Dear Reader: We all yawn frequently, more often in the early morning and late evening. Does it mean we’re tired? Bored? Short on oxygen? As common as it is, we know little for certain about yawning.

Ever noticed how one yawn can trigger many? Science reveals how your brain copies others, why yawns spread so easily, and ...

Teachers might have told you off for doing it, and your parents used it to try to get you to go to bed earlier. It’s rude to do it in a meeting, and seeing someone else doing it (even if they cover ...

Seeing or hearing someone yawn can make you yawn. This phenomenon is not limited to humans; some animals experience contagious yawning, too. But why is yawning contagious? Brain cells called mirror ...

DEAR DOCTOR K: I get plenty of sleep. So why do I yawn all the time? DEAR READER: We all yawn frequently, more often in the early morning and late evening. Does it mean we're tired? Bored? Short on ...

Open your mouth wide, stretch the muscles of your jaw and upper body, take a slow breath in, and then exhale quickly. What have you done? You have yawned. Many animals, including humans, yawn. They do ...

Yawning seems like such a simple act, yet it holds surprising power over us. Just watching someone yawn — even a stranger — can suddenly trigger the irresistible urge to yawn yourself. Why does this ...

Ever catch yourself yawning just by reading about it? That’s no coincidence: yawning—stretching your jaw wide, inhaling ...