Humans and dogs aren't the only ones that can pass along yawns. They appear to be contagious among parakeets, too.
Videos taken in 2012 of budgie flocks suggested that yawns and stretches spread among the birds. A new study now shows that when one Melopsittacus undulatus budgerigar, or budgie, yawns another in the next cage follows suit relatively soon after. Watching a video of a budgie yawning also trigged the behavior, offering evidence that it is contagious in the birds, researchers report May 27 in Animal Cognition.
Budgies are the first nonmammal species to exhibit contagious yawning in experiments and the fifth identified to date, joining chimpanzees, domesticated dogs, a type of Sprague–Dawley rat and humans.
"Yawning in response to sensing or thinking about the action in others may represent a primitive form of empathy," the researchers note. As a result, they say, budgies could be a good test animal to get at the roots of our ability to share much more than yawns.