Aping Empathy: Scientists Compare 'Yawn Contagion' in Humans and Bonobos

Are humans the only creatures that can feel empathy? It's a question that's still under debate. Now, though, researchers have directly compared the "yawn contagion" effect between humans and bonobos in order to compare our own empathic abilities with that of another species.

The ability to experience the emotions of others is hard to quantify in any species. This, in turn, means it's hard to measure empathy in an objective way. In humans, the transmission of a feeling from one individual to another, known as "emotional contagion," is the most basic form of empathy. Therefore, "yawn contagion," which is when you yawn when you see someone else yawn, is an example of the most pervasive forms of emotional contagion.

Humans and bonobos are the only two species where scientists have found that yawn contagion follows an empathic trend. It's more common among individuals who share a strong emotional bond, such as friends and mates. Because of this, the scientists decided to directly compare the two species.

Over five years, scientists watched both scientists and bonobos during their daily activities. They collected yawn contagion data, comparing how many times the individuals responded to others' yawns and how quickly. Surprisingly, when the yawner and responder were not friends or kin, bonobos responded just as quickly and promptly as humans. This seemed to show that the assumption that emotional contagion is more prominent in humans is not necessarily the case.

That said, humans did respond more frequently and promptly than bonobos when friends and kin were involved. Scientists believe that this may be because strong relationships in humans are built on complex and sophisticated emotional foundations linked to cognition, memory and memories.

In the end, though, the findings reveal that humans may not be the only ones to experience empathy. The study reveals that apes may also share complex social bonds that may result in empathy.

The findings are published in the journal PeerJ.