The ability to choose with whom to share sensitive information is not a uniquely human trait, says Stuart Blackman.
Research shows that chimpanzees adjust the information they share about the location of hidden food according to whether they believe others are likely to take it or not.
Experiments involving bananas concealed in boxes showed that, while chimps will reveal hidden food to those likely to help them get to it, they keep it a secret from those with a history of selfishness.
Unlike human toddlers, though, they seem incapable of making the leap to actively hiding treasures from competitors.