Dogs Are More Likely to Yawn after Hearing the Yawn of a Familiar Human Than of an Unfamiliar Human

We know that yawning is contagious for dogs--even across species. If you yawn, a dog near you has a greater likelihood to do the same. Karine Silva's research made that determination. But her work discovered something else as well: dogs are more likely to respond to the yawn of a familiar human than a stranger. Several other primate species do, too. Which leads some researchers to speculate that yawning is a social activity that denotes empathy. Jason G. Goldman writes for Scientific American:

Indeed, humans with developmental and personality disorders that feature social deficits also show less susceptibility to the yawn contagion. In addition, contagious yawning is elicited more strongly by familiar individuals than by strangers. That’s true not just for humans, but for chimpanzees, bonobos, and gelada baboons. While contagious yawning hasn’t been studied in rats, mice, elephants, and birds, there is a link in those animals between familiarity and empathy-related behaviors as well.

 

Two other researchers, M.W. Campbell and F.B.M. de Waal, recently published their research on contagious yawning among chimpanzees and gelada baboons. They found that increased familiarity led to increased contagious yawning. And if you can increase empathy, you could work toward building a healthier society:

A principle in psychology called the “mere exposure effect” holds that exposure itself is enough to facilitate increased liking for a previously unfamiliar individual. Could that also facilitate empathy? It’s an important question to ask, because despite the fact that human culture is immeasurably more complex than chimpanzee society, the stakes are high. If nothing else, this research points out that “flexible social engagement was probably already present in the most recent common ancestor with chimpanzees,” Campbell and de Waal say.
They conclude on a hopeful note. “This flexibility opens a door to examining how we can modify who chimpanzees will form an empathy-based connection with and how strongly. Understanding this flexibility in social engagement may help explain the proximate mechanisms that allow for switching between cooperation and competition within chimpanzee and human societies.”