Saturday, December 18, 2010

Wisdom Teeth - Our Brains Squeeze Our Teeth

I asked this question few weeks ago but my dentist had no answer. Rob Dunn lists the top ten daily consequences of being evolved - here:

"Our brains squeeze our teeth
A genetic mutation in our recent ancestors caused their descendants to have roomy skulls that accommodated larger brains. This may seem like pure success—brilliance, or its antecedent anyway. But the gene that made way for a larger brain did so by diverting bone away from our jaws, which caused them to become thinner and smaller. With smaller jaws, we could not eat tough food as easily as our thicker-jawed ancestors, but we could think our way out of that problem with the use of fire and stone tools. Yet because our teeth are roughly the same size as they have long been, our shrinking jaws don’t leave enough room for them in our mouths. Our wisdom teeth need to be pulled because our brains are too big.

I have not even mentioned male nipples. I have said nothing of the blind spot in our eyes. Nor of the muscles some of use to wiggle our ears. We are full of the accumulated baggage of our idiosyncratic histories. The body is built on an old form, out of parts that once did very different things. So take a moment to pause and sit on your coccyx, the bone that was once a tail. Roll your ankles, each of which once connected a front leg to a paw. Revel not in who you are but who you were. It is, after all, amazing what evolution has made out of bits and pieces. Nor are we in any way alone or unique. Each plant, animal and fungus carries its own consequences of life's improvisational genius. So, long live the chimeras."

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