You’re sitting in the middle of class, listening to a boring discussion, and you just can’t help but yawn. A classmate who was looking at you saw you yawn, and unconsciously yawned too. Why do people yawn? And why do people yawn after seeing someone else yawn?
Yawning is an interesting behavior that is being done not only by humans, but also by animals. Most individuals assume that yawning is brought about by boredom or exhaustion. Others don’t know why they yawn, except that they see someone else yawn first, and yawn too.
Although scientists still cannot pinpoint the exact biological mechanisms of a yawn, they agree that it is an involuntary reflex that controls the oxygen and carbon dioxide levels in the blood.
What is a yawn?
Technically speaking, a yawn is a reflex wherein the individual opens his mouth and inhales deeply, followed by a slow exhalation. This is one among the many involuntary reflexes managed by the nerve and spinal centers.
Many scientists believe that the beginning of a yawn is due to fatigue or boredom. During these moments, breathing is thin and shallow, and less oxygen is brought to the lungs. When you yawn, more oxygen gets into your lungs and into your brain, making you feel more alert and energetic.
Effects of Yawning
When you yawn, the sudden rush of oxygen into your system increases your heart rate and eliminates the carbon dioxide buildup in the lungs and blood stream. Oxygen is also brought to the brain. Yawning ventilates the lungs and restores normal breathing.
Why is yawning contagious?
Scientists don’t really know why one person yawns when he sees another one yawn. And, this seemingly “contagious” behavior not only affects humans, but can be observed in animals as well. Others believe that it is because of the power of suggestion, but there’s really no exact explanation to this.
Also, another thing worth pondering on is that fetuses in the womb also yawn. Because they do not take in oxygen to their lungs until after birth, their act of yawning remains a mystery. Another thing that questions the theory of yawning is that even individuals who already have a high level of oxygen in their blood stream still yawn. If this is the case, what purpose does yawning serve?
There’s really no certain and direct answer to the reason behind yawning and why it is contagious. However, it is definitely something interesting to think about. Who knows? Maybe you’ll be the one to discover the answer to this great mystery!