Why we Yawn and Cover mouth
A yawning is a simultaneous process of inhaling and exhaling a force of breath through mouth. There are multiple theories behind this involuntary physical process. That is right! – you don’t know when it is going to happen. Scientist say that it happens when body needs a good amount of Oxygen and in the process releases a lot dead air. Another theory says when you get bored or tired, you tend to yawn, may be because during boredom you forget to intake enough Oxygen and body responds to that. One theory suggests that when generally in a group one person yawns the other person is also motivated to follow the process, may be due to some psychological reasons.
Why we yawn and cover mouth while yawning is simple fact that when we inhale a good amount of air with our mouth wide stretched open there are fair chances that small things such as fly, mosquitoes, insects or even pollution can go inside so we cover our mouth to stop these things going into the mouth and creating any further trouble. Moreover, it is part of one of the social manners taught during the school time as nobody wants to see how good, bad or ugly is your teeth or how dirty is your tongue.
You must have seen a few people yawning without covering their mouth and how do you feel when you take a peek into their mouth!