Abstract
The diverse forms and functions of human music place obstacles in the way of an evolutionary reconstruction of its origins. In the absence of any obvious homologues of human music among our closest primate relatives, theorizing about its origins, in order to make progress, needs constraints from the nature of music, the capacities it engages, and the contexts in which it occurs. Here we propose and examine five fundamental constraints that bear on theories of how music and some of its features may have originated. First, cultural transmission, bringing the formal powers of cultural as contrasted with Darwinian evolution to bear on its contents. Second, generativity, i.e. the fact that music generates infinite pattern diversity by finite means. Third, vocal production learning, without which there can be no human singing. Fourth, entrainment with perfect synchrony, without which there is neither rhythmic ensemble music nor rhythmic dancing to music. And fifth, the universal propensity of humans to gather occasionally to sing and dance together in a group, which suggests a motivational basis endemic to our biology. We end by considering the evolutionary context within which these constraints had to be met in the genesis of human musicality.