Using comparative phylogenetic analyses to study the evolution of human language and other behaviors
My research revolves around the evolution of human social behavior, which I study using both empirical field work and comparative approaches. In this talk I focus on the latter. I first present a phylogenetic analysis of human hygiene and social behavior as a test of Dunbar’s “vocal grooming” hypothesis for the evolution of language, for which I find no support. I then introduce a new phylogenetic supertree of almost 2000 human populations that combines numerous genetic and linguistic phylogenies and allows cross-cultural phylogenetic analyses to be conducted on large, global samples. This allows us to control for non-independence, and to estimate the contributions of population history as well as current ecology on trait variation. I briefly present four such analyses, all using the Standard Cross-Cultural Sample, a globally representative sample of 186 pre-industrial societies. The four studies analyze variation in marriage patterns, food sharing, alloparental care, and social complexity. Throughout I highlight methodological innovations and key theoretical insights.