Distinguishing between living (animate) and nonliving (inanimate) things is essential for survival and successful reproduction. Animacy is widely recognized as a foundational dimension, appearing early in development, but its role in remembering is currently unknown. We report two studies suggesting that animacy is a critical mnemonic dimension and is one of the most important item dimensions ultimately controlling retention. Both studies show that animate words are more likely to be recalled than inanimate words, even after the stimulus classes have been equated along other mnemonically relevant dimensions (e.g., imageability and meaningfulness). Mnemonic "tunings" for animacy are easily predicted a priori by a functional-evolutionary analysis.