Wednesday, July 16, 2008

Let's Get Rid of Darwinism

No, I am not changing my views on evolution. The title of this post is a wonderful column by Olivia Judson about why we need to stop using the term "Darwinism":

Darwin did more in one lifetime than most of us could hope to accomplish in two. But his giantism has had an odd and problematic consequence. It’s a tendency for everyone to refer back to him. “Why Darwin was wrong about X”; “Was Darwin wrong about Y?”; “What Darwin didn’t know about Z” — these are common headlines in newspapers and magazines, in both the biological and the general literature. Then there are the words: Darwinism (sometimes used with the prefix “neo”), Darwinist (ditto), Darwinian.

Why is this a problem? Because it’s all grossly misleading. It suggests that Darwin was the beginning and the end, the alpha and omega, of evolutionary biology, and that the subject hasn’t changed much in the 149 years since the publication of the “Origin.”

He wasn’t, and it has. Although several of his ideas — natural and sexual selection among them — remain cornerstones of modern evolutionary biology, the field as a whole has been transformed. If we were to go back in a time machine and fetch him to the present day, he’d find much of evolutionary biology unintelligible — at least until he’d had time to study genetics, statistics and computer science.

Oh, there would be so much to tell him! A full list would take me weeks to write out. But the obvious place to begin would be the discoveries of genetics, especially DNA. We’d have to explain that cells in each organism contain a code describing how to build that organism, written in chemical form — DNA — that evolutionary forces are constantly rewriting. Indeed, the study of DNA allows us to see the action of natural selection on a molecule-by-molecule basis. We can see the genes where natural selection acts to prevent evolutionary change, those where it drives change and those where it has no effect at all.

Then there’s the fusion of genetics with natural selection, which has enormously expanded our understanding of how natural selection can work. For example, it has led to the discovery that natural selection does not just shape individuals — the length of a beak, the color of a fin. It can also act on family groups, and thus drive the evolution of cooperation and other altruistic behaviors.

The reason is that evolutionary success can now be measured in terms of the number of genes an individual contributes to the next generation. Anyone who dies without reproducing does not directly contribute any. But because individuals have some genes in common with their family members, they can make an indirect genetic contribution if they help their relations to reproduce instead of reproducing themselves. Such “kin selection” is thought to have contributed to the evolution of the social insects — especially, ants, bees, wasps and termites — where only a few individuals reproduce and everyone else looks after the offspring.

We’d want to discuss evolution beyond natural selection — the other forces that can sometimes cause (or prevent) evolutionary change. For although natural selection is the only creative force in evolution — the only one that can produce complex structures such as wings and eyes — it is not the only force that affects which genes will spread, and which will vanish.

. . .

To return to my argument: I’d like to abolish the insidious terms Darwinism, Darwinist and Darwinian. They suggest a false narrowness to the field of modern evolutionary biology, as though it was the brainchild of a single person 150 years ago, rather than a vast, complex and evolving subject to which many other great figures have contributed. (The science would be in a sorry state if one man 150 years ago had, in fact, discovered everything there was to say.) Obsessively focusing on Darwin, perpetually asking whether he was right about this or that, implies that the discovery of something he didn’t think of or know about somehow undermines or threatens the whole enterprise of evolutionary biology today.

It does not. In the years ahead, I predict we will continue to refine our understanding of natural selection, and continue to discover new ways in which it can shape genes and genomes. Indeed, as genetic data continues to flood into the databanks, we will be able to ask questions about the detailed workings of evolution that it has not been possible to ask before.


Read it all here.

1 comment:

Gary said...

When Jesus Christ comes back to earth, Darwinism, as well as all evolutionary theory, shall be done away with.