|Title||Ingroup-Outgroup Bias in Contagious Yawning by Chimpanzees Supports Link to Empathy|
|Publication Type||Journal Article|
|Year of Publication||2011|
|Authors||Campbell, MW, de Waal, FBM|
|Keywords||2011-04-14, chimpanzees, communication, sociality|
Humans favor others seen as similar to themselves (ingroup) over people seen as different (outgroup), even without explicitly stated bias. Ingroup-outgroup bias extends to involuntary responses, such as empathy for pain. However, empathy biases have not been tested in our close primate relatives. Contagious yawning has been theoretically and empirically linked to empathy. If empathy underlies contagious yawning, we predict that subjects should show an ingroup-outgroup bias by yawning more in response to watching ingroup members yawn than outgroup. Twenty-three chimpanzees (Pan troglodytes) from two separate groups watched videos of familiar and unfamiliar individuals yawning or at rest (control). The chimpanzees yawned more when watching the familiar yawns than the familiar control or the unfamiliar yawns, demonstrating an ingroup-outgroup bias in contagious yawning. These results provide further empirical support that contagious yawning is a measure of empathy, which may be useful for evolutionary biology and mental health.
Ingroup-Outgroup Bias in Contagious Yawning by Chimpanzees Supports Link to Empathy
For years, I've worked on their bones. Now I'm working on their genes. Read more about the science studying these ancient people.
From a finger bone of an ancient human came the record of a completely unexpected population. My lab is working on the science of the Denisova genome.
The advent of agriculture caused natural selection to speed up greatly in humans. We're uncovering some of the ways that populations have rapidly changed during the last 10,000 years.