Events Detail

Speaker:
Dr. James Brooks, Kyoto University

Comparative studies with apes and equines on the evolution of group-mindedness

While humans’ psychological disposition towards both large scale cooperation and intergroup competition has long been recognized, the majority of comparative psychology research has focused on the dyadic level. I here review a set of our recent studies focusing on the evolution of inherently group-level social behaviour with bonobos, chimpanzees, and domestic horses. Bonobos and chimpanzees are humans’
two closest relatives, and, despite diverging only recently, show considerable differences in group-based behaviour in wild contexts.
Horses are relatively distantly related to us phylogenetically, but share with us an evolutionary history of domestication and show group-level herding behaviour with multi-level social structure. Methods focused on measurement of changes to social attention as well as naturalistic social behaviour following administration of exogenous oxytocin or saline placebo, along with observation of behavioural responses to outgroup stimuli. On the whole, evidence suggests that oxytocin supports species-typical sociality, including in group-level contexts, and that, as in humans, perceived outgroup threat promotes ingroup cohesion in our closest relatives. These results provide empirical support for some existing hypotheses about the relation between intergroup competition and group cooperation, highlight areas of study warranting continued future investigation, and suggest that the evolutionary origins of human group-mindedness can, in part, be understood through a history of intergroup competition supported by the oxytocin system.