Scientists know that the average yawn lasts six seconds. They also know that people yawn all the time – in the morning, at bedtime, even while they are exercising. The only thing that scientists still don’t know is why we yawn in the first place.
There have been many ideas. We usually yawn more when we are bored or tired and breathing more slowly. So scientists once thought that yawning was a way to take in more air to get more oxygen to our brains. However, studies show that people still yawn even when they are breathing pure oxygen. So that idea is probably not correct.
Another idea is that yawns might move material around in our lungs so help them work better. And some experts think that yawns may be a way to give our heads and necks a good stretch.
Whatever the reason, one thing is for sure. Yawning is contagious. Remember though, yawning doesn’t necessarily mean you are bored. Just reading or talking about this topic can make you yawn. In fact, you may be yawning right now.
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"Why do people yawn?" was posted on Sunday, August 12th, 2007 at 11:35 am.
Why do I yawn all the time?
Omg I Yawned 3 Times While Reading That!!
♥