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Jonathan Wells critiques evo-devo and his former teacher, Gerhart

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Two biologists claim to close a “major gap in Darwin’s theory” of evolution.


Darwinian evolution is widely advertised to be a fact, as firmly established as the shape of the Earth. Defenders of the theory insist that there is no scientific controversy over it, and people who question or criticize it are typically accused of being ignorant or religiously motivated. Yet every few years a book comes along—written by scientists—claiming to remedy some major flaw in evolutionary theory.

The Plausibility of Life, by Marc W. Kirschner and John C. Gerhart, is such a book. Gerhart is an eminent cell and developmental biologist, now retired after a distinguished career at the University of California at Berkeley; Kirschner—once Gerhart’s graduate student (as was I)—is an equally eminent biologist, now a department chair at Harvard University. According to the book’s jacket, the authors close “a major gap in Darwin’s theory” and thereby provide “a timely scientific rebuttal to critics of evolution who champion ‘intelligent design.'”

By acknowledging that Behe “sees the constraint in particular designs,” Kirschner and Gerhart implicitly concede Behe’s main point, which concerns only the irreducible complexity of the conserved core processes. Behe’s argument is untouched by the fact that the basic components may be wired together in a variety of ways. Yet Kirschner and Gerhart do not even attempt to explain the complexity in those components; they merely assert that intelligent design was unnecessary. “The great innovations of core processes were not magical moments of creation,” they write, “but periods of extensive modification of both protein structure and function.” Like Topsy in Uncle Tom’s Cabin, the core processes just grow’d.

Kirschner and Gerhart also criticize Phillip Johnson and me (without mentioning us by name, except in the notes). Darwin thought that “the embryos of the most distinct species belonging to the same class are closely similar, but become, when fully developed, widely dissimilar,” and that this provided “by far the strongest” evidence for his theory that all vertebrates are descended from a common ancestor. In the revised 1993 edition of Darwin On Trial, however, Johnson pointed out that Darwin was mistaken: Vertebrate embryos actually start out very dissimilar, then they become similar midway through development before diverging again. Darwinists typically dismiss this inconvenient discrepancy by arguing that early development can evolve easily. In other words, they simply assume the truth of their theory, then use it to explain why early vertebrate embryos are so different. What had been the strongest evidence for the theory turns out to be false, but the theory is taken to be true anyway and the anomalous evidence is explained away. According to Kirschner and Gerhart, this somehow transforms dissimilarities in early vertebrate embryos “from a confounding paradox of evolution to one of its strongest arguments.”

In my book Icons of Evolution, I pointed out that using structural similarity (“homology”) as evidence for Darwinian evolution is problematic. Without an unguided natural mechanism, it is impossible to establish that similarities are due to common ancestry rather than common design. Kirschner and Gerhart argue that their theory solves the problem. Maybe. Maybe not. It would help if they could provide good evidence for their theory, but the best they can do is promise us that such evidence will be forthcoming. In the meantime, they expect us to believe that “the modern molecular evidence for homology, its development, and its evolution, is unassailable.”

So what are we to make of The Plausibility of Life? Its authors claim to complete Darwin’s theory by closing its last remaining major gap, yet they concede that the completed theory has no explanation for the origin of core processes in the first cells, the first eukaryotes, the first multicellular organisms, animal body plans, or vertebrate limbs, heads and brains. There seem to be more gaps in evolutionary theory now than there were before Kirschner and Gerhart got started.

Perhaps it would be fairer to overlook the authors’ inflated rhetoric and judge them merely on the basis of their limited theory of facilitated variation. Even if we grant the existence of conserved core processes, have Kirschner and Gerhart succeeded in explaining how land vertebrates diversified into lizards, birds, mice, whales, bats, and humans? Although they assure us that evidence will be forthcoming, the mechanisms they propose—exploratory behavior, weak linkages, and compartmentalization—have never been observed to produce anything like the novelties needed by evolution. If a century of embryology has taught us anything, it is that we can fiddle with these mechanisms all we want in a mouse embryo, and there are only three possible outcomes: a normal mouse, a deformed mouse, or a dead mouse.

Despite the dubious nature of their theoretical proposal, Kirschner and Gerhart imply that anyone who continues to be skeptical of Darwinian evolution is close-minded. In particular, people who think that intelligent design might provide a better explanation for some features of living things are dismissed as ignorant, religiously motivated, and covertly seeking ways to evade the law. Like many of their fellow Darwinists, Kirschner and Gerhart ultimately resort to personal insults.

Does the theory of facilitated variation make life plausible? Not at all, since it assumes the existence of life in the first place. Does the theory of facilitated variation rebut intelligent design? Not at all, since it assumes the existence of irreducibly complex core processes in the first place. The principal take-home lesson from The Plausibility of Life is that evolutionary theory still suffers from major weaknesses, but anyone who says so without reaffirming Darwinism and condemning id is a close-minded, ignorant, Bible-thumping subverter of the Constitution.

Where’s the novelty in that?

There is something interesting in the fact that this article appears in Christianity Today. Biology and origins science are becoming hot topics of study in Christian circles. The other curious item is the number of ID proponents who find themselves publicly on the opposite sides of the ID debate with former teachers: Wells and Gerhart, Nelson and Wimsatt, Wise and Gould, Dembski and Shallit, etc.

(HT: Rob Crowther of evolutionnews.org for alerting me to the article)

Thanks Kairos for the detective work. : ) Atom
#12 In wikipedia:
Peter D. Ward is a paleontologist and professor of Biology and of Earth and Space Sciences at the University of Washington. Ward is co-author, along with Donald Brownlee, of the best-selling Rare Earth: Why Complex Life Is Uncommon in the Universe, published in 2000. In the work the authors suggest that the universe is fundamentally hostile to advanced life, and that while simple life might be abundant the likelihood of widespread lifeforms as advanced as those on Earth is marginal. Ward also specializes in the Cretaceous-Tertiary extinction and mass extinctions generally. Along with Rare Earth, he has published eight books on biodiversity and the fossil record. Ward also serves as an adjunct professor of zoology and astronomy.
So. he is mainly a paleontologist but with interests in astronomy kairos
they write. "Everything about evolution before the bacteria-like life forms is sheer conjecture." There are other major transitions in the history of life that Kirschner and Gerhart also concede remain unexplained. One of these was the "invention" of the first eukaryotes, cells with nuclei that are very different from bacteria. "Generating the first eukaryotic cell was a major and enduring accomplishment," they write. "Extensive innovation showed up in the complexity and organization of the eukaryotic ancestor." Another major transition was the origin of multicellular organisms, which require complex mechanisms for cells to aggregate and communicate with each other. Still another unexplained transition was the origin of animal body plans in the Cambrian explosion. "Once again," write Kirschner and Gerhart, "a new suite of cellular and multicellular functions emerged rather quickly and was conserved to the present." Wow, I think Kirschner and Gerhart have become my favorite accidental IDers. First they suggest that one of the three pillars of Darwinism has not been adequately addressed -- until now. They go on to state (above) that there are huge gaps in understanding, gaps way big enough to stick in a designer. Further, they seem to be suggesting that life was ingeniously engineered to be supportive of new variety. You throw in an extra limb, and the blood vessels, nerves, etc. find their own way to interface with it. They still haven't explained, of course, why pentadactylism is so tanacious. I am impressed at how they got past the censors by suggesting that their work somehow whipes out ID, when the book actually does the opposite. bFast
Well Atom, in that case it is IDers who are publicly on opposite sides of the issue with "former teachers and colleagues". For myself, in a far more minor situation, it would be Robert Ehrlich and James Trefil, both of whom debated IDers Behe and Dembski. However my relationship with these teachers was briefly through my physics courses. I admit it feels a bit uncomfortable especially because I still admire them greatly. scordova
Peter Ward (according to the linked piece by Salvador) is an astrobiologist. But yeah, maybe I just read too much into the relationship from my reading of PP. Atom
The anti-ID Ward in question, Peter Ward was indeed associated with Gonzalez. See: Chapman’s Take: A Great Night for Intelligent Design They are mentioned as colleagues, but I would welcome further info on their relationship. scordova
I was under the impression that Ward was anti-ID, maybe it’s a different Ward… They published papers together, but I thought Brownlee and Ward were teacher/mentors to Gonzalez. AFAIK Peter Ward is a paleontologist; so it seems a bit strange that Gonzales could have him as a teacher. Probably he had Brownlee. Concerning Ward's hostility to ID I think it is mainly due just to the fact that he did publish papers and a book (rare earth) which did provide scientific supports to the arguments contained in Provileged planet. So, probably Ward simply wants to avoid for himself the ID label and the related ostracism :-) kairos
I was under the impression that Ward was anti-ID, maybe it's a different Ward... They published papers together, but I thought Brownlee and Ward were teacher/mentors to Gonzalez. Please ignore my above comment if I'm in error on that point. Atom
Gonzalez and Ward
Are you sure about? I thought that they were collegues. kairos
Gonzalez and Ward Are you sure about? I thought that they were collegues.
I should also point out, regarding rapid evolution, there is also difference of opinion in the ID and creationists communities over horse evolution. Many of the creationists in the baraminology group using ANOPA analysis (ANOPA is software developed by Sternberg and Cavenaugh, and being improved by our very own johnnyb), are highly sympathetic to the idea of horse evolution. In contrast, strong doubts were cast on horse evolution in Wells book, Icons. Wells has very good points about Gerhart and Kirshner, but I would urge caution that we don't throw out all of evo-devo. scordova
I should offer that not every ID proponent is completely negative on evo-devo, Gerhart and Kirshner, and (surprisingly) perhaps not even every creationist. Our good friends at TelicThoughts (who are big advocates of Front Loaded Evolution) are favorable to Gerhart and Kirshner. There are many creationists also who are interested in a mechanism for rapid evolution. I pointed out an unsolved case of possible rapid evolution in : Marsupials and Placentals: a case of front-loaded, pre-programmed, designed evolution? scordova
As mentioned, certainly conservation and homology in design is just as powerful explanation as it is for evolutionary ancestry. Our neighbor's house and our's is most alike in the foundation, and least alike in the final trimmings. A Ford F-450 and F-550 are most alike in the chasis and engine block, and least alike in the trim and accessories. As every design engineer, manufacturing engineer, and computer programmer know, conservation of design and assembly methods is far easier and efficient. The core is typically where the greatest commanility is found, and the add-ons and "advanced" or "customized" features are where the differences generally lie. Ekstasis
I don’t know about anyone else, but posts like this are really starting to get to me. How many times are we going to read about this scientist or that one, making stuff up out of thin air and then claiming Darwinism is a sure thing, despite all the evidence? On the flip side, we see scientists who are actually following the evidence where it leads (“live mouse, deformed mouse, or dead mouse”) being labeled as religious nuts. My faith in “science” is sinking fast. I’m getting to the point where I don’t trust anything I read by “scientists”, and that makes me a nut. shaner74
Pay no attention to the elephant standing in the corner, it's not really there anyways. Please watch where you step, it's bit messy in here. mentok
Gonzalez and Ward. Atom

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