Yawning isnâ€™t a lone wolf phenomenon. New research shows that when one wolf yawns, a packmate often does too.
Watching a pack of wolves at theÂ Tama Zoological Park outside Tokyo last year,Â Japanese researchers found that the sight of a wolf yawning often triggered yawning in other wolves. And the more time the wolves spent together, the more likely it was to happen.
This is the first time this phenomenon has been observed in wolves, the researchers say.
For centuries, scientists have been puzzling over why we yawn. We tend to yawn more when weâ€™re tired than when weâ€™re not, but people and animals yawn at plenty of other times too. (How many of you have yawned so far just reading this article?) Some studies have found that yawning cools the brain, since the intake of outside air lowers internal temperature. Others say that yawning helps keep us alert, which may explain why some people yawn right before doing something stressful, like jumping out of a plane.
Still, these theories donâ€™t totally explain one of the more fascinating aspects of yawning: When we see someone else yawn, our chances of yawning go way up. The leading hypothesis among scientists, Romero says, is that this contagious yawning is related to empathyâ€”meaning an empathetic person or animal will feel tired when he or she observes another individual looking tired.
Until now, contagious yawning was thought to be something only humans and other primates like chimpanzees do. Scientists who had looked for evidence of yawn contagion among domestic dogs had gotten mixed resultsâ€”some studies seemed to show that one dog yawning triggered another dog to yawn, whereas other studies didnâ€™t find any association.