Monkeys Say, No Fair!

[jillianjiggs]

By Sharon Thompson
National Geographic Kids Magazine
Brown capuchin monkeys know when they're being shortchanged and they resent it, according to researchers at Emory University in Atlanta, Georgia.

The researchers trained capuchin monkeys to hand over small rocks in exchange for "rewards" of cucumber slices.

But when the researcher began to give some of the monkeys a tasty grape instead, the cucumber-receiving monkeys either rejected their reward or refused to trade at all. Some even threw the cucumber slices back at the researchers!

The scientists believe this is the first time a sense of fair play has been identified in a nonhuman species.