The question of whether yawning is contagious has not yet been sufficiently explored by scientists, but there is definitely something to it. It happened to almost everyone. Some people do not notice that their yawn might have been induced by another person’s yawning, while others are happy to experiment on this by yawning on purpose in public places and observing the chain reaction they caused.
What is yawning?
Yawning is a mostly unconscious and completely natural process. People yawn in the morning, in the evening, when they are tired or bored and when there is not enough oxygen. People have always yawned and an average person yawns several times a day, every day. It is believed that even unborn babies yawn in their mother’s uterus.
To put it simply, when a person yawns, he or she opens the mouth very wide and inhales a great amount of air, thus introducing more oxygen to the body. Oxygen provides energy to the body, which explains yawning when tired.
Yawning is not reserved to human only. Many animal species, especially mammals but also some birds, are observed yawning.
Is yawning contagious?
It is not rare for a person to yawn and trigger a response in other persons. Yawning can be contagious when a person sees another person yawn, when hears a yawn over the phone or the radio, when sees a person yawn on TV or even when a character in a book yawns. However, it is observed that yawning is not contagious for babies and infants. Some people claim that they can make their dog yawn, or that they feel an urge to yawn when their pet does so.
Given all this and observing everyday situations involving yawning, it can be concluded that yawning is, in fact, contagious. The question, though, is why.
People yawn due to lack of oxygen. This explains why in a large group of people, especially, if indoors where the oxygen supply can be limited, many of them will yawn.
Researchers have come to the conclusion that contagiousness of yawning can be explained by exploring the behavior and the habits of people in ancient times. Our predecessors used to yawn all together simultaneously to show their teeth and ward off predators and enemies. Also, people yawn when they are tired and bored so a yawn might have been a signal to retire for the day.
Some scientists believe that yawning is a process triggered by a small part in the human brain responsible for facial expression. Seeing another person yawn activates that part and triggers the same reaction. This process is, of course, unconscious.
Yawning may also be considered a sign of empathy and belonging, which is believed by some to be one of the man’s basic urges and needs.
The bottom line is that the science is yet to offer one satisfactory response as to why yawning is contagious.