The scope of culture in chimpanzees, humans and ancestral apes

Abstract

More studies have focused on aspects of chimpanzee behaviour and cognition relevant to the evolution of culture than on any other species except our own. Accordingly, analysis of the features shared by chimpanzees and humans is here used to infer the scope of cultural phenomena in our last common ancestor, at the same time clarifying the nature of the special characteristics that advanced further in the hominin line. To do this, culture is broken down into three major aspects: the large scale, population-level patterning of traditions; social learning mechanisms; and the behavioural and cognitive contents of culture. Each of these is further dissected into subcomponents. Shared features, as well as differences, are identified in as many as a dozen of these, offering a case study for the comparative analysis of culture across animal taxa and a deeper understanding of the roots of our own cultural capacities.

Figure 1.

Features of culture shared by chimpanzees, humans and (by inference) their common ancestor, and features of culture distinctive in humans. Features (rows) are nested under three main headings (see text for extended discussion). Images represent examples discussed in the text: further explanation for each numbered image is given in the electronic supplementary material.

Figure 2.

Spread of experimentally seeded, multiple traditions generating four chimpanzee ‘cultures’. At each pair of locations, alternative techniques were experimentally seeded in a single individual and spread locally. Each column represents a single chimpanzee, with hatching corresponding to the alternative techniques seeded in the leftmost individual in each case. At Yerkes, row 1 = lift versus slide methods to open door in ‘doorian fruit’, run as a diffusion chain [18]; row 2 = poke versus lift panpipes techniques spread in an open (unconstrained) diffusion [17]; row 3 = bucket versus pipe posting option for tokens in an open diffusion [19]; row 4 = hand-clasp grooming, which arose and spread spontaneously in only Yerkes FS1 community. At Bastrop, row 1 = fish-probe versus fish-slide techniques; row 2 = turn-ip-slide versus turn-ip-ratchet techniques, used to extract food from two different devices; each technique spread to a second group (middle) and then a third (bottom) [20].