Human self-domestication and the evolution of prosody

Abstract

Human self-domestication refers to a new evolutionary hypothesis. 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 social practices and advanced culture. At the core of this hypothesis is the claim that self-domestication is triggered by a reduction in reactive aggression. Since the findings of increased complexity in the communicative signals of domesticated animals compared to their wild conspecific, the human self-domestication hypothesis has been used to account for the sophistication of the grammars of human languages. Nonetheless, less research has been done in the domain of phonology. In this talk, we apply this evolutionary model to the evolution of human prosody, arguing for a progressive complexification of prosody that parallels (and is triggered by) the complexification of grammar, also in response to a reduction in reactive aggression levels. Two different types of evidence support our claim: the parallel complexification of prosody and grammar found in emerging sign languages and the parallel sophistication of prosody and grammar during language acquisition, which in turn parallels an increased control over the mechanisms involved in reactive aggression.