Evolution thwarted

OK, so it seems my blogging life is governed almost entirely by articles which appear on the BBC website. But today's tale of a three-armed Chinese baby boy made me think about evolution by natural selection. This process occurs when a random mutation proves to be beneficial to an organism over a number of generations, such that the mutation gets passed on to the organisms's offspring, then their offspring, then their offspring, and so on. Eventually, a separate species is formed.

The problem with humans is that we have a very fixed idea of what is "good" and "bad" or "right" and "wrong" when it comes to our bodies. An extra arm might have proven to be of great benefit to the Chinese boy, enabling him to do things that a two-armed human could not. But medical science says it is bad, so the spare arm must be removed by surgery. This is all rather disappointing, as a chance has been missed to see what would happen if the boy was allowed to keep his extra limb. Cutting the arm off won't change his genes, I realise, so he could still end up having many armed children, but I wish they'd left it alone.

You never know. If you cut the arm off a starfish, a new one grows back. Maybe the same thing will happen to everyone's favourite tribrachial child...