Why do People Yawn

Everyone, including humans and animals alike, yawn. A baby yawns, so does an old individual. A yawn is a reflex action. It causes the lungs to inhale along with simultaneous stretching of the eardrums, that is followed by exhalation. It can sometimes be a powerful non-verbal message, which often has several possible meanings associated with it, depending on the circumstances. There are many questions related to yawning like, why causes yawning, why is yawning contagious, etc. Let's see the answers to these questions.

Why do People Yawn?

Yawning is an involuntary action, which causes us to open our mouths wide and breathe in deeply. It is called an involuntary action, as we do yawn even when we are still in our mother's womb. According to some research, a fetus as young as 11 weeks old can yawn. There are a number of theories associated with what causes a yawn.

• Physiological Theory: According to this theory, our body induces yawning to draw in more oxygen into the body and remove the build-up of carbon dioxide. This is precisely the reason, why we yawn more often, when we are sitting in a large group, as a large group produces more carbon dioxide. Our bodies try to get rid of carbon dioxide, by drawing in more oxygen.
• Cooling of Brain Theory: There are some studies, which point to the fact, that yawning cools the brain, when it is overheated. The brain is able to function at its best, when it is cool and humans and other animals have evolved adaptations to accommodate this.
• Evolution Theory: There is a line of thought, according to which, our ancestors started yawning, so that the teeth could be visible and the others can be intimidated. There is an offshoot of this theory as well. According to this new theory, yawning developed from early man as a signal for us to bring about a change in activities, which are currently being carried out. If one has to talk about it evolutionarily, it was a way of maintaining vigilance or alertness.
• Boredom Theory: According to some of the dictionaries, yawning is caused due to boredom, fatigue or drowsiness. It can be taken as a sign to change the current activities.

Although, each of these theories justify, the causes of yawning, each of them do have their own loopholes.

Why do People Yawn and Why is it Contagious?

Have you ever wondered, why do you yawn, when you see someone yawning? About 55% of people yawn within five minutes of seeing someone yawn. According to some studies, which were conducted to find out, why is a yawn contagious! have concluded, that yawning is a sign of empathy. In the past, yawning was a method used for signaling each other and what we see now as a contagious reaction is actually a leftover response from human ancestors. The theory of empathy was tested out. The groups, which were tested included autistic and non-autistic children. These studies have shown that autistic children are less likely to yawn after witnessing a yawn, as compared to non-autistic children, as autistic children find it very difficult to show empathy. Although a number species of animals and fish yawn, it is seen to be contagious only in humans and other primates such as apes and chimpanzees.

Why do People Yawn, When they are Tired?

Very often, when we are tired, we notice we keep yawning all the time. Same is the case when we are under stress. It is caused as the deep brain temperature is increased, when the person is exhausted or sleep deprived. Yawning cools the brains. It can also be used as a seizure signal, at the same time excessive yawning is an indicator of brain cooling problems.

Now that you have found answers to questions related to yawning! Would you want to know some facts associated with yawning? On an average a yawn lasts approximately for six seconds and the heart rate increases by as much as 30%. Blind people yawn more, when they hear an audio tape of people yawning. Before I end this article, I want you to answer a question sincerely. How many times did you yawn, since you started reading this article on yawning?