Blunt Talk from Four Evolutionists

 
Do you remember this cover? It caused a minor uproar a few weeks ago [see Explaining the New Scientist Cover].

Today's issue of New Scientist has a letter signed by four people who criticize the journal for its choice of cover design. It may be just about the only important thing those four have in common. There are; Daniel Dennett, Jerry Coyne, Richard Dawkins, and PZ Myers. What a motley crew! [Darwin Was Right].

What on earth were you thinking when you produced a garish cover proclaiming that "Darwin was wrong" (24 January)?

First, it's false, and second, it's inflammatory. And, as you surely know, many readers will interpret the cover not as being about Darwin, the historical figure, but about evolution.

Nothing in the article showed that the concept of the tree of life is unsound; only that it is more complicated than was realised before the advent of molecular genetics. It is still true that all of life arose from "a few forms or... one", as Darwin concluded in The Origin of Species. It is still true that it diversified by descent with modification via natural selection and other factors.

Of course there's a tree; it's just more of a banyan than an oak at its single-celled-organism base. The problem of horizontal gene-transfer in most non-bacterial species is not serious enough to obscure the branches we find by sequencing their DNA.

Darwin was wrong about a lot of things but the tree of life wasn't one of them. It's still an accurate metaphor for most of the history of life—certainly the parts Darwin wrote about.

That's not to deny the fundamentally accurate part of the inside story. At its base the tree of life looks an awful lot like a web. That's correct. It's just that it has nothing to do with Darwin. The magazine's attempt to connect modern molecular evolution with Charles Darwin was just cheap opportunism.

I can't resist noting an irony in the letter. The authors say that, "It is still true that [life] diversified by descent with modification via natural selection and other factors." The irony is that the article inside the magazine discusses molecular evolution ("molecular genetics" in their terminology). The trees derived from those studies are based almost exclusively on neutral mutations that have become fixed in species by random genetic drift. What these studies show is that life diversified by descent with modification via random genetic drift.

Even when they are writing about changes at the molecular level, some adaptationists just can't bring themselves to utter the words "random genetic drift" in public.

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