Human self-domestication and the evolution of prosody

Human self-domestication refers to a new evolutionary hypothesis about human origins. According to this view, humans have experienced changes that are similar to those observed in domesticated mammals and that have provided us with many of the behavioural, and perhaps cognitive pre-requisites for supporting our complex social practices and advanced culture. At the core of this hypothesis is the claim that self-domestication is triggered by (and entails) a reduction in reactive aggression responses. The human self-domestication hypothesis has been recently used to explain how grammars became more sophisticated via a cultural mechanism. Nonetheless, less research has been done in the domain of phonology, even though animal evidence suggests that domestication favours call complexity too. In this paper, we hypothesise about the effects of our increased self-domestication on human prosody. We argue for a progressive complexification of prosody that parallels (and might be involved in a positive feed-back loop with) the complexification of grammar in response to a reduction in reactive aggression. We build on evidence of diverse nature, from language typology to brain function to language acquisition studies.