Why do we yawn
Technically we yawn when our brains are too hot. So we yawn to cool our brains.
Because we get tired, and when we are tired we yawn
lack of oxygen
To let people know we're bored.
i think it's contagious. when some one near you yawns....kinda makes you wanna yawn too. :o
when the brain is feeling tired, it begins to yawn to take in more oxygen to keep the brain awake until the body is ready to rest
Lack of oxygen....
To let oxygen get to the brain
Because we are tired didn't get enough sleep that night and the lack of oxygen
It is the brains way to help you sleep by releasing melatonin into the brain
We yawn due to a lack of oxygen to the brain
Lack of oxygenI would open the window or exercise because our brain depends on oxygen to think
Actually scientists only speculate why we yawn...nobody actually knows the exact reason!!
Lack of oxygen