Dogmatic Darwinism
The halls of academe are a long way from Dodge City's saloons, but itchy trigger fingers abound, and professors find ways to scratch the itch. No real physical fights, of course; professors prefer to duke it out in the pages of academic journals. If you're not in the line of fire, these shootouts can be entertaining. One of the more decisive ones played out recently in the pages of the journal Evolution.
The occasion was the publication of new books by Steven J. Gould and Richard Dawkins. In the public mind Gould and Dawkins are the personification of modern evolutionary theory. Through his public lectures and his monthly column in Natural History, Gould has built a retinue of admirers who enjoy his fascinating tales of nature. Dawkins's prize-winning books, with such depressing titles as The Selfish Gene and The Blind Watchmaker, have won him worldwide acclaim despite his view of life as a relentless Darwinian grind. The personalities of these prominent evolutionists do not mix. Gould's public persona is warm and fuzzy, a New Yorker who loves baseball and food. Dawkins is the apotheosis of the British intellectual snob. It's lucky that Gould teaches at Harvard and Dawkins at Oxford. One continent wouldn't be big enough for the two of them.
Besides popularizing evolution, both Dawkins and Gould have contributed new concepts to evolutionary theory. While most paleontologists were still trying to fit the reluctant fossil record into the pattern that Darwin expected-gradual change over long periods, leaving behind innumerable fossils of intermediate forms-in the early '70s Gould and Niles Eldredge proposed the idea of "punctuated equilibrium." Punctuated equilibrium simply means that the fossil record for most species doesn't change for long periods, but then changes rapidly on a geological time scale. The theory says nothing about what causes either periods of stagnation or periods of flux. Nonetheless, until Gould and Eldredge came along, most paleontologists thought the lack of change in a fossil line was uninteresting. Now it is publishable data-one half of punctuated equilibrium.
Dawkins's idea is both subtler and more conjectural than Gould's. When natural selection is at work, what does it select? The question has been debated ever since Darwin, with some evolutionists arguing for the species as a whole while others maintain that the individual organism is selected. Dawkins champions the concept that natural selection really works at the level of the gene. The stupendous progress of molecular biology in recent decades, which takes a very gene-centered view of life, has helped to sweep Dawkins's point of view into the limelight. Unlike Gould's fossils, however, Dawkins's so-called "selfish genes" are almost entirely hypothetical.
Both the Harvard and the Oxford evolutionists have woven their theories into something like philosophies of life. Dawkins's is unremittingly bleak: "The universe we observe has precisely the properties we should expect if there is at bottom no design, no purpose, no evil and no good, nothing but pointless indifference." Selfish genes somehow "want" to be replicated, but in the pursuit of that end the pain or pleasure they afford to their conscious robot-hosts happens without rhyme or reason. Gould's view is a bit more perky. Emphasizing the role of happenstance within the ivied hall of life, species rise and fall for no discernible reason-biological revolutions may succeed just by dumb luck. Occasionally Gould has publicly predicted the demise of Darwinism, to be replaced by something (to be named later) more congenial to his philosophy. Such deviance sets Darwinian teeth on edge.
Evolution invited Gould and Dawkins to review each other's books, Full House and Climbing Mount Improbable, with the reviews appearing in tandem in the same issue. In the dustup, Gould took it sharply on the chin, but landed no blows himself. Dawkins sniffed, "[Gould's] general statistical argument is correct and mildly interesting, but no more so than several other homilies of routine methodology about which one could sensibly get a bee in one's bonnet." What is more, said Dawkins, Gould's pet theory was nothing new: "The theory of punctuated equilibrium itself is gradualist (by God it had better be) in the sense in which Darwin was a gradualist-the sense in which all sane evolutionists must be gradualists, at least where complex adaptations are concerned." In fact Gould is doing harm to Darwinism: "Gould's attempt to reduce all progress to a trivial, baseball-style artifact constitutes a surprising impoverishment...of the richness of evolutionary processes."
In the first sentence of his review Gould quotes an ancient Greek poet, "The fox knows many things, but the hedgehog knows one great thing." He never gets much clearer. The columnist for Natural History has nothing of substance to say.
That's surprising. Dawkins's Climbing Mount Improbable is not a hard target to hit-and hit hard. Here's an example. In a chapter entitled "The Forty-fold Path to Enlightenment," Dawkins describes the many different types of eyes in nature, such as the camera eye of vertebrates and the compound eye of insects. Despite their differences, at the cellular level all types of eyes work in the same way-light-sensitive cells contain a stack of membranes, each with ultra-sophisticated molecular machinery to trap photons. How could natural selection have produced the molecular machinery? No problem, says Dawkins. Concerning an illustration of a light-sensitive cell, he writes:
I count ninety-one layers of membrane in this picture. The exact number is not critical...The point is that ninety-one membranes are more effective in stopping photons than ninety, ninety are more effective than eighty-nine, and so on back to one membrane, which is more effective than zero. This is the kind of thing I mean when I say that there is a smooth gradient up Mount Improbable.
One membrane, which is more effective than zero? Hmm-let's think about that. If a cell has ninety-one light-sensitive membranes, or ninety, or just one, then clearly it already has the information to make a membrane. But if a cell has zero membranes, then it does not have the information, so how is it able to construct one? Consider an analogy. Suppose there were ninety-one bacteria in a flask. The ninety-first bacterium was formed by reproductively splitting from the ninetieth, the ninetieth from the eighty-ninth, and so forth. Where did the first come from? By splitting from the zeroeth? Going from one to two of something is a mere doubling. Going from zero to one is an infinite increase. Some smooth gradient.
Does the holder of the Oxford Chair in the Public Understanding of Science not grasp such a simple logical principle? Unlikely. It's much more plausible that he glosses over the origins of new biological structures because that is precisely the point in the process of evolution at which Darwinism has little to say. As Dawkins frankly admitted in the preface to The Blind Watchmaker, "Sometimes it isn't enough to lay the evidence before the reader in a dispassionate way. You have to become an advocate and use the tricks of the advocate's trade." I suppose that zero giving rise to one is a trick of the advocate's trade.
Many more pieces of fuzzy thinking await the skeptical reviewer of Climbing Mount Improbable. Someone with the motive and expertise of Gould could obliterate it. Yet he flounders for 4000 words.
A showdown between putative opponents that fizzles can be instructive. The simple truth is that, despite a contrast in style and emphasis, despite different pet theories, when backed into a corner, Gould agrees with Dawkins. As a materialist he could hardly do otherwise. Episodes of evolution might look fast on a geological time scale, he admits, but they are slow compared with organismal generation times. Complex adaptations are built gradually, step by step. By God they had better be; otherwise they might be by God. Gould makes his agreement with Dawkins on this point explicit.
In this important battle for informing a hesitant (if not outrightly hostile) public about the claims of Darwinian evolution...I feel collegially entwined with Richard Dawkins in a common enterprise. His metaphor of the "blind watchmaker" provides a brilliant epitome of Darwin's central principle...explaining...how a process without intentionality, and working only by a "selfish" principle of reproductive success, can yield organisms of such intricate, adaptive design.
The duel turns out to be a fake: plenty of action and special effects, but in the end a sham. Punctuated or not, everyone has agreed to agree that the blind watchmaker stands behind all living reality, unconsciously building and destroying.
Well, not everyone.
Let us go directly to the question of evolution and its mechanisms. Microbiology and biochemistry have brought revolutionary insights here....It is the affair of the natural sciences to explain how the tree of life in particular continues to grow and how new branches shoot out from it. This is not a matter for faith. But we must have the audacity to say that the great projects of the living creation are not the products of chance and error....(They) point to a creating Reason and show us a creating Intelligence, and they do so more luminously and radiantly today than ever before....Human beings are not a mistake but something willed.
Thus wrote Joseph Cardinal Ratzinger in 1986 in a little book entitled In the Beginning: A Catholic Understanding of the Story of Creation and the Fall. In this short excerpt the cardinal clashes more with Dawkins than Gould ever has. While leaving the question of mechanism to science, Cardinal Ratzinger differs where it counts: The development of life was not a blind process, but an intended one. To back up his contention, he points to advances in the fundamental science of life, biochemistry. He is on very strong ground. Hard Target
If you're not in the line of fire, a shootout can be entertaining. It's a different story when you're in the crosshairs. In the summer of 1996 Free Press published my book, Darwin's Black Box: The Biochemical Challenge to Evolution, whose main point Cardinal Ratzinger anticipated ten years earlier. Modern biochemistry has indeed discovered stunning, unexpected complexity at the basis of life. We have learned the cell is literally run by molecular machines. Bacteria propel themselves through liquid with a molecular outboard motor called a 'flagellum'; molecular supplies are packed inside tiny trucks that shuttle across the cell, delivering the cargo to specialized compartments; the cell rearranges its DNA to make new antibodies to fight disease. I argued that these systems are irreducibly complex, meaning that they require a number of parts to work. Just as a mechanical mousetrap requires each of its few parts to act as a mousetrap, so too these biochemical systems require each of their parts and so are quite unlikely to have been assembled gradually, as Darwinian theory would have it. I surveyed the technical biochemical literature-journals like the Proceedings of the National Academy of Sciences and the Journal of Molecular Biology-and showed that no scientist has ever explained how such complex systems could have been put together by natural selection. Based on an examination of the way in which the parts of biochemical systems interact with each other, I argued that the systems were deliberately designed by an intelligent agent.
Not many evolutionary biologists had trouble disagreeing with that.
Darwin's Black Box has been reviewed widely. In particular, a number of prominent evolutionary biologists, strong Darwinists all, have gotten a chance to take a hammer to it in print. Perhaps the best example was a two-page, lead review in Nature, the most prominent science journal in the world. The reviewer was Jerry Coyne, a professor of evolutionary biology at the University of Chicago and, as it turns out, the book editor for Evolution who got Gould and Dawkins to review each other's books in his journal. So what does a leading Darwinist have to say when confronted with a claim that the molecular basis of life strongly indicates design? First, sling a bit of mud:
The goal of creationists has always been to replace the teaching of evolution with the narrative given in the first eleven chapters of Genesis. When the courts stymied this effort, creationists tried a new strategy: cloaking themselves in the mantle of science. This produced the oxymoronic "scientific creationism," arguing that the very facts of biology and geology show that the Earth is young, all species were created suddenly and simultaneously, and mass extinctions were caused by a great world-wide flood.
That's the opening. He closes the review by talking about Duane Gish of the young-earth Institute of Creation Research. In between those tone-setting paragraphs he admits in passing that, by the way, "Behe is a genuine scientist," that I don't believe in a young earth, and think common descent is a reasonable idea. Guilt-by-association does make a reviewer's job easier.
After more such fun, Coyne finally gets around to addressing the design argument.
The answer to Behe's argument lies in realizing that biochemical pathways...have been rigged up with pieces co-opted from other pathways....Thrombin, for example, is one of the key proteins in bloodclotting, but also acts in cell division, and is related to the digestive enzyme trypsin. Who knows which function came first?
Good question-who knows which came first? No one knows. And no one knows how one function could explain the other. It's like saying springs are found in both watches and mousetraps, so maybe one explains the other. But the question of how complex biochemical systems came together doesn't really interest Coyne.
We may forever be unable to envisage the first (biochemical) proto-pathways. It is not valid, however, to assume that, because one man cannot imagine such pathways, they could not have existed.
Coyne's apparent argument is that we don't need evidence; life simply had to have arisen by Darwinian principles.
Coyne is not alone in his inability to answer biochemical arguments for intelligent design. In the New York Times Book Review, science writer James Shreeve declares, "Mr. Behe may be right that given our current state of knowledge, good old Darwinian evolution cannot explain the origin of blood clotting or cellular transport." In National Review, microbiologist James Shapiro of the University of Chicago acknowledges, "There are no detailed Darwinian accounts for the evolution of any fundamental biochemical or cellular system, only a variety of wishful speculations." Andrew Pomiankowski, writing in New Scientist, declares "Pick up any biochemistry textbook, and you will find perhaps two or three references to evolution. Turn to one of these and you will be lucky to find anything better than 'evolution selects the fittest molecules for their biological function."'
Darwinism is dying of the same affliction that has killed other discarded theories-the progress of science itself. It seems that with each new discovery-especially discoveries about the molecular basis of life-natural selection has a new problem. But problems for Darwinism aren't coming just from new discoveries. They come from old ones, too. Faking the Facts
Perhaps you remember the drawing from your high school biology textbook. The first row shows small, curled, worm-like creatures with odd heads, all looking pretty much the same. In the second and third rows each worm gradually morphs into a separate shape: a fish, salamander, chicken, human. This is embryology, students, and you are watching the development of different vertebrates into their adult forms. The sketches were first drawn by the prominent 19th-century scientist Ernst Haeckel, a great admirer of Darwin. Haeckel showed that all vertebrates look quite similar early in development, but diverge at later stages. Haeckel's
Many high school and college biology textbooks highlight Haeckel's work because the images make a visceral impact, and because they illustrate a basic principle of the way evolution is thought to work. The textbook Molecular Biology of the Cell, authored by National Academy of Sciences president Bruce Alberts, Nobel-laureate James Watson, and several other high-powered scientists, tells us why:
Early developmental stages of animals whose adult forms appear radically different are often surprisingly similar....Such observations are not difficult to understand. Consider the process by which a new anatomical feature-say, an elongated beak-appears in the course of evolution. A random mutation occurs that changes the amino acid sequence of a protein or the timing of its synthesis and hence its biological activity. This alteration may, by chance, affect the cells responsible for the formation of the beak in such a way that they make one that is longer. But the mutation must also be compatible with the development of the rest of the organism; only then will it be propagated by natural selection. There would be little selective advantage in forming a longer beak if, in the process, the tongue was lost or the ears failed to develop. A catastrophe of this type is more likely if the mutation affects events occurring early in development than if it affects those near the end. The early cells of an embryo are like cards at the bottom of a house of cards-a great deal depends on them, and even small changes in their properties are likely to result in disaster.
Yes, evolutionary biologists know the power of Haeckel's work. The best scientists, such as Alberts and Watson, understand how tightly these facts fit into Darwin's theory. It could hardly be otherwise.
There's just one little problem: Embryos don't look like that. The drawings are fraudulent. Haeckel faked the data.
Last year, English scientist Michael Richardson, suspicious of Haeckel's drawings, assembled an international team of embryologists to try to reproduce Haeckel's work. They couldn't. Elizabeth Pennisi reported their results in Science magazine:
Not only did Haeckel add or omit features...but he also fudges the scale to exaggerate similarities among species, even when there were ten-fold differences in size. Haeckel further blurred differences by neglecting to name the species in most cases, as if one representative was accurate for an entire group of animals. In reality...even closely related embryos such as those of fish vary quite a bit in their appearance and developmental pathway.
Richardson concludes, "It looks like it's turning out to be one of the most famous fakes in biology."
In seventh grade in parochial school my wife's science class was shown Haeckel's drawings by their teacher, a Holy Cross brother. "Evolution is true," the good brother told them, "get used to it." Throughout the last century a great many students were told the same thing, and made their peace with Darwinism as best they could. The teachers are certainly not at fault; after all, if Nobelists and presidents of the National Academy of Sciences assure you that this is what the embryos look like, how can a nonscientist disagree?
Nonscientists can't disagree. But during the last century some scientists in relevant fields have suspected that Haeckel's data were fishy. In fact, in the 19th century the faculty at Haeckel's university hauled him before a committee investigating charges of fraud. Haeckel admitted that he used artistic license, and drew the figures from memory. Nonetheless, the drawings were used in later textbooks to demonstrate evolution. In the '40s, geneticist Richard Goldschmidt wrote, "Haeckel's easy hand at drawing made him improve on nature and put more into his illustrations than he saw."
Despite the open secret of Haeckel's dishonesty, few scientists cared. I debated an evolutionary biologist a few years ago and expressed anger at the fact that Haeckel's drawings, widely known in the biological community to be grossly inaccurate, were still being used in college texts to persuade students of the truth of evolution. My opponent was unperturbed, mildly noting that textbooks can take a while to catch up with scientific advances. Like a hundred years.
All of this raises a host of questions, but let's focus on two. First, now that Haeckel's fraud has been made public, what does Darwinian theory have to say about embryogenesis?
Early development can change after all? Never mind what we said about that house of cards? Suppose a scientist predicted that a supernova would appear in the skies tomorrow...or else it wouldn't. Because opposites are consistent with the prediction, it actually predicts nothing. A star can explode or not as it pleases and the prediction is unaffected. Darwinists are in the same boat. At best Darwinism can live with both conserved development of embryos and variable development, so it says nothing at all about development. That is a telling silence, however, because Darwinian evolution simply must work by modifying the development of an embryo into its adult form. If Darwinism can say nothing about how form is generated, then it says nothing about a central question of evolution.
At worst, Alberts and Watson are right that early embryogenesis can't be changed by Darwinian evolution, and Darwinism is falsified outright. These are not happy days for fans of natural selection.
A second question is, what are we to think of Alberts and Watson? It is hardly possible for a scientist to be more distinguished than they are. But there are only two possible explanations for what their textbook teaches about the significance of Haeckel's drawings: 1) they did not know the drawings were misleading, even though Goldschmidt, Richardson, and many other scientists did know; 2) they knew the drawings were misleading, but used them anyway.
Perhaps culpable ignorance is less serious than deliberate misleading. But in either case the president of the National Academy of Sciences and the Nobel laureate are exposed as clueless about how Darwinian evolution might work on embryos. And if Bruce Alberts and James Watson do not know, nobody knows.
And that is a pretty accurate general summary of science's understanding of how life got here-nobody knows. Nonetheless, although the "how" eludes us, we can still draw a firm conclusion from the intricate, interactive structures of life: "[They] point to a creating Reason and show us a creating Intelligence, and they do so more luminously and radiantly today than ever before."
Michael