I like the theory that although we don’t know why we yawn the reason we might trigger it off in each other is that we would be in the same setting that caused the initial yawn.
BUT I have experiences which ‘disprove it’ … when I was younger I remember a cartoon/childrens movie I think called the ‘yawning man’ but could be wrong. And it half way through there is a song and all the characters start yawning.
I couldn’t help but yawn!! I even ‘tested’ it on friends and yup same effect.
It really really is socially contagious!
And its not a mimic response because its not a natural thing to do !!
Bizarre … I think we need to put our best scientists on this!
After much heavy pondering on the subject, I have come to the conclusion that yawning is caused by an imbalance in pressure between your sinus cavities and the surrounding air. When you yawn, that equalizes the the two. However, in the process it changes the outside air pressure ever-so-slightly. Of course, this means that others around you, who had formerly been standing around with equalized pressures, must now yawn to equalize their own personal air pressures. This is generally repeated continuously for the next few minutes, until everything balances out.
