The Kindness of Bonobos: Why “Human Decency” isn’t Unique to Humans

Fagjun | Published 2017-11-19 21:31

Bonobos are capable of being kind to complete strangers, even when there’s no benefit to it.



Is kindness a uniquely human trait? We’re capable of doing acts of kindness, whether it be something as small as holding the elevator doors open for that harried delivery guy, or something as big as putting our own lives on the line to save someone else’s. Call it heroism, or basic human decency, but it seems as though humans aren’t the only ones in the animal world capable of kindness to strangers.


Bonobos have been found to be capable of empathy, tolerant of strangers, and even willing to share food with other bonobos that they’re not familiar with. However, researchers also wanted to know how altruistic these bonobos are--whether or not they would help a stranger in spite of there being no obvious or immediate benefit to themselves. A new study suggests that unconditional kindness seems to have evolved among our closest living ape relatives.

Sharing the Fruits of Labor

Photo via Shutterstock



While bonobos are our closest relatives, we also share over 98% of our DNA with chimpanzees, and the two Great Ape species also share close to that same amount of DNA with each other. However, the two ape species are nearly as different as night and day. Chimpanzees are known to be aggressive and prone to violence. Bonobos, however, are peaceful creatures that tend to seek out hugs when stressed. Most other animals, however, tend to go into fight-or-flight mode when placed in stressful situations.


Researchers conducted a study by first placing two bonobos that didn’t know each other in two rooms separated by a fence. The researchers then hung an apple over one room. If the bonobo in the other room climbs the fence, the apple will fall and thus be accessible to to the bonobo in the second room.


Without prompting, many of the bonobos climbed the fence to get the apple to drop into the other room. If a bonobo was placed without a partner in the room with the apple, it was less likely to make an effort to get the apple to drop. This suggested that that bonobos were motivated to help other bonobos, even when they’re strangers and there is no incentive for helping.

Contagious Yawning

Photo via Reuters/Finbarr O'Reilly



The phase of the experiment involved getting the bonobos to watch videos of other bonobos, some of whom they knew. Other bonobos in the videos were strangers to the subjects. The videos showed these bonobos either yawning or with a neutral expression. Researchers already knew that bonobos are prone to “contagious yawning”, or yawning when you see others yawning, which is a sign of empathy. The results showed that bonobos yawn when another bonobo yawns, be it a stranger or someone they know.


Chimpanzees, meanwhile, won’t react the same way. "You wouldn't be able to run this experiment with chimpanzees because they're so hostile," said Zanna Clay, a Durham University psychology professor. Chimps have to be told to help others, and they don’t exhibit empathy for chimps that don’t belong to the same group.


However, the results of the experiment show that kindness, empathy, and altruism in humans may have a biological origin. It’s possible that kindness comes to us naturally, though it doesn’t really seem that way at times.

Hey! Where are you going?? Subscribe!

Get weekly science updates in your inbox!