Two main foci of my research are:
1. Intergroup interactions and social cognition. Specifically, I examine humans’ psychological adaptations for processing ethnic social categories using cross-cultural and developmental research. My primary geographic focus has been among agro-pastoralists in the Peruvian Altiplano along the Quechua-Aymara linguistic border
2. Cross-cultural variation in social effects on reproduction. I examine why and how family members and religiosity affect fertility outcomes across space and time. I also work on why social learning processes influence reproductive decision-making so much and how this can give rise to puzzling phenomena such as the demographic transition, below replacement fertility, and cross-site variation in life history decisions.
I am also starting projects on the origins of ritual participation at a new pilgrimage site, and inter-site variation in collective action on vicuña hunts, both in the Peruvian Altiplano.
See list of publications on Google Scholar