Darwin proclaimed wrong AGAIN; we fight back!

February 19, 2009 • 2:13 pm

The January 24th issue of New Scientist had a garish cover showing the tree of life, with the words “DARWIN WAS WRONG” emblazoned over it.   An editorial bemoaned the phylogenetic errors of the old man, adding a few other buzzwords as well:

A particularly pertinent example is provided in this week’s cover story – the uprooting of the tree of life which Darwin used as an organising principle and which has been a central tenet of biology ever since (see “Axing Darwin’s tree”). Most biologists now accept that the tree is not a fact of nature – it is something we impose on nature in an attempt to make the task of understanding it more tractable. Other important bits of biology – notably development, ageing and sex – are similarly turning out to be much more involved than we ever imagined. As evolutionary biologist Michael Rose at the University of California, Irvine, told us: “The complexity of biology is comparable to quantum mechanics.”

The editors knew in fact that this sensationalistic cover would be appropriated by creationists (as it indeed was), but still said that a “revolution” in biology was in the offing:

As we celebrate the 200th anniversary of Darwin’s birth, we await a third revolution that will see biology changed and strengthened. None of this should give succour to creationists, whose blinkered universe is doubtless already buzzing with the news that “New Scientist has announced Darwin was wrong”. Expect to find excerpts ripped out of context and presented as evidence that biologists are deserting the theory of evolution en masse. They are not.

What is so wrong with the tree of life?  Well,  an article by Graham Lawton asserts that horizontal gene transfer (the movement of bits of DNA between species by “infection”), a phenomenon often seen in bacteria and some protists, and occasionally in complex metazoa, invalidates the whole idea of a tree with bifurcating branches.  This, of course, is nonsense.  Such gene transfer may fuzz out or even obscure genealogies in some prokaryotes, but nobody thinks it’s going to efface the genealogy of most other groups.  Can we expect to find that we’re really more closely related to gibbons than to chimpanzees, a truth that has been obscured by massive horizontal transfer from eating bush meat?  Don’t expect huge changes in the genealogy of life that we’ve already assembled from molecular data.

And chalk up another erroneous and irresponsible journalistic asssertion that Darwinism is dead.  Several of us, including Dan Dennett, P. Z. Myers, and Richard Dawkins, wrote a letter (“Darwin was Right”)  to the editor of New Scientist. You can find it here.  An excerpt:

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. . . .

The accompanying editorial makes it clear that you knew perfectly well that your cover was handing the creationists a golden opportunity to mislead school boards, students and the general public about the status of evolutionary biology. Indeed, within hours of publication members of the Texas State Board of Education were citing the article as evidence that teachers needed to teach creationist-inspired “weaknesses of evolution”, claiming: “Darwin’s tree of life is wrong”.

“Revolutionary” sentiments are rife  in evolutionary biology, but let’s be a little careful before we throw away a paradigm which has, after all, proved to be largely correct for a century and a half.  I didn’t anticipate that Darwin Year would bring the neo-Kuhnians out of the woodwork to clamor for an Extended Evolutionary Synthesis. I still can’t see what’s wrong with the old one!