PH
Yawning is one of those physical actions it seems impossible to escape. In addition, anyone who has been in the presence of someone else who is yawning can attest to a simple fact: it’s contagious. Given how common yawning is and how quickly it seems to spread, it is all the more remarkable to discover how little science actually knows about it.
Prevailing wisdom suggests the process is the body’s way of getting more oxygen-rich blood to the brain, since it seems possible humans take fewer deep breaths when they are tired. However, the actual neurology behind the need for this particular process is still somewhat lacking. Many other animals yawn as well, however. The contagiousness of yawning may stem from social mirroring, which is the process by which animals mimic the behavior of others, particularly those actions that might seem to be beneficial.
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