How generous is an ape? It’s a hard question for scientists to tackle, but the answer could tell us a lot about ourselves.

People in every culture can be generous, whether they’re loaning a cellphone to an office mate or sharing an antelope haunch with a hungry family.

While it’s easy to dwell on our capacity for war and violence, scientists see our generosity as a remarkable feature of our species. “One of the things that stands out about humans is how helpful we are,” said Christopher Krupenye, a primate behavior researcher at the University of St. Andrews in Scotland.

This generosity may have been crucial to the survival of our early ancestors who lived in small bands of hunter-gatherers.

Recently, Dr. Krupenye and his colleagues tested the generosity of bonobos that live in the Lola Ya Bonobo sanctuary in the Democratic Republic of Congo.

They proved to be generous — to a point.

“It’s a really striking result,” said Felix Warneken, a University of Michigan psychologist who was not involved in the study. What makes it surprising is that in studies involving chimpanzees in the same situations, they will do the opposite.

“Chimps are really reluctant to give food away,” Dr. Warneken said.

Read the full article at The New York Times.