If you were drawing up a guest list for an animal dinner party, sex-mad bonobos might not be your first choice, especially as they have recently been shown to cannibalise their own offspring.

But at least they will share food with strangers.

Till now it was thought that humans were the only primates to share food in this way. Chimps, for example, won’t do it. But of Duke University in Durham, North Carolina, and Suzy Kwetuenda of the Lola Ya Bonobo refuge for orphaned bonobos in the Democratic Republic of the Congo have now shows that bonobos will also “freely” share.

“It looks like bonobos share food because they like to share,” says Hare. “If you only study chimps, you only get half the picture.”

In an experiment at the bonobo orphanage, animals unlocked a door into their enclosure to let another hungry bonobo enter and share their food, even if the other ape was not a member of the same group and had not been encountered before.

Bonobos have been seen to share food in the wild, but it was not clear whether they did this only because they were being harassed or intimidated. In the experiment, however, bonobos chose to give the hungry animals access to food, which Hare says suggests an ability to act unselfishly.

The experiments were conducted before breakfast, when the apes were hungry.

Journal reference: (in press)