Book review: The Edge of Evolution by Michael Behe

Behe, Michael J., The Edge of Evolution: The Search for the Limits of Darwinism (New York: Free Press, 2007)

Let's be clear on some issues. If neo-Darwinian evolution (henceforth NDE) is true, that doesn't prove atheism. Francis Collins and Ken Miller are Christians. If NDE is untrue, that doesn't prove theism. David Stove was "of no religion" and David Berlinski is an agnostic. And yet it would be disingenuous in the extreme to pretend that the issues aren't related. Hence the huge quantities of mud flung in both directions on the question of origins, much of which has been copped by Prof. Behe. These controversies matter deeply.

I may link to a lot of ID sites, but, as I've said previously, I'm not committed to it very strongly if at all. I came to this book genuinely curious about what the arguments out there are. I already knew that the author supported common descent with modification, but denied that random variation + natural selection can account for that modification (the conjunction of which makes NDE). That doesn't mean he denies that RV+NS goes on, only that there's an "edge" to what it can do. He also complains by way of introduction that evidence of common descent is often paraded as evidence of the power of RV+NS, which of course it isn't. Jerry Coyne makes this exact move in his review.

The argument runs basically thus: given the rate of beneficial mutations observed in all the generations of malaria vs medicine over the last 50 years, we are not statistically entitled to expect any beneficial modifications necessitating more than 2 new protein-protein binding sites to ever occur randomly. That's because resistance to chloroquine, which requires 2 coherent point mutations, occurred only once in 10^20 parasites (I've forgotten how the link from point mutations to binding sites is made, but I don't think that's the controversial part of the book). In the vast majority of cases, the mutations that help the bloodstream resist malaria or malaria resist drugs do so by breaking rather than making cellular machinery. The same results are shown in studies involving E coli and HIV. The evidence that highly complex cellular machinery could have developed at a rate of at most two mutations at a time is nonexistent, hence it is not "biologically reasonable" to attribute said machinery to the mechanism of random variation + natural selection.

This obviously isn't a watertight proof. Maybe someday someone will be able to sketch out a pathway from zero to flagellum (say) proceeding exclusively by single or double mutations, each of which results in a survival advantage compared to that which preceeded it. Maybe they'll even be able to show that the organism could take this path without getting stuck on some intermediate fitness peak from which there's no going up without going down first. Or even if they don't, that doesn't prove such a pathway couldn't exist. Maybe, like good naturalist presuppositionalists, we should just sit tight, reassured that "science is working on it". The thing is, given that so many reviews from Darwinists seem to utterly and (surely) wilfully miss the point - Dawkins, bizarrely, goes on and on about dogs - I begin to suspect that something is rotten in the state of Denmark.

The last couple of chapters are dedicating to answering objections and attempting to explain and defend what ID is all about, making reference to fine-tuning arguments from Physics and Chemistry too. I especially enjoyed this part of the book, particularly the section dedicated to scientists caught listing all the biological discoveries they had never expected on the basis of Darwinism. So much for the complaint that ID doesn't make predictions. Behe continues to respond to objections even now on his Amazon blog.

Let's face it: a book this controversial can't fail to be worth reading, and it doesn't. Just watch out for the Great Danes.