Data_Despotism promotes cooperation through enhanced interdependencies in non-human primate societies

Cooperation is the cornerstone of human societies, and its emergence is firmly linked to enhanced tolerance and egalitarianism. However, evidence of profuse cooperation in less tolerant and despotic societies challenges this predominant view. The overarching interdependency hypothesis may resolve the conundrum. It posits that group-level interdependencies, like strength in numbers in colonially nesting species or allomaternal care in cooperatively breeding species, promote indiscriminate cooperation through enhanced tolerance. Crucially, this hypothesis also predicts that dyadic interdependencies like friendships, nepotistic biases, or coalitions, selectively enhance tolerance, fostering discriminate cooperation in despotic species. Species belonging to Macaca, due to their remarkable variation in tolerance, hierarchy steepness, nepotistic biases, and coalitionary tendencies but similarities in social organizations, provide a scope for testing the interdependency hypothesis. In social group settings, we experimentally study cooperation, prosociality, and tolerance in six macaque species along a despotic–egalitarian gradient. Our findings reveal higher dyadic cooperation in despotic than egalitarian societies, yet this is restricted to a few partners. Prosociality, kinship, and tolerance positively predict cooperation. Further, agent-based models demonstrate that despotic societies have fewer but more stable bonds and, thus, higher dyadic interdependencies than egalitarian ones. Our results show that interdependencies facilitate the emergence and maintenance of cooperation.