due to less oxygen supply to the body
People yawn because they are bore.....right now,their is no approved causal of yawnimg
Insects do not yawn. People necessarily do not yawn only when they are tired. Most people, after reading this, will yawn.
A yawn is normally a response to a change in activity, although if you did not get enough sleep, you could become tired and yawn.
when you are tired, your breathing slows, which means less oxygen travels to your brain, thus causing you to yawn.
People yawn, because its the fastest way to send air up into your brain, so if you were tired and your not thinking well, you would most likely yawn to get your brain working better.
When I am sleepy or tired I yawn.
People don't just yawn because they're sick, first of all, they're brain sends out a message to the body, and then the body reacts as a yawn. You also yawn when you're tired, or need to lie down.
Yes when they are sleepy and tired
because your tired
because stomach aches usually make you tired by the pain so when your tired you usually yawn! does that helP?
You do not yawn when you are relaxed because scientists have proven that when you yawn, you either need sleep or it is because you are tired.
Same thing as when you yawn..... When you get tired you get a shortness of breath causing you to yawn...you yawn to catch your breath when your tired...