Glancing around, you’ll notice that not only people yawn. This habit is characteristic of many mammals, birds and even reptiles. However, the true reason of yawning is still not known. So, today I’ve got some interesting hypotheses. Choose the one you like best!
Why do we yawn?
When there’s not enough oxygen
According to one of the most popular theories, yawning is a respiratory reflex, which regulates the level of oxygen in our blood. In other words, fatigue, boredom or staying in a stuffy smoke-filled room starts to slow down our breathing and this causes that less oxygen enters our lungs. So, as soon as blood accumulates excess carbon dioxide, the brain gives our lungs a signal: “Take a deep breath,” and we start yawning.
Protection against overheating
Some scientists disagree with the previous hypothesis suggesting that yawning is a way of cooling the brain. The experiment was conducted with two groups of people: one group put on their heads warm towels, the other – cold ones. The results showed that those who were with warm towels, yawned more frequently.
Regulates the pressure in our ears
Another suggestion: yawning helps to regulate the pressure in our ears. It may be when the external pressure changes (like when you fly in a plane). Since the middle ear cavity is connected to the pharynx, so when yawning this passage opens, ventilating the middle ear and equalizing the pressure.
So, if you’re constantly yawning then remember these reasons, perhaps you will need to breathe in some fresh air or there’s too hot in the room. Yawning can be a sign that your body needs some change.
Interesting fact: Yawning is contagious! That is, the innocent yawning may trigger a chain reaction of deep breaths with wide open mouths. Try to conduct a little experiment: when sitting in a meeting try to yawn. And watch how many people will follow your example.
Have you got any thoughts concerning the topic? Leave your them in the comments below…