Humans aren't alone when it comes to yawning — all vertebrates do it too, including fish, amphibians, reptiles, birds and mammals. But why? The "evolutionarily ancient" act of yawning likely serves a ...

It happened this past week -- a yawning gap in our knowledge filled at last. Humans do it ... chimps do it ... even educated dogs do it. We all do it: We all tend to start yawning when we see, or even ...

The average adult yawns about 20 times a day. But why? Surely we can’t all be that tired. The truth is, the science behind yawning is more complex than just a few hours too little sleep. Even more ...

Confidential list of behaviors watched by TSA agents was recently leaked online. A TSA document lists exaggerated yawning as a suspicious traveler behavior. Getty Images — -- Excessive yawning, ...

The most scientifically backed theory about why we yawn is brain temperature regulation. Inhaling air can help cool brain temperature down. Even thinking about yawning can cause you to do it. It’s ...

Researchers believe the yawning robot may have triggered some biological mechanism in the chimps that they associated with sleep. Image: Popular Science composite, Getty Images/ RMJM, Aline ...

The average adult yawns 20 times per day. And when you feel a yawn coming on, it can be nearly impossible to suppress. But why does being around other yawners make you yawn? PBS NewsHour asked a ...

You know the feeling. It’s impossible to resist. You just need to yawn. A yawn consists of an extended gaping of the mouth followed by a more rapid closure. In mammals and birds, a long intake of ...

Yawning is an automatic body response to tiredness or stress. Less commonly, excessive yawning can also be a sign of an underlying health condition. It can be related to the vagus nerve, sleep ...

It is highly contagious and very common. You can catch it at any time, and there may be nothing you can do to prevent it. Sound scary? Fortunately, it, yawning, is not too harmful...unless you are on ...

Bears do it; bats do it. So do guinea pigs, dogs and humans. They all yawn. It's a common animal behavior, but one that is something of a mystery. There's still no consensus on the purpose of a yawn, ...