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Desert Diary


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The early inhabitants of the Chihuahuan Desert necessarily had to cooperate with other members of the tribe in order to survive in the harsh environment. Interestingly enough, evidence is building up that cooperation is a genetic, not cultural, trait. It appears that altruism, the ability to cooperate with others even when it doesn't seem to be in one's rational self-interest, is built in by our evolutionary past.

Some types seem clear. In kin selection, by helping relatives to survive, you help insure the passing on of your genes, because your kin share much of your genetic material. In larger groups, reciprocal altruism—helping others in expectation of receiving help at a later time—seems reasonable. On-going research suggests another mechanism, called strong reciprocity, that works toward social cohesiveness. Through the use of specially contrived games, evidence accumulates that humans have an innate tendency to punish those who cheat and reward those who cooperate. But not something new: even our distant relatives, the Capuchin Monkeys, possess a strong sense of fairness. Distribute rewards unevenly, and those cheated refuse to play.j
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Listen to the Audio (mp3 format) as recorded by KTEP, Public Radio for the Southwest.


Contributor: Arthur H. Harris, Laboratory for Environmental Biology, Centennial Museum, University of Texas at El Paso.

Desert Diary is a joint production of the Centennial Museum and KTEP National Public Radio at the University of Texas at El Paso.



Vogel, G. 2004. The evolution of the Golden Rule. Science 303:1128-1131.