After publishing my last post I noticed I’d downloaded from somewhere (maybe the Sanford article) a 2008 paper by Austin L Hughes about the methods that are used to detect genes that have been subject to natural selection.
Hughes is a professor of biology at South Carolina University with 35 years of experience, a mass of well-cited articles to his credit and a wide range of research interests: Evolutionary Studies, Conservation Biology, Computational Biology, Vertebrate Biology, Insect Biology and BioInformatics.
The paper’s quite short, and although a little technical in the middle is well-worth reading. One of the things, in discussions on sites like BioLogos, that intimidates the non-professional who has doubts about the sufficiency of natural selection is the citing of many examples of genes that have been subject to selection. There’s clearly a tool, or tools, available to biologists-who-understand-evolution that removes all doubt about the matter. However, Hughes’s article not only casts reasoned doubt on the methods being employed for this purpose, but shows they are fallacious by a specific and clear example from the literature (the opitimisation of eye pigments). Here’s an important, and challenging, summary statement:
Contrary to a widespread impression, natural selection does not leave any unambiguous “signature” on the genome, certainly not one that is still detectable after tens or hundreds of millions of years. To biologists schooled in Neo-Darwinian thought processes, it is virtually axiomatic that any adaptive change must have been fixed as a result of natural selection. But it is important to remember that reality can be more complicated than simplistic textbook scenarios.
Hughes goes on to make the same point I raised in my post: that the evidence seems to point to nearly all biological change being, according to the evidence, due to near-neutral chance mutations not subject to positive selection. This does raise once more the spectre of a complete lapse into implausibility – if evolution by natural selection made it intellectually viable to be an atheist, neutral evolution throws one back either on many-world multiverses or miracles. And the paper makes no effort to resolve that, having demolished (once again) the foundation for Neodarwinism. It’s no wonder that, despite neutral theory’s increasing dominance, we’re always tossed the bait of Darwinian natural selection – and gradualist selection at that – to assuage any qualms we might have about getting up Mount Improbable in one piece.
But I suspect Hughes may have a more sophisticated and interesting take on these matters from another article I’ve just found by him, which is an able critique of scientism in The New Atlantis. The guy is clearly widely-read and a serious thinker – and scientists like that seem to buck the mainstream trends more, sadly, than most Christians who are scientists do, if BioLogos is any indication. I don’t propose to review this article, as it’s quite absorbing enough in itself – read it and get back to me with your thoughts.