Study: If it's unfair, chimps will forgive a friend
An Animal Rights Article from


January 2005

Ed. Note:  We find it very interesting that this research proved that humans and primates have many of the same emotional characteristics, yet the "scientists" fail to comprehend the primates' God given right to live free and continue to keep them captive, treating them as research objects.  We surmise that these humans don't understand fair play as well as the primates do.

Chimpanzees have a sense of fair play but how much they will tolerate depends on who they are dealing with, according to scientists.

They will put up with being short-changed if they are friends or family of the animal getting the better deal, but won't allow any monkey business if it's a stranger.

"We found variation in the response of the chimpanzees that was based on the social group they were in," said Sarah Brosnan, a researcher at the Yerkes National Primate Research Center of Emory University in Atlanta, Georgia.

"It is interesting because social psychologists have found that humans have this variability in response based on the quality of the social relationship," she added in an interview.

Brosnan and her colleague Frans de Waal first demonstrated a sense of fairness in non-humans when they showed that capuchin monkeys don't settle for any injustice at all. The capuchins did not show the same variable response as did the chimpanzees.

Their latest findings, which are reported in the Proceedings of the Royal Academy of Sciences, Series B Web site, give new clues about the role relationships play in primate and human decision-making.

It also shows the relationship response may have been around for quite a long time and could have evolved in the last common ancestor of humans and chimpanzees.

"Chimps and humans have been evolving separately for 5-7 million years but capuchins and humans have been evolving separately for about 40 million years," Brosnan said.

The scientists studied the reaction of chimpanzees to unfair situations. They observed how paired animals behaved when one was given an inferior food award for doing the same amount of work.

Chimpanzees who were in a close relationship tended to ignore the injustice. But those who knew each other less well refused to cooperate after they had been short-changed, a reaction also found in humans.

"The chimps who had lived together for their whole lives -- all but one were born and raised in the group -- did not show a response to inequity but those who were put together as adults did," said Brosnan.

The wronged chimps would either refuse to continue to work or they would not eat the food they were given.

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