Scientists already know chimpanzees are the closest human relatives. They now say chimps and humans share a trait that was thought to be exclusive to people — a sense of fairness.

U.S. researchers at Emory University had chimps play a game called “Ultimatum,” where one chimp can choose between two tokens. One token would let him share food with the group while the other would let him keep more food for himself.

The researchers say the chimps shared as much food as a group of young children performing the same experiment for stickers.

The researchers write of the experiment in the Proceedings of the National Academy of Sciences. They say the results could provide insight into how human behavior evolved.