Helen Fields writes in Science Now about the latest discovery from Emory’s Yerkes National Primate Research Center:
Despite our wars and crime, humans tend to be nice. We bake for our neighbors, give directions to strangers, and donate money to far-off disaster victims. But does the same go for our closest cousin, the chimpanzee? A new study suggests that it does.
People who study chimpanzees in the field have known for a long time that the apes console their comrades when they're upset and support each other in a fight. And when one chimp has a good hunting day and kills a nice, juicy monkey, it shares the meat with the other members of its group.
But scientists have found that chimps don't share in lab experiments, creating a bit of a primatology mystery. … Comparative psychologist Victoria Horner of Emory University in Atlanta thought she knew the reason why experiments didn't find sharing: the experimental setups other scientists used to test the chimps were just too confusing—"tables with pulley systems and whatnot."
With her colleagues at Emory, including renowned primatologist Frans de Waal, Horner devised a new way to test chimps' generosity. "We did the same basic idea but from a more chimpy perspective," she says.
Read the full article in Science Now.
In the experiment, chimpanzees were trained to exchange tokens for food. One color token would buy a packet of food for the chooser, while another color would buy a packet for the chooser and her partner in the experiment. The chimpanzees were more likely to pick the generous color. Illustration by Devyn Carter.