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Thursday, 14 March 2019

Iconoclast v. gatekeeper?

Bullet Points for Jerry Coyne
Michael Behe


As noted here earlier, University of Chicago evolutionary biologist Jerry Coyne reviewed Darwin Devolves for this past Sunday’s  Washington Post.  As you might expect, it’s written in the venerable style of Richard Dawkins’s review of The Edge of Evolution for the New York Times back in 2007: long on sneering, smearing, and assertion; short to nonexistent on telling readers what the book’s actual arguments are. Alas, Coyne’s piece has too little intellectual content to sustain any real engagement. So I’ll simply proceed from its beginning to its end, with lines from his review in bullet points and italics. My comments follow directly after each. 

“intelligent design” arose after opponents of evolution repeatedly failed on First Amendment grounds to get Bible-based creationism taught in the public schools. … : intelligent design, which scientists have dubbed “creationism in a cheap tuxedo.”

Good idea — let’s link the author to a scorned group right at the start and smear his motives.

Milk that Epithet

Behe does not rely on the Bible as a science textbook. Rather, he admits that evolution occurs by natural selection sifting new mutations and that all species are related via common ancestors.

But we’ll call him a “creationist” anyway, to milk that epithet for all it’s worth.

Scientists … pointed out numerous scenarios in which a system fitting Behe’s definition of “irreducible complexity” could evolve in a step-by-step manner (one is the hormone pathway studied by my Chicago colleague Joe Thornton).

I showed in the Appendix that no evidence beyond handwaving has been published since Darwin’s Black Box. Again, not even a mention by Coyne that I dispute his claim.

Jerry Coyne, Theologian

these systems … embody an absurd, Rube Goldberg-like complexity that makes no sense as the handiwork of an engineer but makes perfect sense as a product of a long and unguided historical process.

Wow, the great theologian Jerry Coyne has determined that God wouldn’t have done it that way — no need for actual evidence that Darwin’s mechanism can do the job. We all anxiously await the unveiling of Coyne’s superior designs for a clotting cascade and a flagellum.

Behe’s rationale for designed mutations is circular. He claims that biochemical pathways are designed rather than evolved because they’re based on the “purposeful arrangement of parts.” But which arrangements are those designed with a purpose? They’re simply the pathways that Behe sees as too complex to have evolved.
    So Coyne can’t think of a purpose for an eye? Or for the leg gears of the planthopper? Or for the supercharged flagellum of the magnetotatic bacterium MO-1? That’s funny — the authors of the science papers on those systems that I cite in the book seem to have had no trouble identifying their purpose.

Perhaps Behe’s most ludicrous claim is this: Evolution within the lowest levels of biological classification — genera and species — might be purely Darwinian, but the origin of higher level groups — families, orders and so on — requires designed mutations. Yet as every biologist knows, groupings above the level of species are purely subjective.
                 Can Coyne tell the difference between a plant and an animal? Between a bird and a fish? A cat and a dog? Sure, as I discuss in the book, a classification system is a human invention and so it inevitably has uncertainties, ambiguities, and mistakes. But implying that biological classification reflects nothing real is disingenuous at best.
                     Behe selectively gives a handful of examples in which mutations have produced broken genes that are nevertheless useful, but he simply ignores the large number of adaptive mutations that do not inactivate genes. These include duplications, in which a gene is accidentally copied twice, with the copies diverging in useful ways (this is how primates acquired our three-color vision, as well as different forms of hemoglobin).
                          
I wrote a section in Chapter 8 titled “Evolution by Gene Duplication Revisited” in which I explain why duplication and diversification by Darwinian processes may account for some things but not for others. I specifically explain why I changed my mind about sophisticated hemoglobin, which would require much more modification starting from a simple myoglobin-like gene than would mere duplication of opsin (color-vision) genes. Coyne doesn’t even let readers know I discuss it.

Separating What from How

Behe also argues that evolution is self-limiting because natural selection “adjust[s] a biological system to its current function” and thus “works to block the system from taking up a significantly different function.” But … Think of how feathers, which probably evolved to conserve body heat in dinosaurs, opened up the possibility of flight — leading to all the diverse birds on Earth.
              It never ceases to amaze me that Darwinists like Coyne are unable to separate the question of what happened from the question of how it happened. Okay, flightless dinosaurs had feathers and birds can now fly. So what exactly is the evidence that it happened by a Darwinian process? What is the evidence that a Darwinian process could even, say, differentiate owls and crows from a common ancestor? I argue at length in the book that unintelligent processes aren’t remotely up to those tasks. Without any substantive counter-argument, Coyne simply responds like a kid on a playground: “Yes they can too do that!”

A Terrible Thing to Waste

Like his creationist kin, Behe devotes his time not to giving evidence for intelligent design but to attacking evolutionary biology.

Gee, Coyne must have missed Chapter 10 in Darwin Devolves, “A Terrible Thing to Waste,” as well as Chapters 8 and 9 in Darwin’s Black Box (“Intelligent Design” and “Questions About Design”) and Chapter 11 in The Edge of Evolution (“All the World’s a Stage”). I explain at length in those chapters and elsewhere that the work of a mind — design — is evinced precisely by the purposeful arrangement of parts, such as is found in abundance in life. For pretty much the entirety of recorded history until Darwin almost everyone thought life was designed exactly for that reason — the arrangement of parts for a purpose — as I discuss in the Preface to the book. Contrary to Coyne, it is Darwin’s audacious assertion — that complex interactive functional structures could be produced by random variation and natural selection — that has gone unsupported by pertinent evidence. Coyne’s unwillingness or inability to grasp the argument for design does not mean the argument hasn’t been made.

Since humans are placed in the same family as other great apes (Hominidae), Behe’s theory predicts that we arose without a designer’s intervention. But here he backpedals, asserting that there are “excellent reasons to suspect those differences [between humans and other apes] are well beyond Darwinian processes.” Sadly, he doesn’t give these reasons, but I’d guess they stem from the Christian belief that Homo sapiens is a special creation of God.

Actually, they stem from our personal awareness that we can reason, speak, think abstractly, and so on — in other words, that we have minds — which arguably is the most profound attribute in the world. By the way, I also wrote in the book that there are good reasons to doubt that giraffes could arise from a shorter-necked relative like the okapi, even though they are in the same biological family. For some reason Coyne doesn’t ascribe my skepticism there to Christian belief.

A Horrible Threat

In 1998, the Discovery Institute drafted the “Wedge Document,” a secret plan (leaked in 1999) to spread Christianity in America by teaching intelligent design and fighting materialism. … Well, now it’s 20 years on, and despite the efforts of Behe and other neo-creationists, intelligent design has been discredited as science and outed as disguised religion.

Yes, the horrible threat of a group trying to persuade people of its ideas by writing books and articles has so far been countered by brave folks like Jerry Coyne, who use the kind of overwhelming evidence and impeccable logic showcased in his book review.

Coyne is quite the prominent evolutionary biologist, and has been antagonistic to intelligent design arguments for decades. If Darwin’s theory were actually the powerful idea it’s claimed to be, Coyne should have been able to counter design easily, simply by summarizing its arguments and showing how Darwin deals with them. Yet he can’t even bring himself to mention what those arguments are. Instead he tries to whip up hysteria against a book that argues for what most people already believe. That speaks volumes about the actual strength of Darwin’s theory.

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