have You ever noticed that when you yawn, as all around, as if on cue, begin to do the same thing, even if no reason for yawning is not? It turns out that yawning is really contagious. Scientists have found that people unconsciously responds not only to yawn, but even on paper the word "yawn"!
The most inclined to "catch" a yawn people who have stronger capacity for empathy. People, tough in nature, and unable to imagine yourself in the other person immune to the yawn.
It is known that yawning is associated with sleepiness and often serves as a "prelude" of sleep. But this does not explain its huge infectiousness: the sleeping person does not make us yawn, nor feel sleepy.
According to one theory, the contagiousness of yawning is related to the fact that people once lived in packs, like chimpanzees, and it was important for them at the same time to go to bed. So yawning served and serves as a signal that the time has come for sleep. Sensing yawn neighbor as a signal to yawn, and then to sleep, herd animals used to sleep together, warming and protecting each other during sleep.
Contagious yawning has also been observed among animals: yawn owners contagious to dogs. No wonder: after all, dogs have an inherent ability to understand and other means of expression without words: the looks and gestures, they have a strong sense of empathy with the human host.

If you've read this article till the end and never yawned, then you should not think that you are the exception to the rule. In fact, the percentage of people who start to yawn when others do it, is from 45 to 60% (chimpanzees react to yawn only in 33% of cases, and dogs in 72%off!)
