Social antecedents and consequences of rhythmic behaviours in chimpanzees (Pan troglodytes)

Recently there has been a growing interest in the rhythmic behaviours (RBs) of nonhuman animals, as a way of tracking the evolutionary origins of musicality. Dominant theories in the field link the emergence of human rhythmic abilities to demands for (1) flexible vocal learning (and thus specific audiomotor neural adaptations) or (2) social bonding and cooperation. Extant evidence from nonhuman species is, however, insufficient to substantiate these theories, and data from our closest genetic relatives - the chimpanzees - is extremely scarce. To address this issue, we tracked the range, contexts and consequences of chimpanzee RBs in an observational study conducted at Furuvik Zoo (Sweden), Kolmarden Zoo (Sweden) and MONA Foundation (Spain). Preliminary results (based on 18 observation hours from Furuvik) showed that RBs are frequent in chimpanzees (N = 239 bouts), and were produced primarily in a social context (89%). The majority of these social bouts had a social consequence (72%, p 0.05). RBs appear to accomplish a communicative function in chimpanzees, partially corroborating social theories on the evolutionary origins of human rhythmic abilities. (Less)