Why Do We Yawn?

Why Is Yawning Contagious?

Have you ever wondered why when someone yawns, the other person follows suit? Yawning is caused due to low levels of oxygen in the air, which makes the body intake large amounts of oxygen. The reason why yawning is said to be contagious is because when we do so, we are actually activating our nervous system. This has something to do with the survival instinct we have inherited in the course of evolutionary past. In the primitive years, when someone would yawn, the whole group would become alert and get better at sensing danger.

What Causes Yawning?

Definition – involuntarily open one’s mouth wide and inhale deeply due to tiredness or boredom.

This is a very helpful article that dives into some of the questions and theories about yawning.

There is ongoing analysis and discussion about how yawning may serve the purpose of regulating the brain and the brain’s temperature.