Why is Yawning Contagious

Yawning is a natural process which we all experience thousands of times in our lives. Although there is hardly any need for a definition of yawning; in its simplest terms, it can be defined as the wide opening of the mouth due to lack of oxygen, tiredness, or sheer boredom. A lot of air is inhaled involuntarily when a person yawns and an average yawn lasts for 5-6 seconds. Yawning is an involuntary action and is acquired by man since birth. It is also believed that a baby starts yawning while still in the womb. Apart from human beings, animals like the jaguar, monkey, gull, hippopotamus, parrot, etc. also yawn.

One must have often heard that yawning is contagious. Is it so? It is observed that babies and infants (under 4 years of age) do not respond to yawning, if anyone around them yawns. On the other hand, yawning is very contagious in adults. Adults tend to yawn when they see others yawning, when they read about yawn in a book, or even when they hear a yawn on the telephone. This is true even in cases of deaf and blind people. Peculiarly it is also seen that autistic and schizophrenic people are not contagious to yawning. Peculiarly, yawning is also contagious in case of animals. But, it is not observed or proven whether yawning is contagious form humans to animals, or vice versa.

Why Do We Yawn?
There must have been several occasions when you must have observed that when a single person in a group yawns, the others suddenly get an irresistible urge to yawn. People may try to stifle the yawn, but, the urge that makes them yawn is unconscious. There are a few theories that help in understanding why yawning is contagious. As mentioned above, it is found that people yawn because of lack of oxygen. Therefore, when in a crowd, many people yawn in order to inhale more oxygen. This is considered as one of the most common reasons why people yawn when in larger groups. However, it is harder to prove that this is the reason for yawning to be contagious.

Some researchers also believe that the yawning in a group dates back to the ancient times when stone age men used to yawn together in order to intimidate other by showing their teeth. On the other hand, some researchers also believe as yawning is a sign of tiredness and boredom, people in ancient times would yawn when in a group to signal each other that it was time to retire or sleep. In ancient times, the people who yawned were considered less energetic and hence were protected and sheltered by others. They were even not allowed to get into danger.

Some scientists believe that yawning is based on the reaction of certain processes in our brain. They found that there is a tiny part in the brain which controls all the facial expression of the human beings. Therefore it is believed that when a person sees another person yawning, this part becomes active and responds in the similar way. This entire process in unconscious. On the other hand, strangely, contagious yawning is also considered to be a form of showing empathy or belongingness. None of these theories are proven yet.

Yawning is definitely contagious. However, although there have been several researches and surveys undertaken to prove it, there has not been any satisfactory reason discovered.