Have you ever noticed that it's not uncommon for someone else around you to yawn when you yawn? Yawning is a involuntary action that everyone does. But why is yawning contagious?

You might think that yawning is a precursor to sleep, but research suggests otherwise. According to this BBC article, recent research indicates that yawning may be a response that is designed to keep us awake by cooling our brains.

There are several theories as to why yawning is contagious. Some theorize that contagious yawning is a subconsious herding behavior - similiar to how birds in a flock can change direction at the same time. Others theorize that contagious yawning may be a form of communication developed by early humans to indicate alertness levels.

And I always thought that we yawned because we were tired and didn't want to be at work or school... Have you ever been in an important meeting and you couldn't stop yawning, so you kept yawning repeatedly with your mouth closed? Do people notice that? I hope not.