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July 28, 2011
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Turkana warriors. Punishment helps sustain cooperation when fighting against other groups.
Two UCLA anthropologists analyzed warfare among a society of pastoral nomads in East Africa and found third-party sanctions for violating normative behavior helped sustain cooperation when fighting against other groups.
Credit: Dr. Chapman Family, Turkana Missionaries 1977-2005
Images credited to the National Science Foundation, a federal agency, are in the public domain. The images were created by employees of the United States Government as part of their official duties or prepared by contractors as "works for hire" for NSF. You may freely use NSF-credited images and, at your discretion, credit NSF with a "Courtesy: National Science Foundation" notation.
Additional information about general usage can be found in Conditions.
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Related story: Warfare Reveals Reasons People Cooperate