Chimps show fairness is evolutionary
Scientists have found that chimpanzees possess a sense of fairness similar to humans, proving that sharing may be evolutionary.
The chimps were tested using a modified version of a traditional game used in economics, which involves two people deciding how to divide a sum of money, but instead, two chimps were asked to divide banana slices.
By using the ultimatum game, scientists were able to see if chimps chose fairness over economics most of the time, as already proved in humans.
Three pairs of chimps participated in the game, and the results showed that they had a tendency to offer equal shares of a reward to their partner.
Another experiment showed that children, too, showed the same tendencies, which scientists said helps further explain the evolution of sharing.
Darby Proctor, who lead the scientists at Yerkes National Primate Research Centre in the US, said: "What we're trying to get at is the evolutionary route of why humans share.
"Both chimps and people are hugely cooperative; they engage in cooperative hunting, they share food, they care for each other's offspring. So it is likely that this [fairness] was needed in the evolution of cooperation.
"It seems to me that the human sense of fairness has been around in primates for at least as long as humans and chimps have been separated."
The study has been published in the Proceedings of the National Academy of Sciences.
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