Cristina Moya: University of California, Davis

While many social species are group living, linguistically or symbolically marked social groups, characterized by large repertoires of shared cultural norms and behaviours, are uniquely human. However, the evolutionary relevance and psychological underpinnings of such ethnic groups remains debated. In this talk, I will examine the possibility that the way humans learn about ethno-linguistic boundaries reveal the structure of adaptations for reasoning about these. I report on psychological and ethnographic research from the Quechua-Aymara border in the Peruvian altiplano, and cross-cultural comparative work that speak to these questions. Results reveal 1) the importance of distinguishing between functionally independent intergroup phenomena such as stereotyping and cooperation, 2) that children are prone to develop believe that linguistic boundaries are important and fixed, and 3) that cultural evolutionary processes are likely more important than genetically evolved biases in determining the form of ethnic boundaries. Further implications for models of human social evolution will be discussed.