Dogs yawn along with their owners, according to researchers reporting in the journal PLOS ONE. Teresa Romero and her colleagues from the University of Tokyo discovered that dogs yawn when they watch a person yawning, and respond more frequently to their owner’s yawns than to a stranger’s yawns.

“The present study aims to replicate contagious yawning in dogs and to discriminate between the two possible mediating mechanisms (i.e., empathic vs. distress related response),” the researchers wrote in the study’s abstract.

In the study, the researchers had dogs observe their owner or a stranger yawn, or imitate a yawning mouth motion. They found that dogs yawned considerably more after their owners’ actions than to the strangers’ yawns. They also noted that the dogs responded less frequently to the fake yawns, revealing that they have the capability to yawn in response to other people yawning.

Previous studies have revealed that dogs yawn in response to humans yawns, but scientists didn’t known whether this was a mild stress reaction or an empathetic response.

“The evidence supporting the link between contagious yawning and empathy is not specific to humans. Chimpanzees (Pan troglodytes), bonobos (Pan paniscus) and gelada baboons (Theropithecus gelada) have been reported to yawn contagiously when they observe a conspecific yawning,” the researchers added.

The study’s findings suggest that the empathy scenario is true, because dogs reacted more to their owners’ real yawns than those of a stranger. The researchers detected no major variations in the dogs’ heartbeats during the tests, suggesting that it is not probable that their yawns were a mild stress reaction.

“Our study suggests that contagious yawning in dogs is emotionally connected in a way similar to humans. Although our study cannot determine the exact underlying mechanism operative in dogs, the subjects’ physiological measures taken during the study allowed us to counter the alternative hypothesis of yawning as a distress response,” Romero said in a news release.