Description:
<jats:title>Significance</jats:title>
<jats:p>The evolution of culture is well-documented in the human archeological and fossil records, but equivalent data are absent for nonhuman primates. Here, we use modern variation to learn about processes of temporal evolution by measuring nestedness across human and great ape “cultural repertoires.” Cultural assemblages are nested if cultures with a small repertoire of traits tend to comprise a proper subset of traits present in more complex cultures. We find a significant degree of nestedness in human and chimpanzee cultural repertoires, but not for orangutans. Our findings are consistent with a sequential “layering” of culture in humans and chimpanzees only, suggesting that the traits required for sequential cultural evolution first appeared in the last common ancestor of these species.</jats:p>