Why Are Yawns Contagious?
Another popular question about yawning is, why is it contagious? Most scientists believe that yawning is contagious because it is an inherent means of communicating with others.
In ancient times when language was still in its infancy, your ancestors would use signals to communicate with one another. They would stay in large groups wherein their safety and survival depended on their capacity to communicate with each other. For instance, if danger was coming, they would bar their teeth. This meant aggression and that they were ready to put up a fight.
Yawning could have been a signal of tiredness, which would lead to a group yawn. Such an awareness of this tiredness would encourage each member to stay awake and remain vigilant in order to survive. Or, it may have simply been a sign that it was time for them all to sleep.
Another reason why yawning appears to be contagious is based on the principle of the “mirroring effect.” When you see others yawning, the mirror neurons in the brain can cause the mirroring effect and as such neurons fire up, this will lead to the yawning reaction.