Th e Evolution of Morality: Which Aspects of Human Moral Concerns Are Shared With Nonhuman Primates?

Morality is a critical part of human society. This chapter explores the origins of human morality by examining whether nonhuman primate species share aspects of fi ve domains thought to be important in human moral behavior—concerns involving harm, fairness, hierarchy, ingroup allegiance, and purity. Behaviors in the harm domain have received the most attention from researchers, and converging lines of evidence suggest that some primates express harm concerns. The domain of fairness has become a recent focus of primate research, with active debate about whether closely related primates share human-like concerns. Moral behaviors regarding ingroup allegiance, authority, and purity have received the least attention in nonhuman species, though recent work suggests that research with primates might productively pursue the ingroup allegiance and authority domains. Future primate research will continue to elucidate the nature of human morality, and should include an increased focus on the previously neglected domains of ingroup and hierarchy.