Collaborative Research: Drivers and proxies of behavioral diversity in Late Pleistocene and Holocene hunter-gatherers

The goal of this project is to study the conditions under which people establish and maintain cultural boundaries. Ethnic and linguistic identity are central to human social organization and enable people to identify with other group members without personally knowing each of them. This "ethnolinguistic identity" encourages cooperation at a scale that allows humans to solve problems that could not be tackled with a smaller number of people but may also discourage cooperation between groups. Because cooperation is an ongoing source of human ingenuity and conflict today, it is essential to understand the conditions under which it first emerged and was maintained by our forager ancestors. Did populations become separate because they followed different patterns of resource use across the landscape? Was interaction then discouraged because of the development of cultural barriers? To what extent did ancient human groups share information and/or resources while maintaining biological and cultural boundaries? Archaeologists can now combine advances in ancient DNA, computational simulations, and ancient environmental reconstruction with analysis of cultural remains to understand the formation and consequences of ethnolinguistic identities in early human populations. This study enhances career opportunities and provide training for a postdoctoral researcher, graduate students, and undergraduates. By embedding the work in local communities, scientific training will occur within a multicultural research environment that builds essential skills needed for maximizing the benefits of a diverse STEM workforce. The research team will conduct research in two regions, where ancient DNA analysis has revealed that forager populations began to maintain separate biological groupings near the end of the last Ice Age cycle. The investigators will develop well-dated cultural and environmental records from sites around and including where ancient DNA has been discovered. The team will conduct new, high-resolution excavations and analyze the remains they recover alongside existing materials excavated using lower resolution methods in the 1970s. This increased detail will enable both datasets to be brought into alignment and maximize their information value to show if cultural remains such as stone artifacts, pigments, bone tools, and beads show evidence of emerging cultural differences between groups known from ancient DNA to have had little biological interaction. Using environmental data, the team will build simulation models of forager resource use to understand how often people would have encountered one another. They will use these models to test if interaction rates or cultural barriers better explain the lack of genetic exchange. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.