Scientists Binge-Watched Adorable Internet Videos to Learn Why Animals Yawn

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Photo: Farhan Hussain/Getty Images/EyeEm

There are some days where I read about a new piece of research and instantly feel a rush of envy for the scientists who were lucky enough to spend their days working on it. (Most of the time, to be perfectly honest, the study has something to do with dogs.)

And today is unquestionably one of those days: As the Washington Post reported, a team of psychologists from the State University of New York, Oneonta, have published a study in which they spent significant amounts of time watching YouTube videos of animals yawning. For science.

The study, published this week in the journal Biology Letters, found a correlation between the size of an animal’s brain and how long it yawns for. As a guideline, the study authors used a 2005 Cell paper cataloguing the average brain weights of different mammals. Focusing on 29 of those species, including humans, they scoured the internet for yawning videos and used them to calculate the average duration of each species’ yawn. The Post explained:

When the team crunched the numbers, they found that brain weight and “cortical neuron number” — the number of brain cells in the outer layer known as the cortex — were reliable predictors of yawn length, more reliable than total body size or relative brain size. Gorillas, camels, horses, lions, walruses and African elephants were all found to have shorter yawns than humans despite their massive sizes, which makes sense because their brains are smaller than ours.

In addition to providing some excellent inspiration for my own evening plans (don’t you dare judge), the study may also help scientists gain a better understanding of why animals yawn in the first place. It’s something we haven’t yet been able to answer definitively, but as the Post noted, this latest research supports the dominant theory that a yawn cools off an overworked brain: “Brains use a lot of energy, and they run hot,” the paper wrote. “Inhaling a rush of cool, ambient air chills the blood, and the widening of the jaw sends a nice blast of that breezy blood into the brain.” It makes sense, then, that bigger brains mean longer yawns — there’s more up there that needs cooling.

Just to make sure the logic holds up, though, I think I need to spend at least an hour or two looking up those videos. Call it citizen science.