Over evolutionary time, humans have come to inhabit a unique point on the two fundamental axes of animal sociality, competition and cooperation. Comparative research with chimpanzees, one of our closest living relatives, has shown that human prosociality often defies rational self-interest and that in fact, human cooperation extends far beyond the forms of collaboration we see in other species. This distinctive human feature has resulted not only in cooperative behavior but also in unique forms of cognition adapted for excelling in interactive contexts and navigating a complex social world. This trait is so integral to human interaction, that individuals ask the central questions of a decision-making agent – What should I do? What should I believe? – in fundamentally cooperative ways. At the same time, and maybe counterintuitively, our cooperative nature also gives rise to novel and especially powerful forms of competition among human individuals, coalitions, and whole groups.

Based on this framework, I ask two interrelated research questions: How are human skills and motivations for cooperation similar to and different from those of our closest living relatives, chimpanzees? How do human children, over the course of ontogeny, reliably develop species-specific cooperative skills and motivations and how does this process differ across populations?