Why do we yawn?why do animals yawn?

Question

why?

Answer 1

I heard it's a way to get oxygen into the brain

Answer 2

to compensate oxygen depicit

Answer 3

additionally, yawning is a social signal left over from our cave days, that gets the other people yawning too, whcih is a a cue for bed time.

Answer 4

i saw your question on your cats upper lip my cat is 11 mnths and saw the same thing after she gave birth, did u find out anymore?

Answer 5

In humans, yawning is a natural response to the body not getting

enough oxygen.  When the body realizes it is not getting enough

oxygen, it will force a yawn to make you breathe deeply and get more

air into the lungs.

It would seem obvious that the same reason would apply to animals

although there have been studies that suggest that animals yawn to

clear the air from their inner ear passages much the same way we yawn

on an airplane to make our "ears pop."