The emergence of cooperative behaviors, norms, and strategies across five diverse societies.

Abstract

Human cooperation involves a set of interconnected behaviors that develop in conjunction with the cultural environment. Despite recent advances in Western, industrialized contexts, we know far less about how cooperative behaviors emerge across cultures, how normative environments shape their development, and how these behaviors relate to one another. Here, we examined the development of four cooperative behaviors-fairness, trustworthiness, forgiveness, and honesty-in children (<i>N</i> = 413) aged 5 to 13 from five societies: urban United States, rural Uganda, Canada, Peru, and the hunter-horticulturalist Shuar of Ecuador. We also collected normative judgments from peers (<i>N</i> = 163) and adults (<i>N</i> = 86) of each community. We find substantial variation in cooperative behaviors and norms across populations, but, more generally, that children's behaviors and norms tend to converge toward community-specific norms in middle childhood. We also identify three cooperative strategies-maximization, generic cooperation, and partner-contingent cooperation-whose prevalence shifts with age and differs across societies. Together, these findings illuminate how cooperative behavior develops within and across cultures.