Contagious yawning

On Tuesday I was spreading the word of yawning after a member of the class yawned (only yawning out of tiredness not boredom :D) then after she yawned another member of the class yawned and another and another and another. Then a member of Shaun refused (tried to refuse to yawn) and tried fight against the yawn but like the accidental baby it just happened.
I even made a song about it, do you want to sing along with it? … deep down you want to… here it is anyway:

Imagine there's no sleeping
It's easy if you yawn
No matress below us
Above us only that boring ceiling
Imagine all the people
yawning for today...

You may say I am yawner
But I’m not the only one
Some day you will yawn with us
And the world will yawn as one

And then I thought to myself what if the world all yawned as one, we would all suffocate, the world would be full of carbon dioxide and no oxygen to be breathed, think about it … As you read this if your not in a crowded room, get that web cam on or if you don’t have a web cam go downstairs and yawn, soon you will experience contagious yawning.