dinner with darwin

Coyne-468w

NH: What would you tell him? Steve Jones: I’d tell him that the thing that defeated him all his life, the mechanism of inheritance, had been solved and it didn’t destroy his theory – as he had thought it might – but actually supported it. He was a very rare thing, an honest scientist. Scientists are often extremely unwilling to accept that some of their ideas might be wrong and will go to any lengths to deny that possibility. But when Darwin wrote On The Origin of Species he was written to by a Scottish engineer called Fleming Jenkins with what Darwin thought was an absolutely fatal enquiry. Darwin thought that heredity worked somehow by the mixing of the averaging of the blood of the parents. In that case, Jenkins asked, if you have an advantageous character in the blood, how could you ever get it back, wouldn’t it just dilute away? Darwin immediately saw that that was fatal to his theory. He did six editions of Origin, each one worse than the one before, as he got more and more tangled up and less confident about the basic idea. But he was working with the wrong substance – blood. Inheritance is based not on liquids, as he thought, but on particles: genes. It’s a digital not an analogue system. Genetics confirms Darwin. Of course this is Mendel’s discovery, which Darwin was sent but never read.

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