Abstract
Nonhuman primates are marked by well-developed prosocial and cooperative tendencies as reflected in the way they support each other in fights, hunt together, share food, and console victims of aggression. The proximate motivation behind such behaviour is not to be confused with the ultimate reasons for its evolution. Even if a behaviour is ultimately self-serving, the motivation behind it may be genuinely unselfish. A sharp distinction needs to be drawn, therefore, between 1) altruistic and cooperative behaviour with knowable benefits to the actor, which may lead actors aware of these benefits to seek them by acting cooperatively or altruistically, and 2) altruistic behaviour that offers the actor no knowable rewards. The latter is the case if return-benefits occur too unpredictably, too distantly in time, or are of an indirect nature, such as increased inclusive fitness. The second category of behaviour can be explained only by assuming an altruistic impulse, which -- as in humans -- may be born from empathy with the recipient's need, pain, or distress. Empathy, a proximate mechanism for prosocial behaviour that makes one individual share another's emotional state, is biased the way one would predict from evolutionary theories of cooperation (i.e. by kinship, social closeness, and reciprocation). There is increasing evidence in nonhuman primates (and other mammals) for this proximate mechanism as well as for the unselfish, spontaneous nature of the resulting prosocial tendencies. This lecture reviews observational and experimental evidence for the reciprocity mechanisms that underlie cooperation among non-relatives, for inequity aversion as a constraint on cooperation, and the way defection is dealt with.
Frans BM de Waal, Director of the Living Links Center, part of the Yerkes National Primate Research Center, EMORY University, Atlanta, USA.
Don't miss Frans de Waal's Kristine Bonnevie lecture at 10.15 (Sophus Lie's auditorium) Thursday 2 September, and the free lunch with Frans de Waal outside the Kristine Bonnevies house at 12.00 Thursday 2 September.