In yesterday’s Evening Standard (I do read other papers sometimes, see?), in a review by Alex Renton of Bee Wilson’s book Consider the Fork: A History of Invention in the Kitchen, I came across the following: ‘There’s the startling theory that cutlery has changed the shape of the human face, the deep overbite of the Chinese having evolved to help chopsticks into the mouth. Our overbites are smaller, because it wasn’t until 1,000 years later that we deployed knives and forks. And in some primitive societies, front teeth still meet edge to edge.’
If true, this theory certainly would be startling. It would blow Darwinian evolution out of the water. In the first place, the timescale of a thousand years doesn’t seem long enough for such a change in a human population, though of course evolutionary changes can occur rapidly with fast-breeding species like moths or bacteria. But leaving that aside, the more important problem with this theory is that there doesn’t seem to be any mechanism by which evolution could have taken place. Natural selection is not a candidate for the job here: Bee Wilson surely isn’t suggesting that Chinese people with insufficient overbite were unable to get any food into their mouths with chopsticks, and rather than use their hands the old-fashioned way simply starved to death, before they could have any offspring and pass on the no-overbite gene?
No alternative mechanism is proposed, but the theory seems to presuppose a teleological notion of evolution: an evolution with purpose, that wants to help us out. The giveaway word is to: ‘the deep overbite of the Chinese having evolved to help chopsticks into the mouth.’ Thus evolution kindly, magically arranges for the shape of the Chinese skull to change, just to make their mealtimes easier. It’s a sweet idea. But it’s a fantasy that has nothing to do with evolution by natural selection.
I haven’t read Bee Wilson’s book, only the review, so it’s possible that Renton didn’t report her views accurately. But whoever’s mistake it was, it shows the danger of using scientific terms without properly understanding them.