Prosocial behaviour in animals: the influence of social relationships, communication and rewards

► Overall, primates in close relationships were more likely to behave prosocially. ► In many species, prosociality was more likely to be shown by dominant individuals. ► When recipients showed interest in rewards, prosociality was less likely. ► A greater benefit for the recipient than the donor often inhibited prosociality. ► Acknowledging these trends will aid in the reconstruction of prosocial evolution.