Animals know the importance of kissing and making up after a fight, an audience will be told at a Scottish university.
Reconciliation has been seen in many species
Professor Frans de Waal will discuss the importance of reconciliation in repairing social relationships in the animal world.
He said research among primates and non-primates had suggested that such behaviour was "widespread".
The eminent scholar will deliver the Irvine Lecture at St Andrews University on Monday.
Professor de Waal said: "Reconciliation - defined as a friendly reunion between two individuals following conflict - has been confirmed in many different primate species, in both captivity and the field, both experimentally and observationally.
"Chimpanzees, for instance, kiss and embrace after fights.
"Reconciliation has also been demonstrated in non-primates, suggesting that the phenomenon is widespread indeed."
He said there was good evidence that it led to the repairing of social relationships.
Professor de Waal will discuss how aggression can be used as a negotiation tool and how parties can make their respective claims and intentions clear without undermining the relationship.
He is professor of psychology and director of Living Links at the Yerkes Primate Centre, Emory University, in Georgia.
Professor de Waal received the Los Angeles Times Book Award for Peacemaking among Primates, a popularized account of 15 years of research on conflict resolution in non-human primates.
His other books include Chimpanzee Politics, Bonobo: The Forgotten Ape and My Family Album: Thirty Years of Primate Photography.