Question

why a second person feel yawning when the person sitting with him yawns???

Answer 1

The answer is  Dogs demonstrate contagious yawning when exposed to human yawning. Dogs are very adept at reading human communication actions, so it is unclear if this phenomenon is rooted in evolutionary history or a result of domestication. Fish can also yawn, and they increase this behavior due to lack of oxygen.    MARK MY ANSWER AS BRAINLIEST    

Answer 2

HI

It is due to a universal phenomenon called “contagious yawning.” Catching yawns on a regular basis seems to indicate more about your personality than your sleepiness. Catching yawns may be an unconscious sign that you’re attuned to other people’s emotions, in the same way you might automatically smile or frown at someone when they do the same to you. It’s still a controversial theory, and more research is needed. There is a neurological connection—some overlap—between psychopathy and contagious yawning. Another theory claims that contagious yawning is a primitive form of unconscious communication and bonding that helped our ancestors stay safe and avoid danger long ago. Spontaneous or contagious, yawning may simply be about your brain needing to turn on its internal air conditioner. Ultimately, contagious yawning remains an unexplained mystery to scientists.

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