Conflicts are inevitable wherever there is cohabitation. This is no different with our closest relatives, the chimpanzees. Sound conflict management is crucial for group cohesion. Individuals in chimpanzee communities also ensure that there is peace and order in their group.

This form of conflict management is called "policing" - the impartial intervention of a third party in a conflict. Until now, this morally motivated behavior in chimpanzees was only ever documented anecdotally.

However, primatologists from the University of Zurich can now confirm that chimpanzees intervene impartially in a conflict to guarantee the stability of their group. They therefore exhibit prosocial behavior based on an interest in community concern.

The more parties to a conflict there are, the more policing there is

The willingness of the arbitrators to intervene impartially is greatest if several quarrelers are involved in a dispute as such conflicts particularly jeopardize group peace.

The researchers observed and compared the behavior of four different captive chimpanzee groups. At Walter Zoo in Gossau, they encountered special circumstances: "We were lucky enough to be able to observe a group of chimpanzees into which new females had recently been introduced and in which the ranking of the males was also being redefined. The stability of the group began to waver.

This also occurs in the wild," explains Claudia Rudolf von Rohr, the lead author of the study.

High-ranking arbitrators

Not every chimpanzee makes a suitable arbitrator. It is primarily high-ranking males or females or animals that are highly respected in the group that intervene in a conflict. Otherwise, the arbitrators are unable to end the conflict successfully.

As with humans, there are also authorities among chimpanzees. "The interest in community concern that is highly developed in us humans and forms the basis for our moral behavior is deeply rooted. It can also be observed in our closest relatives," concludes Rudolf von Rohr.

Claudia Rudolf von Rohr, Sonja E. Koski, Judith M. Burkart, Clare Caws, Orlaith N. Fraser, Angela Ziltener, Carel P. van Schaik. Impartial third-party interventions in captive chimpanzees: a reflection of community concern. PLoS ONE, March 7, 2012. doi: 10.1371/journal.pone.0032494