We study the foundations of human social behaviors and focus on three overarching questions:
What are the origins of human cooperation?
Children are often characterized as purely selfish beings who have to be taught how to be helpful, share and cooperate with others. However, our research has shown that infants in the second year of life are already cooperative by helping others with their problems, working together, and sharing resources with them. This indicates that humans aren’t born egoists. Rather, both our selfish and altruistic tendencies likely reflect biological predispositions that can be honed over development.
Our work with children is complemented by studies with one of our closest living primate relatives – chimpanzees. Such research is crucial to disentangling the aspects of human cognition that are unique versus shared with our ape cousins. We have found that some forms of human-like cooperation—such as helping out others in need and collaborating in dyads — appear to be shared with chimpanzees. However, the cooperative behaviors of chimpanzees are not guided by a sense of fairness such as equal work – equal pay, something that young children acquire quickly.
What are the origins of the human sense of fairness?
Humans have a strong sense of how valuable resources should be shared. We study how children acquire a sense of fairness and how they are influenced by the adult norms of their social group. Children care about equality and merit early on, especially in contexts where they have worked together with others in a team: if collaborators worked equally hard, three-year-olds tend to share resources equally. Over development, children acquire local norms of what is regarded a fair share. Starting at school-age, many children endorse equality even if it requires a larger sacrifice on their part to establish an equal share. Last but not least, they stand up for others and intervene against unfair actions towards third parties.
What is the role of culture in children’s social development?
Many social behaviors differ widely across different cultural groups. Our research aims to reveal the factors that bring about similarities and differences in children’s development across diverse populations. We are particularly interested in the role of parental norms on child development, how group rituals influence children’s behaviors, and the foundation of reciprocity and fairness across the globe.
We have several projects where we have studied children’s cooperative behaviors and fairness norms in communities across the globe, including China, India, Mexico, Peru, Senegal, Uganda, and Vanuatu. We have found that there is quite some consistency in early forms of cooperation across very diverse populations, with children helping and collaborating early on. However, social norms shape development in culture-specific ways, with children acquiring local norms of fairness that can differ widely across different populations.