Promoters of this doctrine have recently been urging the Ohio State School Board to adopt science standards that would require all high school graduates to memorize Darwinian theory without questioning it, and without being exposed to any of the mounting evidence against it. To help in this campaign, the promoters enlisted the support of Brown University biology professor Kenneth R. Miller, who represented them before the Board on March 11.
Miller is not a disinterested scientific expert. As the co-author of an introductory biology textbook that has been purchased for use in the Ohio public school system, he has a substantial personal stake in the controversy. In 2000, I published a book, Icons of Evolution, criticizing the way biology textbooks--including Miller’s--systematically distort the scientific evidence to provide support for Darwin’s theory. In his appearance before the Ohio State School Board, Miller attempted to respond to some of my criticisms.
In his eagerness to defend Darwinian orthodoxy, however, Miller bungled the attempt.
Here are the facts.
(1) Peppered moths
Peppered moths come in a light-gray variety and an almost-black variety. Before 1800 the light variety predominated, but during the industrial revolution the dark variety became much more common. According to theory, the shift occurred because of natural selection: Dark moths were less visible on pollution-darkened tree trunks, and thus more likely to survive bird predation. In the 1950s, British physician Bernard Kettlewell released captive moths onto nearby tree trunks and observed as birds ate the more visible ones. When he later recaptured some moths, the proportion of moths matching the color of nearby tree trunks was higher than it had been in the group he released, consistent with the theory. The camouflage-predation story became the classic example of natural selection in biology textbooks, where it is often illustrated with photographs of peppered moths resting tree trunks.
Note that the peppered moth story, even if true, would not provide support for Darwin’s theory of the origin of species. Light and dark peppered moths were present at the beginning and the end of the story, and only their proportions changed. The change tells us nothing about the origin of peppered moths, and no new species emerged.
Even the classic story of peppered moths, however, turns out to be inaccurate. In the 1960s and 1970s, it became clear that the geographical distribution of light and dark peppered moths, and the pattern of pollution-darkened tree trunks, didn’t fit the simple picture of camouflage and predation. Then in the 1980s, biologists discovered that peppered moths only rarely rest on tree trunks in the wild. Some biologists now question Kettlewell’s results and argue that the story must be re-examined. Although no one doubts that natural selection occurs, and most biologists continue to believe that it probably accounts for what happened to peppered moths, some biologists now feel that the classic camouflage-predation story is seriously flawed.
For example, University of Massachusetts biologist Theodore Sargent and his colleagues wrote in 1998 that although the classic story might be partially true “there is little persuasive evidence, in the form of rigorous and replicated observations and experiments, to support this explanation at the present time.” (Evolutionary Biology 30, 1998, p. 318) The same year, University of Chicago evolutionary biologist Jerry Coyne wrote: “From time to time, evolutionists re-examine a classic experimental study and find, to their horror, that it is flawed or downright wrong.” According to Coyne, the fact that peppered moths do not rest on tree trunks “alone invalidates Kettlewell’s release-and-recapture experiments, as moths were released by placing them directly onto tree trunks.” (Nature 396, 1998, pp. 35-36)
Despite these problems with the classic story, many biology textbooks continue to use it as an example of natural selection in action--and continue to illustrate it with photographs of peppered moths resting on tree trunks. Since peppered moths don’t normally rest on tree trunks in the wild, though, such photographs are artificially staged.
On March 11, Miller made the following statement to the Ohio State School Board: “In his book, Icons of Evolution, Jonathan Wells accused me of fraud. He said that a textbook that I had written contained faked photographs of peppered moths on tree trunks, and also that we had mistakenly cited the work that produced those photographs as demonstrations of natural selection. The reality, however, is that those photos are not faked, and that that work is an example of natural selection. . . . In his book, Dr. Wells made the claim, quote, ‘Peppered moths don’t rest on tree trunks.’ But he didn’t present any data. When you do look at the data, what you discover is that the major observations that have been made of peppered moths in the wild most frequently show that they rest on tree trunks--and therefore, that claim is incorrect. Those faked photographs aren’t faked at all; they’re real moths, on real trees, in the real positions that moths have actually been found in the wild.”
Miller is wrong. The published scientific literature is virtually unanimous in reporting that exposed tree trunks are not the natural resting-places of peppered moths in the wild. Here are some relevant quotations from that literature:
“[T]he species probably only exceptionally rests on tree trunks. . . . [Thus] it can be emphasized that the results of Kettlewell fail to demonstrate the qualitative predation of the morphs [i.e., varieties] of the Peppered Moth by birds or other predators in natural conditions.” (Kauri Mikkola, Biological Journal of the Linnean Society 21, 1984, p. 416)
“We agree with Mikkola’s critique of field experiments to estimate the relative fitness of the phenotypes of B. betularia [the scientific name for peppered moths] by using moths exposed on tree trunks. Such predation experiments must take into account the full range of the moth’s resting sites in more, or less exposed positions.” (Tony G. Liebert and Paul M. Brakefield, Biological Journal of the Linnean Society 31, 1987, p. 145)
“We are, however, convinced that exposed areas of tree trunks are not an important resting site for any form of B. betularia.” (Rory J. Howlett and Michael E. N. Majerus, Biological Journal of the Linnean Society 30, 1987, p. 40)
“[P]eppered moths do not naturally rest in exposed positions on tree trunks.” (Michael E. N. Majerus, Melanism: Evolution in Action, Oxford, 1998, p. 121)
Miller told the Ohio State School Board that I “didn’t present any data” to justify my claim that peppered moths don’t normally rest on tree trunks. Yet my book, Icons of Evolution, included all of the citations listed above--and then some. It is Miller, not I, who fails to provide data for his assertions. Perhaps he has not read the literature, and is relying instead on misinformation supplied by his colleagues. In any case, it is clear that his statements to the Ohio State School Board were false.
It is worth noting that one of Miller’s textbooks, Biology: The Living Science (Prentice Hall, 1998), is currently being used in several Ohio school districts. Like many other introductory biology textbooks, it uses artificially staged photographs of peppered moths resting on tree trunks to illustrate natural selection. (pp. 233, 235) Yet the textbook gives students no indication that the photos are staged, that peppered moths don’t normally rest on tree trunks, or that some biologists now question the classic story of bird predation. It is not only the Ohio State School Board, but also Ohio’s science students, who are being misled by Miller’s misrepresentation of the peppered moth evidence.
(2) Haeckel’s embryos
Darwin wrote in The Origin of Species: “The embryos of the most distinct species belonging to the same class are closely similar, but become, when fully developed, widely dissimilar.” Darwin considered this early embryonic similarity to be evidence that fish and humans are descended from a common ancestor. Indeed, he wrote to Asa Gray in 1860 that he considered this to be “by far the strongest single class of facts in favor of my theory.” (Francis Darwin, ed., The Life and Letters of Charles Darwin, Appleton, 1896, vol. II, p. 131) A few years later, German Darwinist Ernst Haeckel produced drawings of vertebrate embryos in which the early stages of fish, amphibians, reptiles, birds and mammals all look remarkably similar. Haeckel’s embryo drawings became a classic textbook illustration of the evidence for Darwinian evolution, and they are still found in many biology textbooks.
Haeckel’s drawings, however, were exposed as fakes by his own colleagues, and embryologists have been re-exposing them periodically for over a hundred and thirty years. In 1997, British embryologist Michael K. Richardson and his colleagues published actual photographs of vertebrate embryos showing that the ones Haeckel portrayed as similar are actually quite different from each other. In an interview in Science, Richardson said: “It looks like it’s turning out to be one of the most famous fakes in biology.” (Michael K. Richardson, et al., Anatomy and Embryology 196, 1997, pp. 91-106; Science 277, 1997, p. 1435)
In 2000, Harvard evolutionary biologist Stephen Jay Gould wrote: “We do, I think, have the right to be both astonished and ashamed by the century of mindless recycling that has led to the persistence of these drawings in a large number, if not a majority, of modern textbooks.” (Stephen Jay Gould, “Abscheulich! Atrocious!” Natural History, March, 2000, p. 45)
In my remarks to the Ohio State School Board on March 11, I did not mention peppered moths, but I did mention Haeckel’s embryos. I cited two biology textbooks currently in use in Ohio public schools, both of which include versions of Haeckel’s drawings and both of which claim that the similarities portrayed in those drawings provide evidence for Darwinian evolution. The two textbooks (with relevant page numbers) are Kenneth R. Miller & Joseph Levine, Biology: The Living Science (Prentice Hall, 1998, p. 223), and Albert Towle, Modern Biology (Holt, Rinehart & Winston, 1999, p. 291). I acknowledged that Miller had removed the drawings from the latest edition of another one of his textbooks; and I emphasized that I was not attacking him, but merely trying to show that there is a scientific controversy over the use of such illustrations. I concluded by asking: “Should teachers be permitted to tell their students about problems with the textbook evidence for evolution?”
When Miller got up to speak, he made the following statement: “He [Wells] mentioned Haeckel’s embryos. You may be interested in this. Michael Richardson’s report on Haeckel’s embryos was published in September of 1997. In December of ’97, I put accurate photographs of those embryos up on my web site, and within four months I and my publisher had re-written this page in our textbook and we put everything together and we made it right with accurate drawings and diagrams. Two and one half years later, in October of 2000, Dr. Wells publishes his book. He makes a big deal out of the supposed fraudulent drawings in textbooks, but he completely ignores that I and other publishers had made the corrections--even though he published two and a half years after we made the corrections.”
In Icons of Evolution (Regnery, 2000), I reviewed some widely used biology textbooks, one of which was the fifth edition of Biology, by Kenneth R. Miller and Joseph Levine (Prentice Hall, 2000). That textbook contains a slightly improved version of Haeckel’s drawings and repeats the claim that “many embryos are similar in appearance, especially during the early stages of development.” (p. 283) It wasn’t until the sixth edition of Biology (Prentice Hall, 2002)--a year and a half after the publication of my book--that Miller removed the drawings altogether, and replaced them with actual photographs.
Even Miller’s photographs, however, fail to solve the problem. In Icons of Evolution, I pointed out that Haeckel had not only exaggerated the similarities among the embryos he chose to portray, but also misrepresented the midpoint of development as the earliest stage. Darwin thought the best evidence for common ancestry came from similarities in the earliest stages of embryo development, but vertebrate embryos actually start out looking very different. They become somewhat similar midway through development (though not as similar as Haeckel made them appear to be), and then they diverge again as they approach hatching or birth.
Biologists have known this for over a century. British embryologist Adam Sedgwick wrote in 1894 that the claim that vertebrate embryos are most similar in their earliest stages “is not in accordance with the facts of development.” (Quarterly Journal of Microscopical Science 36, 1894, p. 35) In 1976, Dartmouth College embryologist William Ballard wrote that it is “only by semantic tricks and subjective selection of evidence,” by “bending the facts of nature,” that one can argue that the earliest stages of vertebrate embryos “are more similar than their adults.” (William Ballard, BioScience 26, 1976, pp. 36-39) And in 1987, Canadian embryologist Richard Elinson wrote that early developmental patterns in frogs, chicks and mice are “radically different.” (In Raff & Raff, eds., Development as an Evolutionary Process, Liss, 1987, p. 3)
The photos in the sixth edition of Miller’s most recent textbook, Biology (2002), though obviously more accurate than Haeckel’s faked drawings, still show embryos at the midpoint of development. The textbook fails to mention that the pictured chicken, turtle, and rat embryos look completely different in their earlier stages. In fact, it tells students: “In their early stages of development, chickens, turtles, and rats look similar, providing evidence that they shared a common ancestor.” (p. 385) This claim is false, and the photos--carefully chosen because they appear to support Darwin’s theory--represent precisely the sort of “subjective selection of evidence” that William Ballard criticized a quarter of century ago.
So the real question is not whether Miller improved on his 1998 version of Haeckel’s drawings in 2000, or replaced them with carefully selected photographs in 2002. The real question is why Miller still persists in distorting the embryological evidence--“bending the facts of nature,” in Ballard’s words--to convince students that humans and other vertebrates share a common ancestor. Once again, it is not only the Ohio State School Board, but also Ohio’s science students, who are being misled by Miller’s misrepresentations.
(3) The Cambrian explosion
Organisms in the animal kingdom are classified into various groups; these are (from smallest to largest): species, genus, family, order, class, and phylum (plural: phyla). Individuals in the same species are very similar; individuals of two species in the same genus are slightly more different; while two individuals in different phyla are very different, and are organized according to fundamentally different body plans.
According to Darwin’s theory of evolution, all animals are descended from a common ancestor in the distant past. Supposedly, a single primitive species gradually diverged into two species, then those diverged over millions of generations to the point where we now see the major differences in body plans among worms, clams, crabs, starfish and vertebrates. Yet when we look at the fossil record we see that most of these major differences were present at the earliest appearance of animal life. Darwin himself knew this, and in The Origin of Species he called it a “serious” problem for his theory.
The geologically abrupt and simultaneous appearance of most of the major groups of animals is now known as the “Cambrian explosion,” after the name of the geological period in which they first appear. Darwin thought that the Cambrian explosion might simply be an illusion caused by flaws in the fossil record, but a hundred and forty years of additional fossil collecting have dispelled this notion. Paleontologists James Valentine and Douglas Erwin wrote in 1987 that the Cambrian explosion “is real; it is too big to be masked by flaws in the fossil record.” And in 1991, Valentine and his colleagues wrote that the Cambrian explosion “was even more abrupt and extensive than previously envisioned.” (In Raff & Raff, eds., Development as an Evolutionary Process, Liss, 1987, pp. 84-85; and Evolutionary Biology 25, 1991, pp. 279-281)
In my presentation to the Ohio State School Board on March 11, I explained that the “major differences among animals are called phyla.” I also pointed out that the Cambrian explosion of the animal phyla has led some biologists to question whether Darwin’s theory of natural selection and random variation is adequate to explain these major differences. For example, McGill University (Canada) paleontologist Robert L. Carroll wrote in 2000: “The explosive evolution of phyla with diverse body plans is certainly not explicable by extrapolation from the processes and rates of evolution observed in modern species.” (Trends in Ecology and Evolution 15, 2000, pp. 27-28) I concluded by asking: “Should teachers be free to tell students that some scientists doubt whether natural selection explains the ‘diversity and unity’ [a phrase used in the proposed Ohio science standards] of all past and present life forms?”
During the question-and-answer period after the initial presentations, Miller made the following statement to the Ohio State School Board: “The picture of the Cambrian explosion that is consistently presented by the advocates of intelligent design [I was there, in part, to defend intelligent design theory as a scientific alternative to Darwinism] is that in the Cambrian period--which goes from about 565 million years to 535 million years, give or take a few--there’s the sudden emergence of all major animal body plans. . . . By saying the major animal groups, they often convey a false impression. Do you consider insects to be a major animal group? I consider them to be the major animal group. They don’t appear in the Cambrian. Neither do mammals, reptiles, amphibians, or anything that resembles a modern fish. . . . So therefore it’s phony to pretend that all major animal body plans appeared at this point.”
Of course, insects, mammals, reptiles and amphibians are not phyla. Insects are one of several classes within the arthropod phylum, while mammals, reptiles and amphibians are classes within the chordate phylum. As a biology teacher, Miller is very familiar with these distinctions. In his textbook, Biology: The Living Science (Prentice Hall, 1998)--the one currently being used in Ohio public schools--he wrote: “To survive, all animals must perform the same functions: body support and movement, feeding and digestion, respiration, excretion, internal transport, and response to the environment. But if all animals do the same things, why don’t we all look alike? Because each major group of animals evolved its own ways of performing these functions. Over evolutionary time, each phylum combined a particular type of breathing device, a certain type of body support, and its own variations on other bodily functions. The result is a unique body plan for each phylum.” (p. 445)
On the preceding page of the same textbook, Miller included a section entitled “The Cambrian Explosion.” In it, Miller wrote: “The ancestors of almost all major living animal groups appeared in the fossil record for the first time.” (p. 444)
In other words, Miller knows very well that the “major groups” of animals are the phyla, and that most of these first appeared in the Cambrian explosion. When he told the Ohio State School Board that insects are “the major animal group,” he changed the meaning of “major group” from “phylum” to something like “most widespread group.” This is equivocation--an ancient debate tactic that changes the meaning of a word midway through an argument in order to justify an invalid conclusion. But equivocation is not science; it is sophistry.
Although Miller might be able to claim ignorance in the case of peppered moths or the case of vertebrate embryos, his own textbook deprives him of that excuse in the case of the Cambrian explosion. He himself has written that most of the major groups of animals--the phyla--first appeared in the Cambrian explosion. So he clearly knew what he was doing when he resorted to equivocation to portray me as a “phony.”
THE NEED TO TEACH THE CONTROVERSY
If the Ohio State School Board had any doubts about whether students should be taught the controversy over evolution, such doubts should have been dispelled by Kenneth R. Miller’s misleading statements on March 11. If Miller is any indication, Darwinists cannot be trusted to present a truthful and balanced picture of the evidence for and against their theory.
Yet Miller and his colleagues want the Board to grant Darwinian theory a complete monopoly in the biology classroom. They want students to be required to memorize their controversial theory without being permitted to hear any criticisms, see any counter-evidence, or consider any alternatives. In other words, they want indoctrination rather than education.
As Dr. Stephen C. Meyer and I recommended to the Board on March 11, state science standards should encourage teaching the scientific controversy over Darwinian evolution. Biology students should understand the major evidence and arguments for Darwinism, but they should also know the major evidence and scientific arguments against it. Above all, teachers should be protected from intimidation or reprisal if they choose to tell students about problems with the scientific evidence, or alternative views that exist within the scientific community.
Only then will Ohio's students be assured a quality science education.