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Chimpanzees have policemen, too


Conflict management is crucial for social group cohesion, and while humans may still be working out some of the details, new research shows that some chimpanzees engage in impartial, third-party "policing" activity as well.

The full results are published Mar. 7 in the open access journal PLoS ONE. Anthropologists from the University of Zurich, led by Prof. Carel van Schaik and Claudia Rudolf von Rohr, reveal that chimpanzees mediate conflicts between other group members not for their own direct benefit, but to preserve the peace within the group. The authors suggest that this behavior can be regarded as an early evolutionary form of morality.

Until now, this morally motivated behavior in chimpanzees was only ever documented anecdotally. However, the new study now confirms that chimpanzees intervene impartially in a conflict to guarantee the stability of their group, exhibiting prosocial behavior based on an interest in community concern.

This policing activity was rare and generally limited to high-ranking individuals. The researchers also found that the arbiters were more willing to intervene impartially if several quarrelers were involved in a dispute, probably because such conflicts are more likely to jeopardize group peace.

"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.


Citation: von Rohr CR, Koski SE, Burkart JM, Caws C, Fraser ON, et al. (2012) Impartial Third-Party Interventions in Captive Chimpanzees: A Reflection of Community Concern. PLoS ONE 7(3): e32494. doi:10.1371/journal.pone.0032494

Financial Disclosure: This study was funded by the University Priority Research Program in Ethics at the University of Zurich and the A. H. Schultz-Foundation of the Anthropological Institute and Museum at the University of Zurich as well as the Liverpool John Moore University and the Chester Zoo, both in the UK.

Furthermore, the authors thank the Lucie Burgers Foundation in the Netherlands for funding data collection in Arnhem. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing Interest Statement: The authors have declared that no competing interests exist.


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