Let’s begin by stating I hope you do start yawning as you read this. I will do my best to make it interesting. The question of why we yawn has been asked for many years and a number of theories offered up to explain it. One of the most long-lived is that it helps with our breathing. The theory goes on to say that it is a mechanism whereby more oxygen is allowed to enter your lungs whilst at the same time expelling excess carbon dioxide.
It is a neat theory but in the 1980s, scientists tested it out and found it wanting. What they did was to feed different amounts of oxygen to volunteers. The result was that there was no real difference in the amount of yawning witnessed. Another more improbable theory points to a gene which in ancient evolutionary times may have been associated with the gills of a fish. We know that we are descended from fish and that is why this theory was put forward. There is very little evidence for this.
So, do we have a better idea as to why we yawn? In fact, we do. It is now believed that yawning may help to cool our brains down. The analogy has been drawn that it is like the fan inside your computer. Some experiments tend to indicate that we yawn more when in a warm environment than when in a sold one.
There is another question often asked about yawning and that is why do we tend to yawn when we see somebody else yawning? And the other person may be a friend or a complete stranger. We do not know the answer but it has been put forward that it may be a form of ancient communication. It is supposed to signal to others that you are tired or fatigued and maybe they should also feel the same. It is thought to be a way of syncing up body clocks.
Hopefully, you are still awake and not yawning too much!
John Pullen 