Evolution of higher-level social organisation in humans and primates

Professor Grueter’s primary research interest is the evolution of sociality in humans and primates and the mechanisms that maintain cohesion in social groups. His particular interests revolve around the evolution of meta-group organization which describes cases in which individuals of different social units overcome hostility, interact and collaborate to varying degrees and in some cases form higher-level groupings.

Besides doing comparative analyses on primate sociality and analysing human ethnographic data,  Professor Grueter conducts observational and experimental research on three primate species that offer potential in elucidating the evolution of meta-group organisation:

• Mountain gorillas in Rwanda inhabit an area where there is high overlap among groups’ home ranges and encounters between different groups are relatively frequent. Professor Grueter studies them with the aim of determining the factors that prevent escalation of intergroup conflict, e.g. familiarity and relatedness among members of different groups or resource abundance in their home ranges.
• Golden snub-nosed monkeys in China form multilevel societies characterized by one-male units embedded within a larger bands. The functional significance of band formation is not yet fully understood, but it could offer individuals better protection from takeover attempts by bachelor males through safety-in-numbers of collective defence. This hypothesis will be explored using a playback-based field experiment.
• Angolan colobus monkeys in Rwanda live in supertroops of several hundred individuals. However, very little is known about the ecological preconditions (resource abundance and distribution) that allow these primates to live in such extremely large groups and nothing is known about how these supergroups are internally structured. Professor Grueter’s field research is designed to fill this knowledge gap.

Collaborator/s

  • Institute of Zoology, Chinese Academy of Sciences
  • Dian Fossey Gorilla Fund International, Karisoke Research Center