We usually yawn when we feel sleepy, bored or the person around us yawns. Sometimes yawn comes for no apparent reason at all. Some people believe that yawning happens when the brain needs more oxygen. But this is far from true. According to studies, there are many theories on why do we yawn.
So what’s behind this mystery of yawning. First, let’s see what this bodily motion is: Yawning is an involuntary action that makes us open our mouth wide and breathes in deeply. It’s involuntary because we have no control over it.
Now since we know what a yawn is, let’s see what causes us to do it.
Physiological theory: Our bodies generate yawning to draw in more oxygen and remove excessive carbon dioxide. This concept explains why we yawn in groups. Larger groups produce more carbon dioxide because of which our bodies act to draw in more oxygen and get rid of carbon dioxide.
Brain-cooling theory: A more recently proposed theory is that since people yawn more in situations where their brains are a bit warmer. Tests prove that pressing hot or cold packs to their foreheads is a way to cool down their brains. But does it matter if our brain is cool or hot? Cool brains can think more clearly and hence, yawning might have developed to keep us alert.
After that you know the theories and scientific reasons behind what make us to yawn and what are the reasons behind it, you don’t have to think why we actually stretch by looking at someone yawning around you.
LEARNING BUG 