite picture of population structure, admixture, ancestry variation, and personal identity in the United States, as observed through the lens of forensic anthropological casework and modern skeletal collections. It tests the applicability of the probabilistic clustering methods commonly used in human population genetics for the analysis of continuous, cranial measurement data, to improve population inference for admixed individuals without prior knowledge of sample origins. Materials and Methods The unsupervised model‐based clustering methods of finite mixture analysis are used here to reveal latent population structure and generate admixture proportions for craniofacial measurements from the Forensic Anthropology Data Bank (FDB). Craniometric estimates of ancestry are also generated under a three contributor model, sourcing parental reference populations from the Howells Craniometric Dataset. Tests of association are made among the coefficients of cluster memberships and the demographic information documented for each individual in the FDB. Clustering results are contextualized within the framework of conventional approaches to population structure analysis and individual ancestry estimation to discuss method compatibility. Results The findings reported here for contemporary American craniometrics are in agreement with the expected patterns of intergroup relationships, geographic origins and results from published genetic analyses. Discussion Population inference methods that allow for the model‐bound estimation of admixture and ancestry proportions from craniometric data not only enable parallel—skeletal and genetic—analyses but they are also shown to be more informative than those methods that perform hard classifications using externally‐imposed categories or seek to explain gross variation by low‐dimensional projections. Am J Phys Anthropol 160:604–624, 2016. © 2016 Wiley Periodicals, Inc.

  February 19, 2016   doi: 10.1002/ajpa.22959   open full text
• Dominance relationships in male Nepal gray langurs (Semnopithecus schistaceus).
  Rachel F. Perlman, Carola Borries, Andreas Koenig.
  American Journal of Physical Anthropology. February 19, 2016
  Objectives Reproductive skew is proposed to link to despotism in dominance hierarchies. While studies illustrating male skew are plentiful, demonstrating the link to despotism is rare. Likewise, it is often unknown which factors (e.g., resource holding potential, age, physical condition) affect a male's dominance rank. Here we investigated correlates of male rank and hierarchy characteristics in Nepal gray langurs (Semnopithecus schistaceus), a population with high male reproductive skew, and compared the results to other multi‐male groups of nonhuman primates. Methods We collected dyadic displacement interactions from two groups (mean 3.0 and 4.1 adult males) for five years each. We assessed dominance ranks for demographically stable phases (n = 11, n = 28) and analyzed the effects of age and physical condition through linear mixed models (LMM). We analyzed hierarchy characteristics via the program MatMan. We used data from 27 primate groups (cercopithecines, colobines, hominoids) as a comparative sample. Results The highest ranks were attained by adults in one group (LMM, P < 0.091) and by young adults in the other group (LMM, P < 0.001). With some exceptions, rank was highest for males with higher physical condition scores (LMM, P < 0.05). Hierarchies had high directional consistency (mean > 0.93) and linearity (mean >0.81) and were relatively steep (mean >0.66) when compared with other species. Discussion Dominance rank followed a pattern predicted by resource holding potential, but other individual attributes and group composition also seemed important. As predicted, hierarchy characteristics indicated a despotic system in line with the strong reproductive skew. Across primates, however, the degree of despotism did not appear to match the degree of reproductive skew. Am J Phys Anthropol 160:208–219, 2016. © 2016 Wiley Periodicals, Inc.

  February 19, 2016   doi: 10.1002/ajpa.22958   open full text
• Demographic differences between funerary caves and megalithic graves of northern Spanish Late Neolithic/Early Chalcolithic.
  Teresa Fernández‐Crespo, Concepción de‐la‐Rúa.
  American Journal of Physical Anthropology. February 17, 2016
  Objectives The study focuses on the estimation of demographic parameters of Late Neolithic/Early Chalcolithic (mid 4th‐early 3rd millenniums cal. BC) burial sites from the La Rioja region (Ebro valley, northern Spain) to identify demographic characteristics. Materials and Methods The human remains come from three caves (Las Yurdinas II, Peña Larga, and La Peña de Marañón) and three megalithic graves (Alto de la Huesera, San Martín, and Peña Guerra II). The total skeletal sample consists of a minimum of 261 individuals, 149 being buried in caves and 112 in megalithic graves. Data based on age and sex estimation are analyzed using abridged life tables, mortality rates, and sex ratios. Results A systematic bias against children under 5 years of age is detected both in caves (5q0 = 187.92%) and megalithic graves (5q0 = 71.43%) but also against some juveniles and adults compared with population models, though a statistically significant greater lack of infants is worth noting in the megaliths (t‐test, P = 0.012). Moreover, a significant divergence in sex ratios (χ2, P = 0.002) is also identified between site types, clearly prioritizing women in caves (sex ratio = 0.45) and men in megalithic graves (sex ratio = 1.33). Conclusions This evidence is interpreted as the result of different selective burial patterns. The mortuary variability could lie behind intragroup differential status relationships, though the hypothesis of two populations performing distinct funerary practices in a small region cannot be rejected at the present state of the research. Am J Phys Anthropol 160:284–297, 2016. © 2016 Wiley Periodicals, Inc.

  February 17, 2016   doi: 10.1002/ajpa.22963   open full text
• Nutritional consequences of folivory in a small‐bodied lemur (Lepilemur leucopus): Effects of season and reproduction on nutrient balancing.
  Iris Dröscher, Jessica M. Rothman, Jörg U. Ganzhorn, Peter M. Kappeler.
  American Journal of Physical Anthropology. February 11, 2016
  Objectives Small‐bodied folivores are rare because processing leaves often requires extensive gut adaptations and lengthy retention times for fiber fermentation. However, the <1 kg nocturnal white‐footed sportive lemurs (Lepilemur leucopus) persist on a leaf‐based diet. We investigated how extrinsic (i.e., seasonality in temperature and food availability) and intrinsic factors (i.e., reproductive state) influence nutrient intake and explored how nutrient and energy needs are met in this species. Materials and Methods We conducted full night focal follows across all seasons and analyzed nutrients in all items eaten by adults of both sexes to investigate nutrient intake and nutritional priorities in L. leucopus. We estimated digestible protein content, as this is a biologically more meaningful measure than crude protein. Results Protein intake was constant across seasons, while non‐protein energy and dry matter intake increased from the hot wet to the cold dry season. Males and females did not differ in their nutrient or apparent energy intake irrespective of female reproductive state. Discussion We conclude that these animals prioritize protein over non‐protein energy intake as dietary protein is in limited supply, and that thermoregulation poses higher energetic costs than reproduction in this species. While protein intake did not differ across female reproductive states, the relative protein content of the diet was highest during the lactation period, indicating that the balance of non‐protein to protein intake may be more important than absolute intake. Dry matter intake was high compared to other folivorous primates, indicating that L. leucopus follows an intake rather than an efficiency strategy to meet its energy requirements. Am J Phys Anthropol 160:197–207, 2016. © 2016 Wiley Periodicals, Inc.

  February 11, 2016   doi: 10.1002/ajpa.22952   open full text
• Frailty and famine: Patterns of mortality and physiological stress among victims of famine in medieval London.
  Samantha L. Yaussy, Sharon N. DeWitte, Rebecca C. Redfern.
  American Journal of Physical Anthropology. February 08, 2016
  Objectives Famine can be defined as a shortage of foodstuffs that instigates widespread excess mortality due to starvation, infectious disease, and social disruption. Like other causes of catastrophic mortality, famine has the potential to be selective. This study examines how famines in medieval London were selective with respect to previous stress, age, and sex. Methods This study compares famine burials to nonfamine (attritional) burials from the St Mary Spital cemetery, London (c. 1120–1540 AD). We evaluate the associations between age, sex, and skeletal stress indicators [cribra orbitalia, linear enamel hypoplasia (LEH), and periosteal lesions] using hierarchical log‐linear analysis. Additionally, sex is modeled as a covariate affecting the Gompertz hazard of mortality. Results Significant associations exist between famine burials and LEH and between attritional burials and periosteal lesions, independent of age or sex. Sex did not significantly affect risk of mortality in the 12th–13th centuries. However, males interred in attritional burials c. 1400–1539 AD faced a lower risk of mortality compared to females. Discussion The LEH results suggest that early exposure to stressors increased frailty in the context of famine. The periosteal lesion results suggest that individuals were more likely to survive stressors and thus form these lesions under nonfamine conditions. Hazard analysis suggests that a cultural or biological transformation during this period affected sex differences in mortality. Possible causes include the selective mortality during the Black Death, which might have influenced risks of mortality among survivors, or unequal distribution of improvements in standards of living after the epidemic. Am J Phys Anthropol 160:272–283, 2016. © 2016 Wiley Periodicals, Inc.

  February 08, 2016   doi: 10.1002/ajpa.22954   open full text
• Random genetic drift, natural selection, and noise in human cranial evolution.
  Charles C. Roseman.
  American Journal of Physical Anthropology. January 28, 2016
  Objectives This study assesses the extent to which relationships among groups complicate comparative studies of adaptation in recent human cranial variation and the extent to which departures from neutral additive models of evolution hinder the reconstruction of population relationships among groups using cranial morphology. Materials and Methods Using a maximum likelihood evolutionary model fitting approach and a mixed population genomic and cranial data set, I evaluate the relative fits of several widely used models of human cranial evolution. Moreover, I compare the goodness of fit of models of cranial evolution constrained by genomic variation to test hypotheses about population specific departures from neutrality. Results Models from population genomics are much better fits to cranial variation than are traditional models from comparative human biology. There is not enough evolutionary information in the cranium to reconstruct much of recent human evolution but the influence of population history on cranial variation is strong enough to cause comparative studies of adaptation serious difficulties. Deviations from a model of random genetic drift along a tree‐like population history show the importance of environmental effects, gene flow, and/or natural selection on human cranial variation. Moreover, there is a strong signal of the effect of natural selection or an environmental factor on a group of humans from Siberia. Discussion The evolution of the human cranium is complex and no one evolutionary process has prevailed at the expense of all others. A holistic unification of phenome, genome, and environmental context, gives us a strong point of purchase on these problems, which is unavailable to any one traditional approach alone. Am J Phys Anthropol 160:582–592, 2016. © 2016 Wiley Periodicals, Inc.

  January 28, 2016   doi: 10.1002/ajpa.22918   open full text
• A mixed model for the relationship between climate and human cranial form.
  David C. Katz, Mark N. Grote, Timothy D. Weaver.
  American Journal of Physical Anthropology. December 02, 2015
  Objectives We expand upon a multivariate mixed model from quantitative genetics in order to estimate the magnitude of climate effects in a global sample of recent human crania. In humans, genetic distances are correlated with distances based on cranial form, suggesting that population structure influences both genetic and quantitative trait variation. Studies controlling for this structure have demonstrated significant underlying associations of cranial distances with ecological distances derived from climate variables. However, to assess the biological importance of an ecological predictor, estimates of effect size and uncertainty in the original units of measurement are clearly preferable to significance claims based on units of distance. Unfortunately, the magnitudes of ecological effects are difficult to obtain with distance‐based methods, while models that produce estimates of effect size generally do not scale to high‐dimensional data like cranial shape and form. Methods Using recent innovations that extend quantitative genetics mixed models to highly multivariate observations, we estimate morphological effects associated with a climate predictor for a subset of the Howells craniometric dataset. Results Several measurements, particularly those associated with cranial vault breadth, show a substantial linear association with climate, and the multivariate model incorporating a climate predictor is preferred in model comparison. Conclusions Previous studies demonstrated the existence of a relationship between climate and cranial form. The mixed model quantifies this relationship concretely. Evolutionary questions that require population structure and phylogeny to be disentangled from potential drivers of selection may be particularly well addressed by mixed models. Am J Phys Anthropol 160:593–603, 2016. © 2015 Wiley Periodicals, Inc.

  December 02, 2015   doi: 10.1002/ajpa.22896   open full text
• Sex, Ancestral, and pattern type variation of fingerprint minutiae: A forensic perspective on anthropological dermatoglyphics.
  Nichole A. Fournier, Ann H. Ross.
  American Journal of Physical Anthropology. September 23, 2015
  Objectives The majority of anthropological studies on dermatoglyphics examine the heritability and inter‐population variation of Level 1 detail (e.g., pattern type, total ridge count), while forensic scientists concentrate on individual uniqueness of Level 2 and 3 detail (e.g., minutiae and pores, respectively) used for positive identification. The present study bridges the gap between researcher–practitioner by examining sex, ancestral, and pattern type variation of Level 2 detail (e.g., minutiae). Materials and Methods Bifurcations, ending ridges, short ridges, dots, and enclosures on the right index finger of 243 individuals (n = 61 African American ♀; n = 61 African American ♂; n = 61 European American ♀; n = 60 European American ♂) were analyzed. The overall effect of sex, ancestry, and pattern type on minutiae variation was assessed using a MANCOVA. ANOVA was used to identify Level 2 detail variables responsible for the variation. Logistic regression was used to classify individuals into groups. Results The effect of sex is insignificant. Ancestry is significant (Wilks' λ = 0.053 F value = 2.98, DF = 4,224, P value = 0.02), as is pattern type (Wilks' λ = 0.874 F value = 2.57, DF = 12,592.94, P value = 0.003). The ANOVA reveals that bifurcations are responsible for the variation between ancestral groups, while bifurcations and ending ridges vary between patterns. Logistic regression results suggest that total bifurcations can predict the ancestry of an individual (ChiSq = 6.55, df = 1, Prob > ChiSq = 0.01). Discussion Significant minutiae variation between ancestral groups yields information that is valuable in both a forensic and anthropological setting. Am J Phys Anthropol 160:625–632, 2016. © 2015 Wiley Periodicals, Inc.

  September 23, 2015   doi: 10.1002/ajpa.22869   open full text
• Quantitative assessment of skin, hair, and iris variation in a diverse sample of individuals and associated genetic variation.
  Heather L. Norton, Melissa Edwards, S. Krithika, Monique Johnson, Elizabeth A. Werren, Esteban J. Parra.
  American Journal of Physical Anthropology. September 10, 2015
  Objectives The main goals of this study are to 1) quantitatively measure skin, hair, and iris pigmentation in a diverse sample of individuals, 2) describe variation within and between these samples, and 3) demonstrate how quantitative measures can facilitate genotype‐phenotype association tests. Materials and Methods We quantitatively characterize skin, hair, and iris pigmentation using the Melanin (M) Index (skin) and CIELab values (hair) in 1,450 individuals who self‐identify as African American, East Asian, European, Hispanic, or South Asian. We also quantify iris pigmentation in a subset of these individuals using CIELab values from high‐resolution iris photographs. We compare mean skin M index and hair and iris CIELab values among populations using ANOVA and MANOVA respectively and test for genotype‐phenotype associations in the European sample. Results All five populations are significantly different for skin (P <2 × 10−16) and hair color (P <2 × 10−16). Our quantitative analysis of iris and hair pigmentation reinforces the continuous, rather than discrete, nature of these traits. We confirm the association of three loci (rs16891982, rs12203592, and rs12913832) with skin pigmentation and four loci (rs12913832, rs12203592, rs12896399, and rs16891982) with hair pigmentation. Interestingly, the derived rs12203592 T allele located within the IRF4 gene is associated with lighter skin but darker hair color. Discussion The quantitative methods used here provide a fine‐scale assessment of pigmentation phenotype and facilitate genotype‐phenotype associations, even with relatively small sample sizes. This represents an important expansion of current investigations into pigmentation phenotype and associated genetic variation by including non‐European and admixed populations. Am J Phys Anthropol 160:570–581, 2016. © 2015 Wiley Periodicals, Inc.

  September 10, 2015   doi: 10.1002/ajpa.22861   open full text
• Fire and home range expansion: A behavioral response to burning among savanna dwelling vervet monkeys (Chlorocebus aethiops).
  Nicole M. Herzog, Christopher H. Parker, Earl R. Keefe, James Coxworth, Alan Barrett, Kristen Hawkes.
  American Journal of Physical Anthropology. June 02, 2014
  The behavioral adaptations of primates to fire‐modified landscapes are of considerable interest to anthropologists because fire is fundamental to life in the African savanna—the setting in which genus Homo evolved. Here we report the behavioral responses of a savanna‐dwelling primate, vervet monkeys (Chlorocebus aethiops), to fire‐induced ecological change. Using behavioral and spatial data to characterize ranging patterns prior to and postburn and between burn and nonburn years, we show that these primates inhabiting small, spatially bound, riverine habitats take advantage of newly burned savanna landscapes. When subjects encountered controlled fires, they did not flee but instead avoided the path of the fire seemingly unbothered by its approach. After fire, the primates' home range expanded into newly burned but previously unused areas. These results contribute to understanding the response of non‐human primates to fire‐modified landscapes and can shed light on the nature and scope of opportunities and constraints posed by the emergence of fire‐affected landscapes in the past. Results also expose deficiencies in our knowledge of fire‐related behavioral responses in the primate lineage and highlight the need for further investigation of these responses as they relate to foraging opportunities, migration, resource use, and especially fire‐centric adaptations in our own genus. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  June 02, 2014   doi: 10.1002/ajpa.22550   open full text
• C4‐consumers in southern europe: The case of friuli V.G. (NE‐Italy) during early and central middle ages.
  P. Iacumin, E. Galli, F. Cavalli, L. Cecere.
  American Journal of Physical Anthropology. June 02, 2014
  Isotope variations were studied in necropolises of the early (6th to 7th century CE) and central (10th to 11th century CE) medieval period located in Fruili‐Venezia Giulia (Northeastern Italy). The two periods each shortly followed two great barbarian invasions that changed the politics and economy of Italy: the arrivals of Langobards in 578 CE and the Hungarian incursions from the end of the 9th to the first half of the 10th century. These events had a tragic effect on the economy of Friuli‐Venezia Giulia: severe depopulation and the partial abandonment of the countryside with fall of agricultural production. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  June 02, 2014   doi: 10.1002/ajpa.22553   open full text
• Canalization and developmental instability of the fetal skull in a mouse model of maternal nutritional stress.
  Paula N. Gonzalez, Federico P. Lotto, Benedikt Hallgrímsson.
  American Journal of Physical Anthropology. May 29, 2014
  Nutritional imbalance is one of the main sources of stress in both extant and extinct human populations. Restricted availability of nutrients is thought to disrupt the buffering mechanisms that contribute to developmental stability and canalization, resulting in increased levels of fluctuating asymmetry (FA) and phenotypic variance among individuals. However, the literature is contradictory in this regard. This study assesses the effect of prenatal nutritional stress on FA and among‐individual variance in cranial shape and size using a mouse model of maternal protein restriction. Two sets of landmark coordinates were digitized in three dimensions from skulls of control and protein restricted specimens at E17.5 and E18.5. We found that, by the end of gestation, maternal protein restriction resulted in a significant reduction of skull size. Fluctuating asymmetry in size and shape exceeded the amount of measurement error in all groups, but no significant differences in the magnitude of FA were found between treatments. Conversely, the pattern of shape asymmetry was affected by the environmental perturbation since the angles between the first eigenvectors extracted from the covariance matrix of shape asymmetric component of protein restricted and control groups were not significantly different from the expected for random vectors. In addition, among‐individual variance in cranial shape was significantly higher in the protein restricted than the control group at E18.5. Overall, the results obtained from a controlled experiment do not support the view of fluctuating asymmetry of cranial structures as a reliable index for inferring nutritional stress in human populations. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 29, 2014   doi: 10.1002/ajpa.22545   open full text
• Water consumption in Iron Age, Roman, and Early Medieval Croatia.
  E. Lightfoot, M. Šlaus, T.C. O'Connell.
  American Journal of Physical Anthropology. May 29, 2014
  Patterns of water consumption by past human populations are rarely considered, yet drinking behavior is socially mediated and access to water sources is often socially controlled. Oxygen isotope analysis of archeological human remains is commonly used to identify migrants in the archeological record, but it can also be used to consider water itself, as this technique documents water consumption rather than migration directly. Here, we report an oxygen isotope study of humans and animals from coastal regions of Croatia in the Iron Age, Roman, and Early Medieval periods. The results show that while faunal values have little diachronic variation, the human data vary through time, and there are wide ranges of values within each period. Our interpretation is that this is not solely a result of mobility, but that human behavior can and did lead to human oxygen isotope ratios that are different from that expected from consumption of local precipitation. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 29, 2014   doi: 10.1002/ajpa.22544   open full text
• Intra‐population variation in anemia status and its relationship to economic status and self‐perceived health in the Mexican family life survey: Implications for bioarchaeology.
  Barbara A. Piperata, Mark Hubbe, Kammi K. Schmeer.
  American Journal of Physical Anthropology. May 27, 2014
  Recently scholars have advocated for the use of a critical biocultural approach in bioarchaeology, where osteological and dental markers of stress are used to understand the broader biosocial context of past populations. However, the ability to accomplish this task rests on the assumption that ultimate‐level environmental stressors and well‐being in the past can be reconstructed from the prevalence of pathologies in skeletal collections. Here we test this assumption using anemia prevalence in the Mexican Family Life Survey. Specifically we test three hypotheses: (1) that individuals sharing the same household are more likely to share anemia status; (2) anemia status is a predictor of economic status (a common proxy for broader environmental context); and (3) anemia status is related to self‐rated health. Results demonstrate that: anemia status was not commonly shared between household members; there was a significant overlap in economic status between anemic and nonanemic individuals (i.e., anemia poorly predicted economic status) and; while anemia status was associated with self‐perceived health, the majority of those who reported poor health were nonanemic while a significant number of those who reported very good health were anemic. We argue that these findings are likely related to variation in individual frailty, which is shaped by biological and cultural risk factors. Therefore, we advocate for greater incorporation of individual frailty into bioarchaeological investigations, and, in effort to overcome some of the difficulties associated with this task, increased use of data from living populations and greater collaboration between bioarchaeologists and human biologists. Am J Phys Anthropol :1–11, 2014. © 2014 Wiley Periodicals, Inc.

  May 27, 2014   doi: 10.1002/ajpa.22543   open full text
• Mapping bone cell distributions to assess ontogenetic origin of primate midfacial form.
  Timothy D. Smith, Ethan S. Kentzel, Jayna M. Cunningham, Amanda E. Bruening, Kathryn D. Jankord, Sara J. Trupp, Christopher J. Bonar, Susan J. Rehorek, Valerie B. DeLeon.
  American Journal of Physical Anthropology. May 24, 2014
  Midfacial reduction in primates has been explained as a byproduct of other growth patterns, especially the convergent orbits. This is at once an evolutionary and developmental explanation for relatively short snouts in most modern primates. Here, we use histological sections of perinatal nonhuman primates (tamarin, tarsier, loris) to investigate how orbital morphology emerges during ontogeny in selected primates compared to another euarchontan (Tupaia glis). We annotated serial histological sections for location of osteoclasts or osteoblasts, and used these to create three‐dimensional “modeling maps” showing perinatal growth patterns of the facial skeleton. In addition, in one specimen we transferred annotations from histological sections to CT slices, to create a rotatable 3D volume that shows orbital modeling. Our findings suggest that growth in the competing orbital and neurocranial functional matrices differs among species, influencing modeling patterns. Distinctions among species are observed in the frontal bone, at a shared interface between the endocranial fossa and the orbit. The medial orbital wall is extensively resorptive in primates, whereas the medial orbit is generally depositional in Tupaia. As hypothesized, the orbital soft tissues encroach on available interorbital space. However, eye size cannot, by itself, explain the extent of reduction of the olfactory recess. In Loris, the posterior portion of medial orbit differed from the other primates. It showed evidence of outward drift where the olfactory bulb increased in cross‐sectional area. We suggest the olfactory bulbs are significant to orbit position in strepsirrhines, influencing an expanded interorbital breadth at early stages of development. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 24, 2014   doi: 10.1002/ajpa.22540   open full text
• Fluorescence methods (VistaCam iX proof and DIAGNODent pen) for the detection of occlusal carious lesions in teeth recovered from archaeological context.
  Jacek Tomczyk, Julian Komarnitki, Marta Zalewska, Tomasz Lekszycki, Dorota Olczak‐Kowalczyk.
  American Journal of Physical Anthropology. May 24, 2014
  Diagnosis of occlusal enamel caries in archaeologically derived collections remains a controversial problem because the accumulation of contaminants in fissures can interfere with diagnosis. Certain novel light‐induced fluorescence methods, such as the DIAGNODent pen 2190 (DD) and VistaCam iX Proof (VC), have been used to detect dental caries in clinical settings. In this study, the abilities of DD and VC to detect initial enamel caries in archaeologically derived material is determined and compared with those of other methods (visual inspection, X‐ray, histology, and micro‐CT). Dental material encompassing the remains of 58 individuals, including a total of 380 teeth from each of three historical periods: modern Islamic (AD 1850–1950), Islamic (AD 600–1200) and late Roman (AD 200–400), obtained from two archaeological sites (Terqa and Tell Masaikh) located in the Middle Euphrates valley (Syria), were analyzed. VC was found to have excellent sensitivity (98), while DD obtained lower sensitivity (76) in detecting dental caries in its early stages. The results obtained by VC and micro‐CT, considered the most reliable imaging technique, were not statistically significant (P = 0.3068). By contrast, results obtained by DD and micro‐CT results, and DD and VC results were statistically significant (P < 0.0001, P = 0.0015, respectively). However the presence of dirt, stain, calculus, and plaque in the pits and fissures of the occlusal surface compromise correct diagnosis of caries by VC and DD. Consequently, for teeth recovered from archaeological contexts where staining, calculus and plaque are present, the best solution remains micro‐CT. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 24, 2014   doi: 10.1002/ajpa.22542   open full text
• Temporal trends in femoral diaphyseal torsional asymmetry among the Arikara associated with postural behavior.
  Daniel J. Wescott, Deborah L. Cunningham, David R. Hunt.
  American Journal of Physical Anthropology. May 24, 2014
  Average femoral torsion has been reported to differ among populations, and several studies have observed a relatively high prevalence of femoral anteversion asymmetry in Native Americans, especially females. This study investigates sexual dimorphism and temporal trends in femoral torsional asymmetry among the Arikara from the seventeenth to the early nineteenth century. To establish if there are population differences, femoral torsion was first measured using a direct method on a diverse comparative sample of Native Americans from the Southwest, Midwest, and Great Plains as well as American Whites and Blacks. To examine temporal trends among the Arikara, femoral torsion was examined using the orientation of the maximum bending rigidity at subtrochanteric in 154 females and 164 males from three temporal variants of the Arikara Coalescent tradition. There is significant sexual dimorphism in femoral torsional directional and absolute asymmetry among most Native American samples, but not among American Whites and Blacks. Among the Arikara there is significant sexual dimorphism in femoral torsional asymmetry in all three temporal variants, and asymmetry in femoral torsional asymmetry increased significantly from the protohistoric to the early historic period among females. The increased femoral torsional asymmetry is likely associated with a common side‐sitting posture observed in historic photographs of Great Plains females. Historic Arikara females may have habitually sat in this compulsory position for extended periods while conducting domestic chores. The dramatic change from the protohistoric to historic period suggests a cultural change in sitting posture among females that was widespread across the Northern Plains. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 24, 2014   doi: 10.1002/ajpa.22541   open full text
• The ontogeny of talo‐crural appositional articular morphology among catarrhine taxa: Adult shape reflects substrate use.
  Kevin Turley, Stephen R. Frost.
  American Journal of Physical Anthropology. May 20, 2014
  The upper ankle joint forms a single articular plane between organism and the foot and substrate. Singular warp analysis shows that its shape reflects substrate use. This study explores whether the differences in shape are genetic with a developmental trajectory evident during ontogeny or epigenetic and the result of substrate use by the individual. A total of 418 matched distal tibial and proximal talar landmarked surfaces from adult and subadult specimens from 12 diverse catarrhine taxa were studied. Specimens were grouped by molar eruption (M1, M2, and M3) for comparative analysis. Generalized Procrustes analysis, multivariate regression, relative warp analysis, singular warp analysis, and permutation tests were used. Singular warp analysis for the entire cohort was highly significant in the first singular warp, with the adult taxa sorting by substrate use. All 173 subadults clustered with an adult “arboreal” shape profile. Among Hominoidea, adults (M3) sorted by substrate use with Pan paniscus and Hylobatidae assuming an “arboreal” shape separate from Pan troglodytes and the remaining taxa with “terrestrial” shape. Cercopithecoid adults sorted by substrate use as well, with the M3 specimens of Papio hamadryas and Macaca thibetana demonstrating a “terrestrial” shape. Differences in mode of locomotion did not affect the findings in the first singular warp. Results confirmed the convergence of talo‐crural shape among superfamilies based on substrate use and divergence in shape within Pan and Macaca, based on substrate use. The shape differences among adults (M3) are consistent with a plastic response to the behavioral stimulus of substrate use. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 20, 2014   doi: 10.1002/ajpa.22528   open full text
• Quantifying asymmetry: Ratios and alternatives.
  Erin M. Franks, Luis L. Cabo.
  American Journal of Physical Anthropology. May 20, 2014
  Traditionally, the study of metric skeletal asymmetry has relied largely on univariate analyses, utilizing ratio transformations when the goal is comparing asymmetries in skeletal elements or populations of dissimilar dimensions. Under this approach, raw asymmetries are divided by a size marker, such as a bilateral average, in an attempt to produce size‐free asymmetry indices. Henceforth, this will be referred to as “controlling for size” (see Smith: Curr Anthropol 46 (2005) 249‐273). Ratios obtained in this manner often require further transformations to interpret the meaning and sources of asymmetry. This model frequently ignores the fundamental assumption of ratios: the relationship between the variables entered in the ratio must be isometric. Violations of this assumption can obscure existing asymmetries and render spurious results. In this study, we examined the performance of the classic indices in detecting and portraying the asymmetry patterns in four human appendicular bones and explored potential methodological alternatives. Examination of the ratio model revealed that it does not fulfill its intended goals in the bones examined, as the numerator and denominator are independent in all cases. The ratios also introduced strong biases in the comparisons between different elements and variables, generating spurious asymmetry patterns. Multivariate analyses strongly suggest that any transformation to control for overall size or variable range must be conducted before, rather than after, calculating the asymmetries. A combination of exploratory multivariate techniques, such as Principal Components Analysis, and confirmatory linear methods, such as regression and analysis of covariance, appear as a promising and powerful alternative to the use of ratios. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 20, 2014   doi: 10.1002/ajpa.22539   open full text
• Bone quality in prehistoric, cis‐baikal forager femora: A micro‐CT analysis of cortical canal microstructure.
  Kathleen Faccia, Helen Buie, Andrzej Weber, Vladimir I. Bazaliiskii, Olga I. Goriunova, Steven Boyd, Benedikt Hallgrímsson, M. Anne Katzenberg.
  American Journal of Physical Anthropology. May 19, 2014
  Bone quality, a contributor to bone strength, is determined by structural and mechanical properties, which may be analyzed by gross and/or microscopic methods. Variables that contribute to bone quality, such as porosity, can provide insight into the health and lifestyles of people in prehistory. This study tests the ability of microcomputed tomography (µCT) to capture and characterize cortical canal systems in archaeological bone. Seven variables and 71 femora are analyzed to explore bone dynamics in prehistoric foragers from Lake Baikal, Siberia. The results indicate that canal number and canal separation differ significantly (P < 0.05) between age‐at‐death categories, but only for the pooled and male samples. When merged into a new variable by means of principal components analysis, canal diameter and canal surface to canal volume are also able to discriminate amongst age‐at‐death categories, as well as between the sexes. However, the overall lack of significant differences between the sexes and amongst age‐at‐death categories indicates that Baikal forager bone quality (i.e., canal architecture) did not change drastically throughout the lifespan. Interestingly, principal component one identified an untested variable that contributes to canal microstructure variability, and a sexual division of labor may promote divergent trends in canal degree of anisotropy between the sexes. Overall, µCT provides an alternate method for exploring bone quality in archaeological remains, complementing existing methods such as thin‐sectioning and gross morphological analyses. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 19, 2014   doi: 10.1002/ajpa.22533   open full text
• Birth is but our death begun: A bioarchaeological assessment of skeletal emaciation in immature human skeletons in the context of environmental, social, and subsistence transition.
  Gwen Robbins Schug, Haviva M. Goldman.
  American Journal of Physical Anthropology. May 17, 2014
  The second millennium BC was a period of significant social and environmental changes in prehistoric India. After the disintegration of the Indus civilization, in a phase known as the Early Jorwe (1400–1000 BC), hundreds of agrarian villages flourished in the Deccan region of west‐central India. Environmental degradation, combined with unsustainable agricultural practices, contributed to the abandonment of many communities around 1000 BC. Inamgaon was one of a handful of villages to persist into the Late Jorwe phase (1000–700 BC), wherein reliance on dry‐plough agricultural production declined. Previous research demonstrated a significant decline in body size (stature and body mass index) through time, which is often used to infer increased levels of biocultural stress in bioarchaeology. This article assesses evidence for growth disruption in the immature human skeletal remains from Inamgaon by correlating measures of whole bone morphology with midshaft femur compact bone geometry and histology. Growth derangement is observable in immature archaeological femora as an alteration in the expected amount and distribution of bone mass and porosity in the midshaft cross‐section. Cross‐section shape matched expectations for older infants with the acquisition of bipedal locomotion. These results support the hypothesis that small body size was related to disruptions in homeostasis and high levels of biocultural stress in the Late Jorwe at Inamgaon. Further, the combined use of geometric properties and histological details provides a method for teasing apart the complex interactions among activity and “health,” demonstrating how biocultural stressors affect the acquisition and quality of bone mass. Am J Phys Anthropol :1–17, 2014. © 2014 Wiley Periodicals, Inc.

  May 17, 2014   doi: 10.1002/ajpa.22536   open full text
• Patterns in ritual tooth avulsion at Roonka.
  Arthur C. Durband, Judith Littleton, Keryn Walshe.
  American Journal of Physical Anthropology. May 14, 2014
  Tooth avulsion is the intentional removal of one or more teeth for ritual or aesthetic reasons, or to denote group affiliation. Typically the maxillary incisors are the teeth most often selected for removal. Previous authors have discussed the presence of tooth avulsions in several individuals recovered from Roonka, but those papers did not examine any patterns in those removals that might be present. Analysis of the tooth avulsions at Roonka reveals a change in the practice over time, with the older burials from phase II typically showing removal of both maxillary central incisors with a left side bias when only one tooth is removed, and the more recent phase III burials showing only one incisor avulsed and a right side bias for removal. Frequencies in the practice also changed over time, with avulsions being much more common in the older phase II burials. Historical evidence suggests that any particular regional or social group would have its own particular pattern of tooth avulsion, so these changes in tooth avulsions at Roonka suggest that the site was either used by multiple groups of people for burials, or that there was significant cultural change during the occupation of the site. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 14, 2014   doi: 10.1002/ajpa.22531   open full text
• Mandibular development in Australopithecus robustus.
  Zachary Cofran.
  American Journal of Physical Anthropology. May 13, 2014
  Australopithecus robustus has a distinct mandibular anatomy, with a broad and deep corpus and a tall, relatively upright ramus. How this anatomy arose through development is unknown, as gross mandibular size and shape change have not been thoroughly examined quantitatively in this species. Herein, I investigate A. robustus mandibular growth by comparing its ontogenetic series with a sample of recent humans, examining age‐related size variation in 28 linear measurements. Resampling is used to compare the amount of proportional size change occurring between tooth eruption stages in the small and fragmentary A. robustus sample, with that of a more complete human skeletal population. Ontogenetic allometry of corpus robusticity is also assessed with least squares regression. Results show that nearly all measurements experience greater average increase in A. robustus than in humans. Most notably, A. robustus corpus breadth undergoes a spurt of growth before eruption of M1, likely due in part to delayed resorption of the ramus root on the lateral corpus. Between the occlusion of M1 and M2, nearly all dimensions experience greater proportional size change in A. robustus. Nested resampling analysis affirms that this pattern of growth differences between species is biologically significant, and not a mere byproduct of the fossil sample size. Some species differences are likely a function of postcanine megadontia in A. robustus, although the causes of other differences are less clear. This study demonstrates an important role of the postnatal period for mandibular shape development in this species. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 13, 2014   doi: 10.1002/ajpa.22527   open full text
• Sex of preceding sibling and anthropometrics of subsequent offspring at birth and in young adulthood: A population‐based study in Sweden.
  Aline Jelenkovic, Karri Silventoinen, Per Tynelius, Samuli Helle, Finn Rasmussen.
  American Journal of Physical Anthropology. May 13, 2014
  In many mammal species with sexual dimorphism producing sons is energetically more demanding to the mother than producing daughters. Although some studies in humans have suggested that offspring born after a brother have a smaller birth weight and adult height when compared with those born after a sister, little is known about this intergenerational cost of producing sons. We aimed to study whether the sex of preceding sibling is associated with anthropometrics of the subsequent child at birth and in young adulthood. This population‐based study was carried out on two data sets derived from the Swedish registers. Information on birth weight and length was obtained for 752,723 children of both sexes. Adult weight, height and muscle strength were available for 506,326 men. Multiple linear regression analyses showed that boys and girls born after a brother were, respectively, 18 and 9 g lighter and 0.08 and 0.03 cm (P < 0.001) shorter at birth than those born after a sister. Adjustment for gestational age decreased the magnitude of the associations [10 g and 0.04 cm (P < 0.001) in men and nonsignificant estimates in women], suggesting that part of the lower mean birth weight and length of individuals born after a brother was due to a shorter gestation. In young adulthood, men with a preceding brother showed 0.16 kg more in weight, 0.3% higher body mass index (P < 0.001) and a trend towards reduced height and muscle strength. Our results suggest that even though the sex of the previous child is associated with the anthropometrics of the subsequent child, the effect sizes are very small questioning whether this mechanism has adaptive value in contemporary humans. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 13, 2014   doi: 10.1002/ajpa.22534   open full text
• Dietary variation and food hardness in sooty mangabeys (Cercocebus atys): Implications for fallback foods and dental adaptation.
  W. Scott McGraw, Anna E. Vick, David J. Daegling.
  American Journal of Physical Anthropology. May 09, 2014
  We present information on food hardness and monthly dietary changes in female sooty mangabeys (Cercocebus atys) in Tai Forest, Ivory Coast to reassess the hypothesis that thick molar enamel is parsimoniously interpreted as a response to consumption of hard foods during fallback periods. We demonstrate that the diet of sooty mangabeys varies seasonally, but that one food—Sacoglottis gabonensis—is the most frequently consumed food every month and year round. This food is the hardest item in the sooty diet. Given that this species has among the thickest enamel within the primate order, a plausible conclusion is that thick enamel in this taxon evolved not in response to seasonally critical function or fallback foods, but rather to the habitual, year round processing of a mechanically protected foodstuff. These data serve as a caution against de rigueur interpretations that reliance on fallback foods during lean periods primarily explains the evolution of thick enamel in primates. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 09, 2014   doi: 10.1002/ajpa.22525   open full text
• Locals, resettlers, and pilgrims: A genetic portrait of three pre‐Columbian Andean populations.
  Mateusz Baca, Martyna Molak, Maciej Sobczyk, Piotr Węgleński, Anna Stankovic.
  American Journal of Physical Anthropology. May 06, 2014
  The common practice of resettlement and the development of administrative and ceremonial systems shaped the population landscape of the Andean region under the Inca rule. The area surrounding Coropuna and Solimana volcanoes, in the Arequipa region (Peru), carried a high‐density, multiethnic population. We studied the genetic variation among three pre‐Columbian populations from three functionally diverse archaeological sites excavated in this region. By analyzing the genetic composition of a large ceremonial center (Acchaymarca), an isolated pastoral settlement (Tompullo 2), and an agricultural settlement characterized by architectural features rare in the region (Puca), we investigated the patterns of population movements and the distribution of genetic diversity. We obtained mitochondrial DNA sequences for 25 individuals and autosomal microsatellite profiles for 20 individuals from Acchaymarca and Puca sites. These were compared with previously published genetic data for Tompullo 2 and other pre‐Columbian populations. We found differences among the genetic portraits of the three populations, congruent with the archaeologically described functions and characteristics of the sites. The Acchaymarca population had the highest genetic diversity and possessed the lowest number of unique mtDNA haplotypes. The Tompullo 2 population exhibited the lowest level of genetic diversity. The Puca population was distinct from the other two populations owing to a high frequency of haplogroup A haplotypes, what potentially explains the non‐local character of the burial architecture. Our analyses of microsatellite data suggest that gene flow between sites was mostly mediated by females, which is consistent with ethnohistorical knowledge of the social organization of the pre‐Columbian communities. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 06, 2014   doi: 10.1002/ajpa.22524   open full text
• Questions of khoesan continuity: Dental affinities among the indigenous holocene peoples of South Africa.
  Joel D. Irish.
  American Journal of Physical Anthropology. May 02, 2014
  The present report follows up on the findings of previous research, including recent bioarchaeological study of well‐dated Khoesan skeletal remains, that posits long term biological continuity among the indigenous peoples of South Africa after the Pleistocene. The Arizona State University Dental Anthropology System was employed to record key crown, root, and intraoral osseous nonmetric traits in six early‐through‐late Holocene samples from the Cape coasts. Based on these data, phenetic affinities and an identification of traits most important in driving intersample variation were determined using principal components analysis and the mean measure of divergence distance statistic. To expand biological affinity comparisons into more recent times, and thus preliminarily assess the dental impact of disproportionate non‐Khoesan gene flow into local peoples, dental data from historic Khoekhoe and San were also included. Results from the prehistoric comparisons are supportive of population continuity, though a sample from Matjes River Rockshelter exhibits significant, albeit slight, phenetic distance from other early samples. This and some insignificant regional divergence among these coastal samples may be related to environmental and cultural factors that drove low‐level reproductive isolation. Finally, a close affinity of historic San to all samples, and a significant difference of Khoekhoe from most early samples is reflective of documented population history following immigration of Bantu‐speakers and, later, Europeans into South Africa. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  May 02, 2014   doi: 10.1002/ajpa.22526   open full text
• A morphological intermediate between eosimiiform and simiiform primates from the late middle Eocene of Tunisia: Macroevolutionary and paleobiogeographic implications of early anthropoids.
  Laurent Marivaux, El Mabrouk Essid, Wissem Marzougui, Hayet Khayati Ammar, Sylvain Adnet, Bernard Marandat, Gilles Merzeraud, Anusha Ramdarshan, Rodolphe Tabuce, Monique Vianey‐Liaud, Johan Yans.
  American Journal of Physical Anthropology. April 30, 2014
  Although advanced anthropoid primates (i.e., Simiiformes) are recorded at the end of the Eocene in North Africa (Proteopithecidae, Parapithecidae, and Oligopithecidae), the origin and emergence of this group has so far remained undocumented. The question as to whether these primates are the result of a monophyletic radiation of endemic anthropoids in Africa, or several Asian clades colonizing Africa, is a current focus of paleoprimatology. In this article, we report the discovery of a new anthropoid from Djebel el Kébar in central Tunisia, dating from the late middle Eocene (Bartonian). This taxon, Amamria tunisiensis, new genus and species, currently known by only one isolated upper molar, is among the most ancient anthropoids to be recorded in Africa thus far. Amamria displays a suite of dental features that are primarily observed in Eosimiiformes (stem Anthropoidea). However, it is not allocated to any known family of that group (i.e., Asian Eosimiidae and Afro‐Asian Afrotarsiidae) inasmuch as it develops some dental traits that are unknown among eosimiiforms, but can be found in African simiiform anthropoids such as proteopithecids and oligopithecids. With such a mosaic of dental traits, Amamria appears to be a structural intermediate, and as such it could occupy a key position, close to the root of the African simiiforms. Given its antiquity and its apparent pivotal position, the possibility exists that Amamria could have evolved in Africa from Asian eosimiiform or Asian “proto”‐simiiform ancestors, which would have entered Africa sometime during the middle Eocene. Amamria could then represent one of the earliest offshoots of the African simiiform radiation. This view would then be rather in favor of the hypothesis of a monophyletic radiation of endemic simiiform anthropoids in Africa. Finally, these new data suggest that there must have been at least two Asian anthropoid colonizers of Africa: the afrotarsiids and the ancestor of Amamria. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  April 30, 2014   doi: 10.1002/ajpa.22523   open full text
• Using multivariate adaptive regression splines to estimate subadult age from diaphyseal dimensions.
  Kyra E. Stull, Ericka N. L'Abbé, Stephen D. Ousley.
  American Journal of Physical Anthropology. April 30, 2014
  Subadult age estimation is considered the most accurate parameter estimated in a subadult biological profile, even though the methods are deficient and the samples from which they are based are inappropriate. The current study addresses the problems that plague subadult age estimation and creates age estimation models from diaphyseal dimensions of modern children. The sample included 1,310 males and females between the ages of birth and 12 years. Eighteen diaphyseal length and breadth measurements were obtained from Lodox Statscan radiographic images generated at two institutions in Cape Town, South Africa, between 2007 and 2012. Univariate and multivariate age estimation models were created using multivariate adaptive regression splines. k‐fold cross‐validated 95% prediction intervals (PIs) were created for each model, and the precision of each model was assessed. The diaphyseal length models generated the narrowest PIs (2 months to 6 years) for all univariate models. The majority of multivariate models had PIs that ranged from 3 months to 5 and 6 years. Mean bias approximated 0 for each model, but most models lost precision after 10 years of age. Univariate diaphyseal length models are recommended for younger children, whereas multivariate models are recommended for older children where the inclusion of more variables minimized the size of the PIs. If diaphyseal lengths are not available, multivariate breadth models are recommended. The present study provides applicable age estimation formulae and explores the advantages and disadvantages of different subadult age estimation models using diaphyseal dimensions. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  April 30, 2014   doi: 10.1002/ajpa.22522   open full text
• Health in post‐black death London (1350–1538): Age patterns of periosteal new bone formation in a post‐epidemic population.
  Sharon N. DeWitte.
  American Journal of Physical Anthropology. April 17, 2014
  Previous research has shown that the Black Death targeted older adults and individuals who had been previously exposed to physiological stressors. This project investigates whether this selectivity of the Black Death, combined with post‐epidemic rising standards of living, led to significant improvements in patterns of skeletal stress markers, and by inference in health, among survivors and their descendants. Patterns of periosteal lesions (which have been previously shown, using hazard analysis, to be associated with elevated risks of mortality in medieval London) are compared between samples from pre‐Black Death (c. 1,000–1,300, n = 464) and post‐Black Death (c. 1,350–1,538, n = 133) London cemeteries. To avoid the assumptions that stress markers alone provide a direct measure of health and that a change in frequencies of the stress marker by itself indicates changes in health, this study assesses age‐patterns of the stress marker to obtain a more nuanced understanding of the population‐level effects of an epidemic disease. Age‐at‐death in these samples is estimated using transition analysis, which provides point estimates of age even for the oldest adults in these samples and thus allows for an examination of physiological stress across the lifespan. The frequency of lesions is significantly higher in the post‐Black Death sample, which, at face value, might indicate a general decline in health. However, a significant positive association between age and periosteal lesions, as well as a significantly higher number of older adults in the post‐Black Death sample more likely suggests improvements in health following the epidemic. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  April 17, 2014   doi: 10.1002/ajpa.22510   open full text
• Examining short‐term nutritional status among BaAka foragers in transitional economies.
  Melissa J. Remis, Carolyn A. Jost Robinson.
  American Journal of Physical Anthropology. April 17, 2014
  Foragers in transitioning economies are at an increased risk of negative health outcomes as they undergo changes in subsistence patterns and diet. Here, we provide anthropometric data and examine the nutrition and health of adult BaAka foragers in relationship to declining wildlife and economic change in the Dzanga Sangha Protected Areas (APDS), Central African Republic. From June to August 2012, we collected biological data and dietary recall surveys from individuals in Mossapoula (MS) and Yandoumbé (YDBE) villages using standard anthropometric techniques and a single capillary blood finger prick. In our analysis, we identified variation in anthropometric measurements and hemoglobin levels by village (MS = 66, YDBE = 75) and gender (64 men, 77 women). Immigration, increased gun hunting and wildlife trades have reduced forager reliance on forest resources. These changes are evidenced in the marginal health of contemporary BaAka foragers of APDS. Although anthropometric measures of nutritional status do not significantly differ between communities, hemoglobin data highlight inequities in access to forest products between villages with different proximity to community hunting zones. Further, poor dietary diversity and low frequency of purchased foods in the diet indicate that the transition to a market economy has not been fully realized and diets are impoverished. Economic changes appear to have had the most impact at MS village, where forest use is most restricted and consumption of meat and forest products was reduced. This work highlights the nutritional and health needs of foragers in rapidly transitioning economies; especially those impacted by conservation management and zoning policies. Am J Phys Anthropol, 2014. © 2014 Wiley Periodicals, Inc.

  April 17, 2014   doi: 10.1002/ajpa.22521   open full text
• The meaning of weaning in wild Phayre's leaf monkeys: Last nipple contact, survival, and independence.
  Carola Borries, Amy Lu, Kerry Ossi‐Lupo, Eileen Larney, Andreas Koenig.
  American Journal of Physical Anthropology. March 11, 2014
  In primates and other mammals, weaning is an equivocal concept, as is reflected in the numerous ways it is measured: a) first intake of solid food, b) conflict over access to the nipple, c) ability to survive without mother, d) maternal resumption of cycling, or e) the cessation of nipple contact. The lack of a consistent definition means that weaning age, although it falls between gestation (fetal growth) and age at first reproduction (most energy diverted from growth), is currently not a reliable life history variable capturing offspring independence. Using data for wild Phayre's leaf monkeys (Trachypithecus phayrei crepusculus) at Phu Khieo Wildlife Sanctuary, Thailand (51 offspring, four groups), we asked whether the end of nipple contact indicates offspring independence as measured by survival to 3 years. To establish a baseline for the onset of independence, we assessed the youngest age at which individuals were orphaned (15–17 months) but then survived to 3 years. Next we determined that offspring age at last nipple contact (19.0 months) was comparable to two other independently calculated measures: offspring age at mother's first postpartum ovulation (11.5 months), and age at mother's re‐conception (15.6 months). Using these separate “starting points,” we arrived at similar ages for nipple contact cessation (18.4 and 19.2 months, respectively). Overall, in wild (but not in provisioned) Asian colobines, age at last nipple contact was allometrically related to adult female body mass, supporting its designation as a life history variable. Future comparisons need to show if this holds for other taxa. Am J Phys Anthropol 154:291–301, 2014. © 2014 Wiley Periodicals, Inc.

  March 11, 2014   doi: 10.1002/ajpa.22511   open full text
• Sexual dimorphism in human cranial trait scores: Effects of population, age, and body size.
  Heather M. Garvin, Sabrina B. Sholts, Laurel A. Mosca.
  American Journal of Physical Anthropology. March 04, 2014
  Sex estimation from the skull is commonly performed by physical and forensic anthropologists using a five‐trait scoring system developed by Walker. Despite the popularity of this method, validation studies evaluating its accuracy across a variety of samples are lacking. Furthermore, it remains unclear what other intrinsic or extrinsic variables are related to the expression of these traits. In this study, cranial trait scores and postcranial measurements were collected from four diverse population groups (U.S. Whites, U.S. Blacks, medieval Nubians, and Arikara Native Americans) following Walker's protocols (total n = 499). Univariate and multivariate analyses were utilized to evaluate the accuracy of these traits in sex estimation, and to test for the effects of population, age, and body size on trait expressions. Results revealed significant effects of population on all trait scores. Sample‐specific correct sex classification rates ranged from 74% to 94%, with an overall accuracy of 85% for the pooled sample. Classification performance varied among the traits (best for glabella and mastoid scores and worst for nuchal scores). Furthermore, correlations between traits were weak or nonsignificant, suggesting that different factors may influence individual traits. Some traits displayed correlations with age and/or postcranial size that were significant but weak, and within‐population analyses did not reveal any consistent relationships between these traits across all groups. These results indicate that neither age nor body size plays a large role in trait expression, and thus does not need to be incorporated into sex estimation methods. Am J Phys Anthropol 154:259–269, 2014. © 2014 Wiley Periodicals, Inc.

  March 04, 2014   doi: 10.1002/ajpa.22502   open full text
• Bioarchaeology of the middle Neolithic: Evidence for archery among early european farmers.
  Aline Thomas.
  American Journal of Physical Anthropology. March 04, 2014
  This article focuses on Neolithic skeletons associated with the first monumental cemeteries of Western Europe and specifically those of the Cerny culture (Paris Basin, France). While this cultural context is an agrarian one, numerous arrowheads derived from complete hunting equipment are present in numerous graves. The goal of this work is to evaluate the morphological and pathological differences among the individuals according to the presence of arrowheads in their graves. It is postulated that those buried with such artifacts practiced archery, unlike their counterparts. Only adult males were selected for study to limit the effect of non‐mechanical factors such as age‐ and sex‐related modifications. The corpus consists of 36 males reliably identified among the 101 Cerny adults currently available. Thirteen men are associated with arrowheads. Variations in morphology and robusticity are evaluated on the basis of the external geometric properties of the appendicular skeleton. Entheseal changes to fibrocartilaginous attachment sites of upper and lower limbs are also examined. Both nonpathological skeletal adaptations and pathological indicators are consistent and reveal significant differences between the two groups compared. Functional adaptation is observed in the forearm bones and the clavicle in response to mechanical loads, and enthesopathies suggest repeated forceful use of upper limb muscles. These osteological changes specifically reflect the higher intensity upper limb activity of the men buried with arrowheads and correspond with the medical data on known archers, suggesting that this specific forceful task is linked to the practice of archery. Am J Phys Anthropol 154:279–290, 2014. © 2014 Wiley Periodicals, Inc.

  March 04, 2014   doi: 10.1002/ajpa.22504   open full text
• Aggregation, interregional interaction, and postmarital residence patterning: A study of biological variation in the late prehistoric middle Ohio Valley.
  Robert A. Cook, B. Scott Aubry.
  American Journal of Physical Anthropology. March 04, 2014
  This study examines a perennial problem in anthropology, changes in postmarital residence patterning. Cross‐cultural patterns related to shifts from patrilocal to matrilocal patterns have been attributed to changes in subsistence and/or the result of migrants entering a populated region. Shifts from matrilocal to multilocal patterns have been found to be related to depopulation. This study examines these possibilities in an archeological context through morphometric analyses of human dentition. Comparisons in variability among males and females are made at four Fort Ancient sites in the Middle Ohio Valley that date to sequential time periods between circa A.D. 1000 and 1650. Results show that the earliest site (Turpin) that was occupied during the transition to maize agriculture was patrilocal, whereas two subsequent sites (Anderson and SunWatch) that were occupied after the transition to a maize‐focused diet reflect a matrilocal pattern. The most recently occupied site (Madisonville), occupied during a time of depopulation of the region after a decline in levels of maize consumption and a marked population shuffling contains a multilocal pattern. These results fit well with the various cross‐cultural findings regarding shifts in postmarital residence patterns. Am J Phys Anthropol 154:270–278, 2014. © 2014 Wiley Periodicals, Inc.

  March 04, 2014   doi: 10.1002/ajpa.22503   open full text
• Estimating striae of Retzius periodicity nondestructively using partial counts of perikymata.
  Gina McFarlane, Judith Littleton, Bruce Floyd.
  American Journal of Physical Anthropology. February 28, 2014
  Accurate age estimations for enamel formation and the timing of enamel hypoplasia have traditionally only been available through histological analyses of dental thin sections, which is a difficult and destructive process. However, an association between striae of Retzius periodicity, crucial for accurate aging, and the total number of striae in imbricational enamel has been reported in the literature. This means periodicity can be estimated nondestructively but is reliant on all perikymata being visible along the crown surface. Therefore, crowns with worn or damaged surfaces may not be able to be assessed, potentially limiting sample sizes. We tested this relationship in a modern New Zealand sample and investigated whether reliable associations might be identified using only partial perikymata counts from the cervical half of the crown. Using mandibular canines (n = 11), the distribution of perikymata per decile was recorded using high definition replica surfaces. Thin sections of the same crowns were used to assess periodicity histologically along with striae of Retzius distributions. A strong correlation between total striae numbers and periodicity was also identified in our sample. Furthermore, we report strong correlations that allow periodicity to be estimated from perikymata counts using only 10% of crown height when certain deciles are used. Based on these findings, we propose a simple matrix that can be developed for nondestructively estimating periodicity based on the range of perikymata counts in the sixth to ninth deciles. Am J Phys Anthropol 154:251–258, 2014. © 2014 Wiley Periodicals, Inc.

  February 28, 2014   doi: 10.1002/ajpa.22501   open full text
• Estimating fossil hominin body mass from cranial variables: An assessment using CT data from modern humans of known body mass.
  Marina Elliott, Helen Kurki, Darlene A. Weston, Mark Collard.
  American Journal of Physical Anthropology. February 26, 2014
  Body mass estimates are integral to a wide range of inferences in paleoanthropology. Most techniques employ postcranial elements, but predictive equations based on cranial variables have also been developed. Three studies currently provide regression equations for estimating mass from cranial variables, but none of the equations has been tested on samples of known mass. Nor have the equations been compared to each other in terms of performance. Consequently, this study assessed the performance of existing cranial equations using computed tomography scans from a large, documented sample of modern humans of known body mass. Virtual models of the skull were reconstructed and measured using computer software, and the resulting variables were entered into three sets of published regression equations. Estimated and known body masses were then compared. For most equations, prediction errors were high and few individuals were estimated within ±20% of their known mass. Only one equation satisfied the accuracy criteria. In addition, variables that had been previously argued to be good predictors of mass in hominins, including humans, did not estimate mass reliably. These results have important implications for paleoanthropology. In particular, they emphasize the need to develop new equations for estimating fossil hominin body mass from cranial variables. Am J Phys Anthropol 154:201–214, 2014. © 2014 Wiley Periodicals, Inc.

  February 26, 2014   doi: 10.1002/ajpa.22493   open full text
• Health Is not always written in bone: Using a modern comorbidity index to assess disease load in paleopathology.
  Katherine Schaik, Dmitry Vinichenko, Frank Rühli.
  American Journal of Physical Anthropology. February 21, 2014
  Paleopathology has revealed much about disease in the past but is usually limited to conditions with osteological manifestations; this often excludes acute soft tissue infections and causes of death for most individuals in the past and present. Our understanding of the evolution of disease is essential for contextualizing and predicting the epidemiological shifts that are happening in modern society, as high rates of infectious disease coexist alongside high rates of chronic disease in rates unlike those observed previously in human history. Moreover, many physiological states not previously classified as “disease” (obesity) have become pathologized, influencing our conception of disease and what defines health. By using the Galler Collection, a pre‐antibiotic and pre‐chemotherapeutic osteological series with modern autopsy records, our research quantifies disease burden of the past using the Charlson Index (CI), a modern comorbidity index of disease severity. Galler Collection remains and autopsy records were scored with the Charlson Index to correlate bone findings with soft tissue findings, and statistical analysis was performed for cumulative scores and absolute diagnosis counts, with patients stratified by sex and cause of death (pneumonia or cancer). Osteological diagnosis counts were more predictive of soft‐tissue autopsy disease counts than were associated cumulative CI scores. Diagnosis counts and CI scores for osteological data were more closely related to associated soft tissue data for cancer patients than for pneumonia patients. This research indicates how interdisciplinary paleopathological analysis assists in making more reliable assessments of health and mortality in the past, with implications for trending and predicting future epidemiological shifts. Am J Phys Anthropol 154:215–221, 2014. © 2014 Wiley Periodicals, Inc.

  February 21, 2014   doi: 10.1002/ajpa.22494   open full text
• Developing a pig model for crypt fenestration‐induced localized hypoplastic enamel defects in humans.
  Mark F. Skinner, Antonia T. Rodrigues, Chris Byra.
  American Journal of Physical Anthropology. February 21, 2014
  Hypoplastic pits on human deciduous canine teeth are attributed to nutritionally induced thinning of the crypt wall prior to eruption, exposing ameloblasts to unspecified physical trauma through the fenestration. Traditionally known as localized hypoplasia of the primary canine (LHPC), this little‐understood condition is reported in fields ranging from public health to bioarchaeology. We propose the defect be termed a ‘crypt fenestration hypoplastic enamel defect’ (CFED) to reflect that an analogous lesion is created postnatally on maxillary molars of pigs. Pigs are accepted as a suitable proxy for many studies in human biology. We compare fenestration defects and CFEDs between 50 Sick Pen pigs, who died naturally, and 20 Controls. Observations were made of the presence, number and size of fenestrations in molar crypts. CFEDs were counted on erupted deciduous last molars and permanent first molars. Signs of being underweight and cranio‐dental infection at death were recorded. Sick pen pigs show significantly more fenestrations at death and CFEDs acquired before death. These conditions co‐occur with infection and poor growth. The deep fibers of temporalis muscle lie adjacent to the crypt wall of maxillary molars. We propose that contraction of this muscle during suckling and chewing creates large compressive forces against fenestrated bony surfaces sufficient to have physiological consequences for physically unprotected ameloblasts. While we conclude that a pig model is appropriate to study fenestration‐induced enamel defects, this naturalistic experiment leaves unresolved whether osteopenia in pigs, and by extension in human infants, is due to disease and/or malnutrition. Am J Phys Anthropol 154:239–250, 2014. © 2014 Wiley Periodicals, Inc.

  February 21, 2014   doi: 10.1002/ajpa.22497   open full text
• Population level differences in adult body mass emerge in infancy and early childhood: Evidence from a global sample of low and lower‐income countries.
  Craig Hadley, Daniel J. Hruschka.
  American Journal of Physical Anthropology. February 19, 2014
  Many studies have linked measures of adult body shape and mass in ancient and contemporary populations to ecogeographical variables such as temperature and latitude. These results tend to support Bergmann's rule, which posits that bodies will be relatively less slender for their height in colder climates and more slender in warmer climates. Less well explored is the ontogeny of these population‐level differences. Here we use data on infants and children from 46 low and lower income countries to test whether children's weight for height is associated with measures of temperature and latitude. We also test the hypothesis that children living in areas with greater pathogen prevalence will be lighter for their height because of life history trade‐offs between investment in immune function and growth. Finally, we test whether population specific adult body mass predicts infant and child body mass, and whether this is independent of ecogeographical variables. Our results show that maximum monthly temperature explains 17% of children's weight for height while adult population‐level body mass explains ∼44% (Table ). The measures of pathogen prevalence explain little of the variation in children's body shape (8%; P > 0.05). Our results suggest that population differences are consistent with Bergmann's rule but parental body shape explains more variance. Moreover, these population‐level differences arise early in development, suggesting that any possible environmental influences occur in utero and/or result from epigenetic or population genetic differences. Am J Phys Anthropol 154:232–238, 2014. © 2014 Wiley Periodicals, Inc.

  February 19, 2014   doi: 10.1002/ajpa.22496   open full text
• Mortality, fertility, and the OY ratio in a model hunter–gatherer system.
  Andrew A. White.
  American Journal of Physical Anthropology. February 13, 2014
  An agent‐based model (ABM) is used to explore how the ratio of old to young adults (the OY ratio) in a sample of dead individuals is related to aspects of mortality, fertility, and longevity experienced by the living population from which the sample was drawn. The ABM features representations of rules, behaviors, and constraints that affect person‐ and household‐level decisions about marriage, reproduction, and infant mortality in hunter–gatherer systems. The demographic characteristics of the larger model system emerge through human‐level interactions playing out in the context of “global” parameters that can be adjusted to produce a range of mortality and fertility conditions. Model data show a relationship between the OY ratios of living populations (the living OY ratio) and assemblages of dead individuals drawn from those populations (the dead OY ratio) that is consistent with that from empirically known ethnographic hunter–gatherer cases. The dead OY ratio is clearly related to the mean ages, mean adult mortality rates, and mean total fertility rates experienced by living populations in the model. Sample size exerts a strong effect on the accuracy with which the calculated dead OY ratio reflects the actual dead OY ratio of the complete assemblage. These results demonstrate that the dead OY ratio is a potentially useful metric for paleodemographic analysis of changes in mortality and mean age, and suggest that, in general, hunter–gatherer populations with higher mortality, higher fertility, and lower mean ages are characterized by lower dead OY ratios. Am J Phys Anthropol 154:222–231, 2014. © 2014 Wiley Periodicals, Inc.

  February 13, 2014   doi: 10.1002/ajpa.22495   open full text
• Genetic influences on the development of grip strength in adolescence.
  Joshua Isen, Matt McGue, William Iacono.
  American Journal of Physical Anthropology. February 12, 2014
  Enhanced physical strength is a secondary sex characteristic in males. Sexual dimorphism in physical strength far exceeds sex differences in stature or total body mass, suggesting a legacy of intense sexual selection. Upper‐body strength is a particularly promising marker of intrasexual competitiveness in young men. Consequently, it is assumed that sex‐influenced gene expression contributes to the development of physical strength. It is unclear, however, whether the underlying sources of individual differences in strength development are comparable across sex. We obtained three measurements of hand‐grip strength (HGS) over a six‐year period spanning adolescence in male and female same‐sex twins (N = 2,513). Biometrical latent growth models were used to partition the HGS variance at age 11 (intercept) and its growth over time (slope) into genetic and environmental components. Results demonstrated that variance around the intercept was highly heritable in both males and females (88% and 79%, respectively). In males, variance around the slope exceeded that of the intercept, while the reverse held for females. Additive genetic effects accounted for most (80%) of the variance around the slope in males, but were of less importance in females (heritability = 28%). Absolute genetic variance around the slope was nearly nine‐fold higher in males. This striking disparity suggests that the developmental processes shaping HGS growth are different between the sexes. We propose that this might account for the sex‐specific pattern of associations between HGS and external measures (e.g., digit ratio and physical aggression) typically reported in the literature. Our results underscore the role of endogenous androgenic influences in the development of physical strength. Am J Phys Anthropol 154:189–200, 2014. © 2014 Wiley Periodicals, Inc.

  February 12, 2014   doi: 10.1002/ajpa.22492   open full text
• Biocultural implications of oral pathology in an ancient Central California population.
  Mark C. Griffin.
  American Journal of Physical Anthropology. February 12, 2014
  Bioarchaeologists have long noted two unusual trends in the dentitions of prehistoric Native Californian populations: high rates of wear and low prevalence of caries. The Central California site of CA‐CCO‐548 offers a unique opportunity to examine the relationship between oral pathology and extreme dental wear in a large (n = 480), ancient (4,300–3,100 BP), and temporally well‐defined population sample. This study specifically examines three interrelated processes of the oral cavity in this population: dental wear, dental caries, and periodontal disease. The results show high levels of dental wear (average of 6.1, Smith system), low frequencies of carious lesions (2.5%), low frequencies of periodontal disease (17.8%), and high frequencies of periapical abscesses (10.7%). The pathological processes examined here have complicated multifactorial etiologies. However, they all share the common primary etiological agents of facultative pathogenic bacteria proliferation in the oral biofilm. Integration of the current etiological explanations for infections of the oral cavity, information from the ethnographic record pertaining to subsistence and activity patterns in Native Californian populations, and statistical analysis of specific disease and wear patterns leads to a novel explanation for the observed pattern of oral pathology in this population sample. Specifically, the introduction of antibacterial compounds through dietary items and non‐alimentary tooth use is suggested as the most likely explanation for the unusually low prevalence of dental caries and periodontal disease. Am J Phys Anthropol 154:171–188, 2014. © 2014 Wiley Periodicals, Inc.

  February 12, 2014   doi: 10.1002/ajpa.22491   open full text
• Human dietary δ15N intake: Representative data for principle food items.
  F. Huelsemann, K. Koehler, H. Braun, W. Schaenzer, U. Flenker.
  American Journal of Physical Anthropology. August 06, 2013
  Dietary analysis using δ15N values of human remains such as bone and hair is usually based on general principles and limited data sets. Even for modern humans, the direct ascertainment of dietary δ15N is difficult and laborious, due to the complexity of metabolism and nitrogen fractionation, differing dietary habits and variation of δ15N values of food items. The objective of this study was to summarize contemporary regional experimental and global literature data to ascertain mean representative δ15N values for distinct food categories. A comprehensive data set of more than 12,000 analyzed food samples was summarized from the literature. Data originated from studies dealing with (1) authenticity tracing or origin control of food items, and (2) effects of fertilization or nutrition on δ15N values of plants or animals. Regional German food δ15N values revealed no major differences compared with the mean global values derived from the literature. We found that, in contrast to other food categories, historical faunal remains of pig and poultry are significantly enriched in 15N compared to modern samples. This difference may be due to modern industrialized breeding practices. In some food categories variations in agricultural and feeding regimens cause significant differences in δ15N values that may lead to misinterpretations when only limited information is available. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  August 06, 2013   doi: 10.1002/ajpa.22328   open full text
• Male philopatry in spider monkeys revisited.
  Filippo Aureli, Anthony Di Fiore, Evin Murillo‐Chacon, Shoji Kawamura, Colleen M. Schaffner.
  American Journal of Physical Anthropology. August 01, 2013
  Dispersal patterns are critical for understanding social systems as they influence social interactions and relationships. Spider monkeys (Ateles spp.) are typically described as being characterized by male philopatry and female dispersal, with these patterns reflected in stronger affiliative and cooperative relationships among males than among females. Recent findings, however, indicate that male–male relationships may not be as uniformly strong as previously thought, which suggests that male philopatry in spider monkeys may not be universal. Here, we report the first confirmed cases of male immigration and group takeover in spider monkeys. Data were collected on one community of Ateles geoffroyi in northwestern Costa Rica. Behavioral and demographic data were recorded during subgroup follows across 6.5 years, and fecal samples of community members were collected for genetic analysis of relatedness. We documented two separate cases of immigration involving multiple males, which resulted in take‐over of the study community by extra‐community males and the concomitant disappearance of the resident males. In the study community, males were no more closely related to one another, on average, than females were, contrary to what would be expected if males were the more philopatric sex. Comparison of corrected assignment indices for males and females also revealed no evidence of sex‐biased dispersal. Our findings suggest that in spider monkeys male immigration may occur under certain demographic circumstances, contributing to a view of greater flexibility in their social system than previously appreciated. This discovery has implications for other species that are typically characterized by male philopatry. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  August 01, 2013   doi: 10.1002/ajpa.22331   open full text
• Prevalence and patterning of maxillary premolar accessory ridges (MxPARs) in several human populations.
  Suzanna Mihailidis, Graham Scriven, Mohd Khamis, Grant Townsend.
  American Journal of Physical Anthropology. August 01, 2013
  We present new data on the prevalence and patterning of the maxillary premolar accessory ridge (MxPAR), a common but understudied morphological dental trait that is expressed as a linear elevation extending from the buccal cusp ridge to the medial sulcus of maxillary premolar teeth. A total of 579 sets of dental casts, representing six ethnic groups, were scored using the five‐grade system proposed by Burnett et al. (2010). The frequency and distribution of the MxPAR were determined by tooth type, sex, side, locus and ethnicity, and the applicability of the scoring system was assessed. The MxPAR was found in approximately two‐thirds of premolar teeth, more often on second than first premolars, and more often on the distal aspect of the occlusal surface than the mesial. There was some evidence that more pronounced forms of the feature occurred more often in males than females, and that there may be some directionality in its expression between sides. Variation was also noted in the frequency of occurrence and degree of expression of the MxPAR between ethnic groups. Intra‐ and inter‐observer concordance rates for scoring the MxPAR were low, confirming that it was difficult to score the trait identically on two different occasions. Our findings have clarified the distribution of the MxPAR within the dentition and between ethnic groups, and highlighted the need for researchers to carry out thorough replicability studies and to decide on an appropriate breakpoint for determining presence or absence of this feature before embarking on genetic studies or bio‐distance analyses. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  August 01, 2013   doi: 10.1002/ajpa.22323   open full text
• Variability in the developmental life history of the genus gorilla.
  Tara S. Stoinski, Bonnie Perdue, Thomas Breuer, Michael P. Hoff.
  American Journal of Physical Anthropology. August 01, 2013
  Life history is influenced by factors both intrinsic (e.g., body and relative brain size) and extrinsic (e.g., diet, environmental instability) to organisms. In this study, we examine the prediction that energetic risk influences the life history of gorillas. Recent comparisons suggest that the more frugivorous western lowland gorilla shows increased infant dependence, and thus a slower life history, than the primarily folivorous mountain gorilla to buffer against the risk of starvation during periods of food unpredictability. We further tested this hypothesis by incorporating additional life history data from wild western lowland gorillas and captive western lowland gorillas with the assumption that the latter live under ecological conditions of energetic risk that more closely resemble those of mountain gorillas and thus should show faster life histories than wild members of the species. Overall, we found captive western lowland and wild mountain gorillas to have faster developmental life histories than wild western lowland gorillas, weaning their infants approximately a year earlier and thus reducing interbirth intervals by a year. These results provide support that energetic risk plays an important role in substantially determining gorilla life history. Unlike previous assertions, gorillas do not have faster life histories, at least at the genus level, than other great apes. This calls for a re‐evaluation of theories concerning comparative ape life history and evolution and highlights the need for data from additional populations that vary in energetic risk. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  August 01, 2013   doi: 10.1002/ajpa.22301   open full text
• Dental wear and cultural behavior in Middle Paleolithic humans from the Near East.
  Luca Fiorenza, Ottmar Kullmer.
  American Journal of Physical Anthropology. August 01, 2013
  Neanderthals and anatomically modern humans (AMHs) may have lived in close proximity in the Near East region during Middle Paleolithic times. Although functional morphological analyses suggest a marked behavioral contrast between these two human groups, new dental micro‐ and macro‐wear studies, together with new archaeological data, have revealed some similarities in ecology and dietary habits. In this study, we analyze the tooth wear patterns of Neanderthals and AMH from Middle Paleolithic sites of Israel and Northern Iraq, using the Occlusal Fingerprint Analysis (OFA) method to virtually reconstruct the jaw movements responsible for the creation of the occlusal wear areas. We particularly focus on para‐facets, a distinctive type of wear which has been previously described in the dentition of historic and modern hunter‐gatherers. The analysis reveals a similarity in para‐facet frequency between early Near Eastern Neanderthals and AMH, and a significant difference with other Pleistocene human groups. The absence of antagonist occlusal contacts in the lower teeth and the occlusal compass analysis suggest that para‐facet formation is not related to normal mastication but to nonmasticatory activities. Thus, the identification of these nonmasticatory wear areas on the molars of early Near Eastern Neanderthals and AMH may indicate analogous tooth‐tool uses for daily task activities. These may have emerged independently or could be interpreted as indirect evidence of cultural interactions between these two groups. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  August 01, 2013   doi: 10.1002/ajpa.22335   open full text
• The Cost of defeat: Capuchin groups travel further, faster and later after losing conflicts with neighbors.
  Margaret C. Crofoot.
  American Journal of Physical Anthropology. July 31, 2013
  Although competition between social groups is central to hypotheses about the evolution of human social organization, competitive interactions among group‐mates are thought to play a more dominant role in shaping the behavior and ecology of other primate species. However, few studies have directly tested the impact of intergroup conflicts in non‐human primates. What is the cost of defeat? To address this question, the movements of six neighboring white‐faced capuchin (Cebus capucinus) social groups living on Barro Colorado Island, Panama were tracked simultaneously using an Automated Radio Telemetry System (ARTS), for a period of six months. Groups moved 13% (441 m) further on days they lost interactions compared with days they won interactions. To cover these larger distances, they traveled faster, stopped less frequently, and remained active later in the evening. Defeat also caused groups to alter their patterns of space use. Losing groups had straighter travel paths than winning groups, larger net displacements and were more likely to change their sleeping site. These results demonstrate that losing groups pay increased travel costs and suggest that they forage in low‐quality areas. They provide some of the first direct evidence that intergroup conflicts have important energetic consequences for members of competitively unsuccessful primate social groups. A better understanding of how intergroup competition impacts patterns of individual fitness is thus needed to clarify the role that this group‐level process plays in shaping the evolution of human‐ and non‐human primate behavior. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 31, 2013   doi: 10.1002/ajpa.22330   open full text
• Mitochondrial diversity in human head louse populations across the Americas.
  Marina S. Ascunce, Jackie Fane, Gebreyes Kassu, Ariel C. Toloza, Maria I. Picollo, Angélica González‐Oliver, David L. Reed.
  American Journal of Physical Anthropology. July 30, 2013
  Anthropological studies suggest that the genetic makeup of human populations in the Americas is the result of diverse processes including the initial colonization of the continent by the first people plus post‐1492 European migrations. Because of the recent nature of some of these events, understanding the geographical origin of American human diversity is challenging. However, human parasites have faster evolutionary rates and larger population sizes allowing them to maintain greater levels of genetic diversity than their hosts. Thus, we can use human parasites to provide insights into some aspects of human evolution that may be unclear from direct evidence. In this study, we analyzed mitochondrial DNA (mtDNA) sequences from 450 head lice in the Americas. Haplotypes clustered into two well‐supported haplogroups, known as A and B. Haplogroup frequencies differ significantly among North, Central and South America. Within each haplogroup, we found evidence of demographic expansions around 16,000 and 20,000 years ago, which correspond broadly with those estimated for Native Americans. The parallel timing of demographic expansions of human lice and Native Americans plus the contrasting pattern between the distribution of haplogroups A and B through the Americas suggests that human lice can provide additional evidence about the human colonization of the New World. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22336   open full text
• Altitude effects on growth of indigenous children in Oaxaca, Southern Mexico.
  Bertis B. Little, Robert M. Malina, Maria Eugenia Pena Reyes, Guillermo Bali Chavez.
  American Journal of Physical Anthropology. July 30, 2013
  The effect of altitude of residence on the growth status of 11,454 indigenous school children 6–14 years of age in Oaxaca, southern Mexico, was examined. Indicators of living conditions (human development index [HDI], index of community nutritional risk [INR], index of marginalization [IM], index of relative isolation [II]) were regressed on z‐scores for height, weight and BMI, and the residuals were regressed on altitude of residence (km). Independent of other environmental conditions, altitude negatively affected height by approximately −0.07 z‐scores per kilometer altitude above sea level. The estimated average decrease in stature was 0.92 cm per kilometer elevation. BMI was significantly increased, 1.2 units per kilometer elevation, consistent with earlier studies of growth status and altitude. In contrast, weight was not affected by altitude of residence. Approximately 36% of the reduction in height and 54% of the increase in BMI were due to altitude effects; the remaining changes in height and BMI were associated with environmental factors reflected in the indices of community well‐being considered. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22326   open full text
• Manual pressure distribution patterns of knuckle‐walking apes.
  Stacey Matarazzo.
  American Journal of Physical Anthropology. July 30, 2013
  Differences in how the hands of gorillas and chimpanzees contact the ground while knuckle walking have been noted but generally not quantified. It is widely believed that gorillas maintain a pronated arm and contact the ground with digits 2–5 consistently, while chimpanzees have variable arm position and digit contact. To further test these generalizations, distribution of pressure across the manus, peak digital pressures, and hand position were quantified using a pressure mat in eight captive chimpanzees (Pan troglodytes) and seven gorillas (Gorilla gorilla). Chimpanzees and gorillas make initial ground contact with the ulnar aspect of the hand and pressure moves radially. They differ in which digit usually makes final contact and receives maximum pressure, and hand position during contact. Gorillas regularly use a palm‐back hand position and touch‐off with digit 2. They show less variation in pressure application across the digits. Chimpanzees are more variable in hand position and pressure application. In both, hand position plays a key role in determining which digit acts as the final touch‐off element. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22325   open full text
• Application of the anatomical method to estimate the maximum adult stature and the age‐at‐death stature.
  Markku Niskanen, Heli Maijanen, Donna McCarthy, Juho‐Antti Junno.
  American Journal of Physical Anthropology. July 30, 2013
  This study focuses on the age adjustment of statures estimated with the anatomical method. The research material includes 127 individuals from the Terry Collection. The cadaveric stature (CSTA)–skeletal height (SKH) ratios indicate that stature loss with age commences before SKH reduction. Testing three equations to estimate CSTA at the age at death and CSTA corrected to maximum stature from SKH indicates that the age correction of stature should reflect the pattern of age‐related stature loss to minimize estimation error. An equation that includes a continuous and linear age correction through the entire adult age range [Eq. (1)] results in curvilinear stature estimation error. This curvilinear stature estimation error can be largely avoided by applying a second linear equation [Eq. (2)] to only individuals older than 40 years. Our third equation [Eq. (3)], based on younger individuals who have not lost stature, can be used to estimate maximum stature. This equation can also be applied to individuals of unknown or highly uncertain age, because it provides reasonably accurate estimates until about 60/70 years at least for males. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22332   open full text
• Sex estimation based on deciduous and permanent dentition in a contemporary spanish population.
  Joan Viciano, Sandra López‐Lázaro, Inmaculada Alemán.
  American Journal of Physical Anthropology. July 30, 2013
  Sex estimation of skeletal remains with satisfactory allocation accuracy represents an essential step in reconstructing the biological profile of unknown individuals in archaeological research and forensic practice. Teeth are among the most frequently recovered physical elements of an individual that remain after death due to their hardness, durability, and resistance to postmortem insults. This study was based on the deciduous and permanent dentition of 269 individuals (150 males and 119 females) from the Granada osteological collection of identified infants, young children, and adults (Granada, Spain). Mesiodistal, buccolingual, and diagonal crown and cervical diameters of both dentitions were measured, and logistic regression analyses were performed to create equations for sex discrimination. The results show that the first and second deciduous molars and the permanent canines are the teeth with the greatest sexual dimorphism, providing percentages of correct assignment of sex between 78.1 and 93.1% in deciduous dentition and between 79.4 and 92.6% in permanent teeth, depending on the dimensions used. The results indicate that this method may be applicable as an adjunct with other accepted procedures for sex estimation when fragmentary skeletal remains are encountered in archaeological excavations and in forensic contexts. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22324   open full text
• Brief communication: Effect of nomadic subsistence practices on lactase persistence associated genetic variation in Kuwait.
  Sarah Catherine Hill, Talal Ramadan Mohammad, Toomas Kivisild.
  American Journal of Physical Anthropology. July 30, 2013
  Lactase persistence (LP)—the ability to digest lactose in adulthood—is paradigmatic of Holocenic dietary change affecting the evolutionary trajectory of specific populations. Kuwait represents one location of high LP where the variation in associated genomic regions has not been examined. Here, we present new sequence data from a 427 bp amplicon 14 kb upstream of the LCT (lactase) gene for two Bedouin tribal populations, the Ajman and Mutran. We estimate the frequency of known LP associated alleles and discuss the impact of nomadic‐pastoralism on the associated genetic variation. We observe high frequency (56% on average) of the −13,915*G allele in both tribes, which is consistent with the high prevalence of LP in Kuwait. Whilst LP associated alleles occur in Kuwait at a similar frequency to other regional populations, we suggest that the −13,915*G allele frequency among the Kuwaiti Bedouin may be higher than among non‐Bedouin Kuwaitis, possibly due to greater historical reliance on milk consumption or genetic drift. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22313   open full text
• Instrumental social support and women's body composition in El Alto, Bolivia.
  Kathryn Hicks.
  American Journal of Physical Anthropology. July 30, 2013
  Instrumental social support, or aid in the form of labor or money, may exert a positive influence on economic welfare and food security. Several investigators have found a positive relationship between social support and nutritional status, while others have found a negative association between social support and central adiposity. In the rural Andes, extra‐household economic cooperation has long been an important adaptive strategy, and the breakdown of these relationships is one reason for high rates of rural‐to‐urban migration, including to the Bolivian city of El Alto. This research investigates the influence of instrumental support on women's body composition. Information was collected on individual perception of instrumental support and anthropometric indicators of nutritional status including percent body fat (bioelectrical impedance analysis (BIA)), BMI, and distribution of fat on trunk relative to limbs (Ratio of subscapular to triceps skinfold (STR)), and multiple linear regression analysis used to test the prediction that instrumental social support is positively related to body fat stores. Controlling for age and household socioeconomic status, perceived access to one or more sources of instrumental support was positively and significantly related to overall levels of adiposity. There is no evidence that STR mediates the relationship between instrumental social support and body composition. This analysis offers support for the prediction that economic social support has direct effects on women's energy stores. The interpretation of these results is somewhat ambiguous given the high levels of overweight and obesity in this population. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22327   open full text
• Genetic evidence does not support an etruscan origin in Anatolia.
  Francesca Tassi, Silvia Ghirotto, David Caramelli, Guido Barbujani.
  American Journal of Physical Anthropology. July 30, 2013
  The debate on the origins of Etruscans, documented in central Italy between the eighth century BC and the first century AD, dates back to antiquity. Herodotus described them as a group of immigrants from Lydia, in Western Anatolia, whereas for Dionysius of Halicarnassus they were an indigenous population. Dionysius' view is shared by most modern archeologists, but the observation of similarities between the (modern) mitochondrial DNAs (mtDNAs) of Turks and Tuscans was interpreted as supporting an Anatolian origin of the Etruscans. However, ancient DNA evidence shows that only some isolates, and not the bulk of the modern Tuscan population, are genetically related to the Etruscans. In this study, we tested alternative models of Etruscan origins by Approximate Bayesian Computation methods, comparing levels of genetic diversity in the mtDNAs of modern and ancient populations with those obtained by millions of computer simulations. The results show that the observed genetic similarities between modern Tuscans and Anatolians cannot be attributed to an immigration wave from the East leading to the onset of the Etruscan culture in Italy. Genetic links between Tuscany and Anatolia do exist, but date back to a remote stage of prehistory, possibly but not necessarily to the spread of farmers during the Neolithic period. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22319   open full text
• Sex differences in 2D:4D and aggression in children and adolescents from five regions of Russia.
  Marina Butovskaya, Julija Fedenok, Valentina Burkova, John Manning.
  American Journal of Physical Anthropology. July 30, 2013
  The aim of this study was to consider digit ratio (2D:4D: a putative marker of prenatal testosterone and estrogen levels) and aggression in a sample of 1,452 children and adolescents (mean age 13.6 years) from five regions of Russia. The 2D:4D was calculated from direct measurements of the fingers, and aggression scores were obtained from completed Buss and Perry (J Pers Soc Psychol 63 (1992) 452–459) aggression questionnaires. The 2D:4D demonstrated significant sexual dimorphism, with lower 2D:4D in boys in all regions. Physical aggression scores were highest in boys, but verbal aggression, anger and hostility were highest in girls. The highest right hand 2D:4D in boys was found in the most northerly population (Central Russia Region). Our data revealed small, but highly significant negative correlations between right 2D:4D, right–left 2D:4D (DR‐L) and self‐ratings on physical aggression in boys, but not in girls. These relationships remained after considering Russian ethnics only, and controlling for region. We suggest that the associations may be due to sex differences in prenatal androgen secretion. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22337   open full text
• Paleodemographic age‐at‐death distributions of two Mexican skeletal collections: A comparison of transition analysis and traditional aging methods.
  Meggan Bullock, Lourdes Márquez, Patricia Hernández, Fernando Ruíz.
  American Journal of Physical Anthropology. July 30, 2013
  Traditional methods of aging adult skeletons suffer from the problem of age mimicry of the reference collection, as described by Bocquet‐Appel and Masset (1982). Transition analysis (Boldsen et al., 2002) is a method of aging adult skeletons that addresses the problem of age mimicry of the reference collection by allowing users to select an appropriate prior probability. In order to evaluate whether transition analysis results in significantly different age estimates for adults, the method was applied to skeletal collections from Postclassic Cholula and Contact‐Period Xochimilco. The resulting age‐at‐death distributions were then compared with age‐at‐death distributions for the two populations constructed using traditional aging methods. Although the traditional aging methods result in age‐at‐death distributions with high young adult mortality and few individuals living past the age of 50, the age‐at‐death distributions constructed using transition analysis indicate that most individuals who lived into adulthood lived past the age of 50. Am J Phys Anthropol, 2013. © 2013 Wiley Periodicals, Inc.

  July 30, 2013   doi: 10.1002/ajpa.22329   open full text
• New craniodental fossils of papionin monkeys from Cooper's D, South Africa.
  Kaila E. Folinsbee, Robert R. Reisz.
  American Journal of Physical Anthropology. July 18, 2013
  Papionin monkey fossils are common in the Plio‐Pleistocene aged karst cave deposits northwest of Johannesburg in South Africa. These deposits have yielded important primate and other vertebrate fauna since their discovery in the early part of the 20th century. In this article, we describe new primate cranial and dental specimens from excavations at the site of Cooper's D in the Sterkfontein Valley that date to around 1.5 million years ago. Unlike other localities in southern Africa, most of the new fossils are referred to Theropithecus oswaldi oswaldi, an extinct gramnivorous monkey related to the living gelada. Diagnostic features of T. o. oswaldi crania and teeth include large, thickly enameled molars with tall, columnar cusps, and high molar relief, an upright mandibular ramus, postorbital constriction, and anterior fusion of temporal lines. Also present in the new sample are teeth referred to Papio sp., which show low crowned bunodont molars, and a number of indeterminate papionin teeth and skull fragments. The presence of T. o. oswaldi at Cooper's D extends the list of known localities where the taxon is found, and may indicate the presence of an open, grassland environment in the area during the early Pleistocene. The abundance of theropith fossils at Cooper's suggests that Papio was not consistently the most common papionin in southern Africa over the past three million years. Am J Phys Anthropol 151:613–629, 2013. © 2013 Wiley Periodicals, Inc.

  July 18, 2013   doi: 10.1002/ajpa.22317   open full text
• Postnatal temporal bone ontogeny in Pan, Gorilla, and Homo, and the implications for temporal bone ontogeny in Australopithecus afarensis.
  Claire E. Terhune, William H. Kimbel, Charles A. Lockwood.
  American Journal of Physical Anthropology. July 18, 2013
  Assessments of temporal bone morphology have played an important role in taxonomic and phylogenetic evaluations of fossil taxa, and recent three‐dimensional analyses of this region have supported the utility of the temporal bone for testing taxonomic and phylogenetic hypotheses. But while clinical analyses have examined aspects of temporal bone ontogeny in humans, the ontogeny of the temporal bone in non‐human taxa is less well documented. This study examines ontogenetic allometry of the temporal bone in order to address several research questions related to the pattern and trajectory of temporal bone shape change during ontogeny in the African apes and humans. We further apply these data to a preliminary analysis of temporal bone ontogeny in Australopithecus afarensis. Three‐dimensional landmarks were digitized on an ontogenetic series of specimens of Homo sapiens, Pan troglodytes, Pan paniscus, and Gorilla gorilla. Data were analyzed using geometric morphometric methods, and shape changes throughout ontogeny in relation to size were compared. Results of these analyses indicate that, despite broadly similar patterns, African apes and humans show marked differences in development of the mandibular fossa and tympanic portions of the temporal bone. These findings indicate divergent, rather than parallel, postnatal ontogenetic allometric trajectories for temporal bone shape in these taxa. The pattern of temporal bone shape change with size exhibited by A. afarensis showed some affinities to that of humans, but was most similar to extant African apes, particularly Gorilla. Am J Phys Anthropol 151:630–642, 2013. © 2013 Wiley Periodicals, Inc.

  July 18, 2013   doi: 10.1002/ajpa.22318   open full text
• Weaning at Anglo‐Saxon raunds: Implications for changing breastfeeding practice in britain over two millennia.
  Hannah Haydock, Leon Clarke, Elizabeth Craig‐Atkins, Rachel Howcroft, Jo Buckberry.
  American Journal of Physical Anthropology. July 18, 2013
  This study investigated stable‐isotope ratio evidence of weaning for the late Anglo‐Saxon population of Raunds Furnells, Northamptonshire, UK. δ15N and δ13C values in rib collagen were obtained for individuals of different ages to assess the weaning age of infants within the population. A peak in δ15N values at about 2‐year‐old, followed by a decline in δ15N values until age three, indicates a change in diet at that age. This change in nitrogen isotope ratios corresponds with the mortality profile from the site, as well as with archaeological and documentary evidence on attitudes towards juveniles in the Anglo‐Saxon period. The pattern of δ13C values was less clear. Comparison of the predicted age of weaning to published data from sites dating from the Iron Age to the 19th century in Britain reveals a pattern of changing weaning practices over time, with increasingly earlier commencement and shorter periods of complementary feeding in more recent periods. Such a change has implications for the interpretation of socioeconomic changes during this period of British history, since earlier weaning is associated with decreased birth spacing, and could thus have contributed to population growth. Am J Phys Anthropol 151:604–612, 2013. © 2013 Wiley Periodicals, Inc.

  July 18, 2013   doi: 10.1002/ajpa.22316   open full text
• Diet and social status on Taumako, a Polynesian outlier in the Southeastern Solomon Islands.
  Rebecca L. Kinaston, Hallie R. Buckley, Andrew Gray.
  American Journal of Physical Anthropology. July 18, 2013
  Stable isotopes (δ13C, δ15N, and δ34S) are used to characterize the diet of the adult individuals (n = 99) interred in the Namu burial ground located on the Polynesian outlier of Taumako (∼300–750 BP). Polynesian outliers are islands on the fringe of Remote Oceania that were inhabited by a back migration of populations from Polynesia during prehistory. As a result of admixture with nearby island communities, little is known about the social structure and social diversity of the prehistoric inhabitants of Taumako. The distribution of prestige grave goods within the Namu cemetery has been used as evidence to support the premise that Taumakoan social structure was stratified like Polynesian societies. Here we test the hypothesis that “wealthy” individuals and males will display isotopic ratios indicative of the consumption of “high status” foods in the Pacific islands such as pork, chicken, sea turtle, and pelagic fish. The isotope results suggest the δ34S values were diagenetically altered, possibly an effect of volcanism. The carbon and nitrogen stable isotope ratios indicate that the diet of all the individuals included a mixture of C3 terrestrial plant foods (likely starchy staples such as yam, taro, and breadfruit, in addition to nuts) and a variety of marine resources, including reef and pelagic fish. The stable isotope results indicate that wealthy individuals and males were eating more foods from higher trophic levels, interpreted as being high status animal foods. The socially differentiated food consumption patterns are discussed within a Pacific island context. Am J Phys Anthropol 151:589–603, 2013. © 2013 Wiley Periodicals, Inc.

  July 18, 2013   doi: 10.1002/ajpa.22314   open full text
• Male genetic structure and paternity in western lowland gorillas (Gorilla gorilla gorilla).
  Eiji Inoue, Etienne François Akomo‐Okoue, Chieko Ando, Yuji Iwata, Mariko Judai, Shiho Fujita, Shun Hongo, Chimene Nze‐Nkogue, Miho Inoue‐Murayama, Juichi Yamagiwa.
  American Journal of Physical Anthropology. July 18, 2013
  The male dispersal patterns of western lowland gorillas (WLGs, Gorilla gorilla gorilla) are not well understood. To determine whether most silverbacks stay close to their relatives, we analyzed autosomal and Y‐chromosomal microsatellites (STRs) in wild WLGs at Moukalaba, Gabon. We obtained STR genotypes for 38 individuals, including eight silverbacks and 12 adult females in an approximately 40 km2 area. Among them, 20 individuals were members of one identified group (Group Gentil; GG), including one silverback and six adult females. The silverback sired all 13 of the offspring in GG and no Y‐STR polymorphism within GG was found, as expected in a one‐male group structure. Over all silverbacks sampled, Y‐STR diversity was high considering the limited sampling area, and silverbacks with similar Y‐STR haplotypes were not always located in nearby areas. Although the misclassification rate of kinship estimates in this study was not negligible, there were no kin dyads among all silverbacks sampled. These results suggest that silverbacks born in the same group do not stay close to each other after maturation. The Y‐STR diversity in this study was similar to that of a previous study conducted in an area that was approximately 150 times larger than our study area. Similarity of WLG Y‐STR diversity between studies at different sampling scales suggests that male gene flow may not be geographically limited. These results suggest that WLG males normally disperse from their natal areas after maturation, at least, in Moukalaba. Am J Phys Anthropol 151:583–588, 2013. © 2013 Wiley Periodicals, Inc.

  July 18, 2013   doi: 10.1002/ajpa.22312   open full text
• European pliopithecid diets revised in the light of dental microwear in Pliopithecus canmatensis and Barberapithecus huerzeleri.
  Daniel DeMiguel, David M. Alba, Salvador Moyà‐Solà.
  American Journal of Physical Anthropology. July 18, 2013
  Pliopithecinae and Crouzeliinae (Primates: Pliopithecidae) are distinguished dentally by the sharper crests, more compressed cusps, larger foveae, and narrower molars of the latter. Traditionally, such differences were qualitatively related to increased folivory in crouzeliines. This was subsequently disproved by microwear and shearing crest analyses, indicating that all pliopithecids were soft‐fruit eaters, except for the more folivorous crouzeliine Barberapithecus. This seems however at odds with the occlusal morphology of the latter, intermediate between those of Pliopithecus and the more derived crouzeliine Anapithecus. To further assess dietary evolution in this group, we report results of dental microwear for two Iberian pliopithecids: Pliopithecus canmatensis, from several Abocador de Can Mata localities (11.8–11.7 Ma, MN8), and Barberapithecus huerzeleri from Castell de Barberà (ca. 11.2–10.5 Ma, MN8, or MN9). Contrary to previously published results, our analyses suggest that all pliopithecids, including Barberapithecus, had a frugivorous diet with a significant sclerocarpic component—apparently more marked in some pliopithecines (such as P. canmatensis) than in the crouzeliine Anapithecus. If our interpretation is correct, it would mean that, within the framework of a frugivorous diet with some hard‐object feeding, crouzeliine dental evolution would have been driven by selection pressures towards increased soft‐fruit consumption instead of folivory. Dental differences between pliopithecids and hominoids with a significant sclerocarpic component (i.e., orangutans) might be related to phylogenetic constraints, different food‐processing methods and/or fracture toughness of hard foods consumed. Although additional research would be required, results suggest that dietary niche partitioning played a significant role in the radiation of European pliopithecids. Am J Phys Anthropol 151:573–582, 2013. © 2013 Wiley Periodicals, Inc.

  July 18, 2013   doi: 10.1002/ajpa.22299   open full text
• Taxonomic attribution of the La Grive hominoid teeth.
  Miriam Pérez de los Ríos, David M. Alba, Salvador Moyà‐Solà.
  American Journal of Physical Anthropology. June 11, 2013
  The two hominoid teeth—a central upper incisor (NMB G.a.9.) and an upper molar (FSL 213981)—from the Middle Miocene site of La Grive‐Saint‐Alban (France) have been traditionally attributed to Dryopithecus fontani (Hominidae: Dryopithecinae). However, during the last decade discoveries in the Vallès‐Penedès Basin (Spain) have shown that several hominoid genera were present in Western Europe during the late Middle Miocene. As a result, the attribution of the dryopithecine teeth from La Grive is not as straightforward as previously thought. In fact, similarities with the upper incisor of Pierolapithecus have led to suggestions that either the latter taxon is present at La Grive, or that it is a junior synonym of Dryopithecus. Here, we re‐describe the La Grive teeth and critically revise their taxonomic assignment based on metrical and morphological comparisons with other Middle to Late Miocene hominoids from Europe and Turkey, with particular emphasis on those from the Vallès‐Penedès Basin. Our results suggest that the I1 differs in several respects from those of Pierolapithecus and Hispanopithecus, so that an attribution to either Dryopithecus or Anoiapithecus (for which this tooth is unknown) seems more likely. The molar, in turn, most likely corresponds to the M1 of a female individual. Compared to other Middle Miocene taxa, its occlusal morphology enables its distinction from Pierolapithecus, whereas relative crown height agrees well with Dryopithecus. Therefore, based on available evidence, we support the traditional attribution of the La Grive hominoid to D. fontani. Am J Phys Anthropol 151:558–565, 2013. © 2013 Wiley Periodicals, Inc.

  June 11, 2013   doi: 10.1002/ajpa.22297   open full text
• Masculinization of the eruption pattern of permanent mandibular canines in opposite sex twin girls.
  Tuomo Heikkinen, Virpi Harila, Juha S. Tapanainen, Lassi Alvesalo.
  American Journal of Physical Anthropology. June 11, 2013
  The aim of this study is to explore the effect of prenatal androgenization on the clinical eruption of permanent teeth expressing dimorphism and bimaturism. The eruption curves of permanent teeth (except third molars), including those that make up the canine complex (permanent canines, lower first premolars), are compared among opposite sex twins (OS twins) relative to single‐born boys and girls. The comparisons are made with regard to three phases of eruption (pierced mucosa, half‐ erupted, and completely erupted) from a cross‐sectional sample of dental casts, using Kaplan–Meier survival and Cox regression analyzes. The casts were collected from 2159 school children from the US Collaborative Perinatal Project, including 39 pairs of OS‐twins, of which 12 pairs (30.8%) were Euro‐Americans and 27 pairs (69.2%) were of African‐American ancestry. The eruption patterns of the incisors, upper first molars, and lower canines were found to be significantly masculinized (delayed) among OS twin girls. The differences in most other teeth were either not significant, or the number of observations of active eruption phases were too few, such as in the upper first molars and incisors, to yield strong evidence and meaningful results. The masculinization of the tooth eruption pattern in OS twin girls is intriguing because of the lower canine responses during puberty, as well as canine primordial formation during early fetal androgenization of their co‐twin during the 8th to 14th gestational weeks. The present results offer a challenge for future research exploring tooth eruption mechanisms, and may also highlight some cases of delayed or ectopic canines, which are biased toward females. Am J Phys Anthropol 151:566–572, 2013. © 2013 Wiley Periodicals, Inc.

  June 11, 2013   doi: 10.1002/ajpa.22298   open full text
• Bite force and occlusal stress production in hominin evolution.
  Carolyn M. Eng, Daniel E. Lieberman, Katherine D. Zink, Michael A. Peters.
  American Journal of Physical Anthropology. June 11, 2013
  Maximum bite force affects craniofacial morphology and an organism's ability to break down foods with different material properties. Humans are generally believed to produce low bite forces and spend less time chewing compared with other apes because advances in mechanical and thermal food processing techniques alter food material properties in such a way as to reduce overall masticatory effort. However, when hominins began regularly consuming mechanically processed or cooked diets is not known. Here, we apply a model for estimating maximum bite forces and stresses at the second molar in modern human, nonhuman primate, and hominin skulls that incorporates skeletal data along with species‐specific estimates of jaw muscle architecture. The model, which reliably estimates bite forces, shows a significant relationship between second molar bite force and second molar area across species but does not confirm our hypothesis of isometry. Specimens in the genus Homo fall below the regression line describing the relationship between bite force and molar area for nonhuman anthropoids and australopiths. These results suggest that Homo species generate maximum bite forces below those predicted based on scaling among australopiths and nonhuman primates. Because this decline occurred before evidence for cooking, we hypothesize that selection for lower bite force production was likely made possible by an increased reliance on nonthermal food processing. However, given substantial variability among in vivo bite force magnitudes measured in humans, environmental effects, especially variations in food mechanical properties, may also be a factor. The results also suggest that australopiths had ape‐like bite force capabilities. Am J Phys Anthropol 151:544–557, 2013. © 2013 Wiley Periodicals, Inc.

  June 11, 2013   doi: 10.1002/ajpa.22296   open full text
• Sex determination of human skeletal populations using latent profile analysis.
  Nicholas V. Passalacqua, Zhen Zhang, Steven J. Pierce.
  American Journal of Physical Anthropology. June 11, 2013
  Accurately estimating biological sex from the human skeleton can be especially difficult for fragmentary or incomplete remains often encountered in bioarchaeological contexts. Where typical anatomically dimorphic skeletal regions are incomplete or absent, observers often take their best guess to classify biological sex. Latent profile analysis (LPA) is a mixture modeling technique which uses observed continuous data to estimate unobserved categorical group membership using posterior probabilities. In this study, sex is the latent variable (male and female are the two latent classes), and the indicator variables used here were eight standard linear measurements (long bone lengths, diaphyseal and articular breadths, and circumferences). Mplus (Muthén and Muthén: Mplus user's guide, 6th ed. Los Angeles: Muthén & Muthén, 2010) was used to obtain maximum likelihood estimates for latent class membership from a known sample of individuals from the forensic data bank (FDB) (Jantz and Moore‐Jansen: Database for forensic anthropology in the United States 1962–1991, Ann Arbor, MI: Interuniversity Consortium for Political and Social Research, 2000) (n = 1,831), yielding 87% of correct classification for sex. Then, a simulation extracted 5,000 different random samples of 206 complete cases each from the FDB (these cases also had known sex). We then artificially imposed patterns of missing data similar to that observed in a poorly preserved bioarchaeological sample from Medieval Asturias, Spain (n = 206), and ran LPA on each sample. This tested the efficacy of LPA under extreme conditions of poor preservation (missing data, 42%). The simulation yielded an average of 82% accuracy, indicating that LPA is robust to large amounts of missing data when analyzing incomplete skeletons. Am J Phys Anthropol 151:538–543, 2013. © 2013 Wiley Periodicals, Inc.

  June 11, 2013   doi: 10.1002/ajpa.22295   open full text
• Maternal admixture and population structure in Mexican–Mestizos based on mtDNA haplogroups.
  Gabriela Martínez‐Cortés, Joel Salazar‐Flores, Javier Haro‐Guerrero, Rodrigo Rubi‐Castellanos, Jésus S. Velarde‐Félix, José F. Muñoz‐Valle, Mavil López‐Casamichana, Eduardo Carrillo‐Tapia, Luis M. Canseco‐Avila, Claudio M. Bravi, Mauro López‐Armenta, Héctor Rangel‐Villalobos.
  American Journal of Physical Anthropology. June 11, 2013
  The maternal ancestry (mtDNA) has important applications in different research fields, such as evolution, epidemiology, identification, and human population history. This is particularly interesting in Mestizos, which constitute the main population in Mexico (∼93%) resulting from post‐Columbian admixture between Spaniards, Amerindians, and African slaves, principally. Consequently, we conducted minisequencing analysis (SNaPshot) of 11 mitochondrial single‐nucleotide polymorphisms in 742 Mestizos of 10 populations from different regions in Mexico. The predominant maternal ancestry was Native American (92.9%), including Haplogroups A, B, C, and D (47, 23.7, 15.9, and 6.2%, respectively). Conversely, European and African ancestries were less frequent (5.3 and 1.9%, respectively). The main characteristics of the maternal lineages observed in Mexican–Mestizos comprised the following: 1) contrasting geographic gradient of Haplogroups A and C; 2) increase of European lineages toward the Northwest; 3) low or absent, but homogeneous, African ancestry throughout the Mexican territory; 4) maternal lineages in Mestizos roughly represent the genetic makeup of the surrounding Amerindian groups, particularly toward the Southeast, but not in the North and West; 5) continuity over time of the geographic distribution of Amerindian lineages in Mayas; and 6) low but significant maternal population structure (FST = 2.8%; P = 0.0000). The average ancestry obtained from uniparental systems (mtDNA and Y‐chromosome) in Mexican–Mestizos was correlated with previous ancestry estimates based on autosomal systems (genome‐wide single‐nucleotide polymorphisms and short tandem repeats). Finally, the comparison of paternal and maternal lineages provided additional information concerning the gender bias admixture, mating patterns, and population structure in Mestizos throughout the Mexican territory. Am J Phys Anthropol 151:526–537, 2013. © 2013 Wiley Periodicals, Inc.

  June 11, 2013   doi: 10.1002/ajpa.22293   open full text
• Cranial morphological variation among contemporary Mexicans: Regional trends, ancestral affinities, and genetic comparisons.
  Cris E. Hughes, Meredith L. Tise, Lindsay H. Trammell, Bruce E. Anderson.
  American Journal of Physical Anthropology. June 11, 2013
  Genetic research has documented geographical variation within Mexico that corresponds to trends in ancestry admixture from postcolonial times on. The purpose of this study is to determine whether craniometric variation among contemporary Mexicans is comparable to that reported in genetic studies. Standard osteometric measurements were taken on 82 male crania derived from forensic cases, with geographic origins of the specimens spanning over two‐thirds of Mexico's states. To study similarities in regional clustering patterns with genetic data, k‐means clustering analyses were performed, followed by chi‐square tests of association between cluster assignments and geographic region of origin. Normal mixtures analyses were performed, centered on three “ancestral” sample proxies to estimate classification probability to each ancestry. The results demonstrate that the cranial morphological sample data cluster similarly to the regional groupings inferred from the genetic data. Additionally, the results indicate a gradient trend in population structure for contemporary Mexicans, with the proportion of Amerindian ancestry increasing from North to South while, conversely, European ancestry proportion estimates increase from South to North. Furthermore, the probabilities for classification of African ancestry remained low across the regions, again reflecting the results for the genetic data. Cranial morphological variation is well aligned with the genetic data for describing broad trends among Mexican populations, as well as yielding comparable estimates of general ancestry affiliations that reflect Mexico's history of Spanish contact and colonialism. Am J Phys Anthropol 151:506–517, 2013. © 2013 Wiley Periodicals, Inc.

  June 11, 2013   doi: 10.1002/ajpa.22288   open full text
• Testing functional and morphological interpretations of enamel thickness along the deciduous tooth row in human children.
  Patrick Mahoney.
  American Journal of Physical Anthropology. June 01, 2013
  The significance of a gradient in enamel thickness along the human permanent molar row has been debated in the literature. Some attribute increased enamel thickness from first to third molars to greater bite force during chewing. Others argue that thicker third molar enamel relates to a smaller crown size facilitated by a reduced dentin component. Thus, differences in morphology, not function, explains enamel thickness. This study draws on these different interpretive models to assess enamel thickness along the entire human deciduous tooth row. Average enamel thickness (AET), the area and proportion of crown enamel and dentin, and a crown size proxy are calculated for incisors, canines, and molars. Allometric scaling relationships are assessed within each tooth class, and then comparisons are undertaken along the row. Generally, AET was correlated with crown size and scaled with isometry, except for second molars which scaled with positive allometry. Mean AET increased along the row and was greater on molars, where bite forces are reported to be higher. Second molars combined the largest crown size with the thickest enamel and the smallest proportion of dentin, which is consistent with a reduction in the potential for cusp fracture under high bite forces. Resistance to wear may also account for some enamel thickness variation between tooth classes. Dental reduction did not explain the trend in AET from central to lateral incisors, or from first to second molars. The gradient in AET along the deciduous tooth row is partly consistent with a functional interpretation of enamel thickness. Am J Phys Anthropol 151:518–525, 2013. © 2013 Wiley Periodicals, Inc.

  June 01, 2013   doi: 10.1002/ajpa.22289   open full text