An adult budgie yawning. Photo: Juniors Bildarchiv/GmbH/Alamy

Be careful not to catch that yawn. Scientists have yet to figure out what the purpose behind yawning is, but they do know that it’s contagious. They think that seeing someone else yawn causes the brain to feel some primal form of empathy, perhaps making the bystander yawn, too.

There’s anecdotal evidence that budgies—otherwise known as Budgerigars or shell parakeets—can also catch yawns from each other. Now in a paper published in Animal Cognition, researchers at the State University of New York are saying they have scientific proof.

In one experiment, the scientists put captive budgies in cages next to each other and counted the number of yawning beaks. Overall, the birds yawned three times as often as they did when they were hanging out on their own. Then, during a second experiment, the researchers showed the birds videos of other yawning budgies. This made the birds yawn twice as much as when they were left alone.

Yawning is sometimes associated with anxiety and stress in animals, so the researchers had to account for other anxiety-ridden behaviors—scratching, for example—to make sure that the budgies were actually inspiring each other, and not just freaking out. They found that these other stress-related behaviors were infrequent, and therefore, ruled out anxiety as the cause.

The scientists suggest that since the budgies were housed in the same room together, they might have some degree of social familiarity—making them more likely to yawn more. "We propose that Budgerigars represent a good model for exploring primitive forms of empathic processing," they write in the study. They also say that since there's an association between contagious yawning and empathy, there should be additional research on the behavior in other social vertebrates.

This study is the first published example of contagious yawning in non-mammals. Similar results have been seen in humans, domesticated dogs, chimps, and a particular kind of lab rat.

Here’s what a yawning budgie looks. (It sort of looks like it’s squawking, but it’s silent):

Correction: The article previously stated that the budgies in the experiment were wild. That's incorrect: The birds were purchased from commercial vendors and housed in a vivarium at SUNY Oneonta.