You are in a waiting room with nothing but a back issue of some women’s health magazine. It’s a pretty boring place to be but you don’t have much choice. And *yawn*. You open your mouth, stretching it as wide as it can go, letting out a big yawn. And just by reading the previous sentences, you probably have yawned by now. And I tell you, as I am writing down these words, I have already yawned twice.
No, I wouldn’t want to think that my article is boring me. And moreover, I wouldn’t like to think that my writing is boring you, my readers. I have no intentions at all in making you yawn. But the thing with yawns is that, just the thought of it makes you yawn. You have probably noticed that when one person yawns, everyone else in the room yawns after. Yawning is quite contagious. It spreads like wildfire. But what causes yawning? What makes us yawn?
One thing we know for sure about yawns is that they are involuntary. Although some may argue that when they yawning can be controlled, studies show that even before we are born, we can already yawn. Fetuses as young as 11 weeks were observed to have the ability to yawn. So, yes, we have been able to yawn even before we could actually breathe in the surrounding air. But we are not so sure yet as to what cause us to yawn.
Many studies have been made regarding the mysterious act of yawning. And you would probably have observed as well that whenever you are feeling a little bored, sleepy, or just plain tired, you yawn. So, boredom causes us to yawn, as well as fatigue and drowsiness. But scientists believe that there is more to yawning than these three. Scientists and psychologists have come up with several theories for what causes us yawn.
One of the most popular theories is the physiological theory. Yawning is said to be our way of drawing in more oxygen and releasing more carbon dioxide. This also seems to prove as to why more people yawn when in groups. However, Robert Provine, a psychologist, tested this with groups of people, giving them more oxygen and less carbon dioxide. The results did not show any significant result. The number of times that the people yawned was still the same.
Another theory is the evolution theory. It is believed that our ancestors, like other animals, yawned as a form of communication. Yawning was a sign to show superiority because you show your teeth when you yawn. And through time, we have acquired it.
The truth is we don’t know for sure what causes yawning. We don’t know why we open up our mouths wide and let air gush through. Well, there are many things that we don’t know yet for sure.