What's the reason for Yawning?

Question

and why is it so contagious? I can make my cat yawn at will.

Answer 1

It's never been proved. It's not true that it's caused by lack of oxygen, it actually decreases more oxygen than breathing normally. It does make you more awake though.

Answer 2

It is your psyche. Auto sympathy.

Answer 3

Don't know, but did you know that Mohammed said yawning was created by Satan?

Answer 4

Yawning is a signal from one animal to another that shows it is ready to change state of mood.   For example, when the lion wakes up, it yawns, showing it is going from sleepy mood to awake, the other lions know its time to get up.   Similarly, when you yawn because you're tired, you signal to your cat, its time to sleep.  It yawns because it got the signal.  It catches through the group to let the whole group know.

You'll see athletes yawn before events, because they are changing state from calm to excited, not because they're tired.

Answer 5

The brain has a lack of oxygen.

Answer 6

no real reason, people just find you boring