“Most of us equate yawning with being tired, but studies have found that yawning could be caused by your body trying to cool your brain,” Dr. Jen Caudle tells Yahoo Life. She describes yawning as the ...

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 ...

Why do we yawn? Yawning is a universal gesture. Everyone yawns, from babies still in their mother's womb to the elderly. However, the exact reasons for this reflex are not well understood. Is it just ...

You know the feeling. It’s getting close to bedtime, you get sleepy, and you start yawning automatically. You may even find yourself yawning in the middle of the day in a mid-day lull. These yawns ...

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 ...

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 ...

It probably comes as no surprise that yawning is contagious. If you hear or see someone else yawn, there’s a good chance that you’ll want to yawn yourself. More specifically, contagious yawning is a ...