Reconciliation in Primates

■ Abstract Sociality is favored by natural selection because it enhances group members’ access to valued resources or reduces their vulnerability to predators, but group living also generates conflict among group members. To enjoy the benefits of sociality, group living animals must somehow overcome the costs of conflict. Nonhuman primates have developed an effective mechanism for resolving conflicts: They participate in peaceful postconflict (PC) reunions with former opponents. These peaceful PC interactions are collectively labeled reconciliation. There is a broad consensus that peaceful contacts among former opponents relieve stressful effects of conflict and permit former opponents to interact peacefully. Primates may reconcile to obtain shortterm objectives, such as access to desirable resources. Alternatively, reconciliation may preserve valuable relationships damaged by conflict. Some researchers view these explanations as complementary, but they generate different predictions about the patterning of reconciliation that can be partially tested with available data. There are good reasons to question the validity of the relationship-repair model, but it remains firmly entrenched in the reconciliation literature, perhaps because it fits our own folk model of how and why we resolve conflicts ourselves. It is possible that the function of reconciliation varies within the primate order, much as other aspects of cognitive abilities do.