Why collective music-making is sometimes rare: A study of four indigenous societies

Current prominent music evolution theories suggest music evolved as a participatory group activity, whose adaptive functions were strengthening and/or signaling social cohesion. However, the prevalence of collective music-making varies substantially across societies, and in some cases is exceptionally rare. Here, we consider hypotheses for three factors which could attenuate collective music-making: diminished collective action more generally, an emphasis on musical expertise, and solo-oriented musical styles. We examine data related to these hypotheses in four societies in which collective music-making is rare: the Tsimane of lowland Bolivia, the Ache of eastern Paraguay, the Ayoreo of Bolivia and Paraguay, and the Tuvans of the Russian Republic of Tyva. Our results suggest that the scale and religiosity of collective action are the most important factors related to the overall degree of collective music-making in these cultures. The effect of musical expertise was mostly limited to the dominance of shamans in religious contexts, while well-developed solo musical styles did not necessarily prevent group performance in other social settings. We also note the importance of cultural loss due to influence of invading colonial and imperial forces in diminishing indigenous forms of collective music-making. Notably, in all the cases we consider, episodes of some form of collective music-making do (or historically did) occur during important social events, a fact which supports the group-functionalist view. Our findings also point to the centrality and ubiquity of the religious function of music, and suggest this aspect of musical behavior needs to be better addressed by evolutionary theories of music.