This article explores the feeding and territorial behaviour of the wild camelids – guanacos and vicuñas – consumed by the inhabitants of the Dry Puna during the Early and Mid‐Holocene, as a way to deal with the strategies for resource exploitation employed by these human groups. We present 38 stable isotope values (δ13C and δ15N) generated from bone collagen extracted from the faunal remains obtained from the Hornillos 2 archaeological site (Susques, Jujuy Province, Argentina). These bone assemblages were recovered from nine layers that comprise human occupations corresponding to both periods (from 9710 to 6130 years bp). These data will be discussed considering ecological and ethological information about wild camelids, especially regarding territorial behaviour and dietary selectiveness of vicuñas and guanacos that currently inhabit the Puna. Finally, the trends and patterns identified in these isotopic evidences will be analysed in the light of the environmental and cultural changes that took place during the mentioned chronological span. Our results show no significant differences between camelid species, implying that δ13C and δ15N values of bone collagen constitute a poor taxonomical indicator, dismissing the possibility to identify the early incidence of human intervention in animal diet as an initial step to deal with the problem of domestication. In chronological terms, the δ15N results from Early and Mid‐Holocene show certain differences that can be linked to the preponderance of arid conditions during the latter. This underscores the usefulness of this line of evidence when evaluating environmental changes. On the other hand, the δ13C values show no substantial differences, meaning that carbon isotopic composition of bone collagen in mixed C3–C4 systems is not a reliable paleoenvironmental proxy. Copyright © 2013 John Wiley & Sons, Ltd.