Yawning happens to all of us, or to use the medical term: we all oscitate. Oscitating is a fascinating physical phenomenon that has confused and bewildered people since the first mouth opened without the intention to speak. Below are seven of our favourite fun facts about this gaping habit.

We yawn young

Doctor Robert Provine, a developmental neuroscientist at the University of Maryland, discovered that 11-week-old foetuses yawn (Source). Despite this, contagious yawning doesn’t start until around the age of two. Why? We don’t know!

A yawn lasts 6 seconds

6 seconds seems to be the average, studies have shown that male students yawn longer and more often than female students. Is that really a surprise?

Image of a kitten yawning

Yawning cools the brain

Researchers at the University of Albany found that when you breathe through your nose, it cools the blood vessels and by extension the brain. The same study discovered we yawn more in the winter months, when the air you breathe in is colder, and therefore benefits the brain’s cooling more than in the summer months (Source).

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Lower lungs love yawns

The lower lobes of our lungs are not needed when we’re resting. Exercise is when more oxygen is needed and lungs open to full capacity. Yawning allows air into the lower lungs to keep them healthy when we’ve rested a long time. This could be linked to the fact that yawning increases with boredom.

Dogs yawn with you

Research has shown that yawning is more contagious among close friends and family, however it’s man’s best friend that shares this mouth opening act more. A study by the University of Porto in Portugal found that a dog even just hearing their owners yawn sets them off – suggesting that yawn is directly linked to empathy. The study also found that dogs are 5 times more likely to yawn just after their owner than just after hearing a ‘control’ yawn.

Image of a puppy yawning

People yawn with you

Back to Dr Provine, his study found that when showing a group of adults videos of people yawning, around 50 percent of people also began yawning (Source). Similar to laughing, the contagion effect of yawning is widespread and shows empathy between fellow humans.

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No one can agree why we yawn

At the end of the day, after all the research, we are still none the wiser as to why we yawn. Even if we could figure out why we yawn, the next question is why yawning is contagious. Particularly, why are yawns contagious in humans, gelada baboons, stump-tail macaques and chimpanzees?

I yawned 43 times while researching this article. What are your yawning stories? Please share in the comments below.