Evolutionary models of music: From sexual selection to group selection

Ever since the publication of Darwin's Descent of Man in 1871, the survival value of music for the individual has been placed into question. Darwin's solution to this problem was to argue that music evolved by sexual selection as a courtship device to increase reproductive success. He envisioned music as functioning analogously to the courtship songs and advertisement calls of many animal species, most of which are performed exclusively by males during a breeding season. However Darwin's thinking predated the comparative study of world music-cultures, which developed only in the late 19th century. The 20th century anthropological study of music has been overwhelmingly group-functionalist in its thinking. Music is almost exclusively described in terms of its manifold roles in supporting group function - with regard to both within-group cooperation and between-group competitiveness. In this essay, I criticize the sexual selection model of music and attempt to channel the group-functionalist thinking of the ethnomusicology literature into a group selection model. Music is a powerful device for promoting group identity, cognition, coordination and catharsis, and it has a host of design features that reflect its strong role in supporting cooperation and synchronization at the group level, features such as the capacity for pitch blending and the use of isometric rhythms I argue that music and group rituals co-evolved during human evolution such that ritual developed as an information system and music its reinforcement system. Music is a type of social "reward" system, analogous to the neuromodulatory systems of the brain. This view accounts for music's universal association to ritual activities as well as its psychologically rewarding properties.