If you're showing signs of sleepiness, your pooch might do the same. It's already been suggested that yawning is contagious between dogs and humans, but researchers in Japan have taken things further: They've found that your dog is more likely to "catch" your yawn than a stranger's, HealthDay reports. The scientists investigated 25 canine subjects of various breeds. "Our results show that the emotional bond between people and their dogs is reciprocal," says a researcher.
Dogs are thought to yawn when they're stressed, NBC News notes. But the researchers tracked their heart rates during the experiment and found them to be steady, suggesting these were empathetic, not stressed-out, yawns. Contagious yawns have previously been linked to empathy among humans: Those who score high on empathy tests appear more likely to engage in shared yawning, HealthDay points out. Only a few other species, like chimps and bonobos, seem to "catch" yawns, too. (Click for video evidence of a different kind of human-dog connection.)