Yawn yawn yawn

Why is yawning so contagious? I have no idea, but I find it interesting that whenever one person yawns, the other follows suit. Is that person just a sheep, a copy cat or whatever... or is there an actual a scientific reason why one yawn causes a domino affect of yawns.

We all know that yawns are caused from being tired. When you see someone yawing there's that immediate empathy and self awareness, which results in you doing nothing but yawning. So with that theory I guess it's easier to catch a yawn from someone at about 2am in the morning whilst returning home from a night out and you're feeling dog tired. But can you catch yawns from children, who have different sleep patterns from adults? And on that note, most mammals yawn so why is it that we don't catch a yawn from our pets? Weird isn't it.

For a more boring explanation, yawning releases carbon dioxide that has been stored up and needs to be let out, therefore increasing your oxygen supply. But that still doesn't explain why they are so contagious.

Adelie penguins yawn as a sign of a courtship ritual. They skid off into the ice with their wide yawns, as a display of ecstatic delight from being in each others company. Interesting. I wonder if you could use that excuse on a boring date... 'oh no dear, I'm not bored, in fact I'm erotically charged from your er, intriguing train spotting stories.'

So why are yawns contagious? I guess know one knows. It shall remain one of lifes great mysteries.

But I bet that by reading this blog about yawning, that you are yawning right now.