Icons of Evolution — Science or Myth?: Why much of what we teach about evolution is wrong. Jonathan Wells. Washington, DC: Regnery Publishing. 2000. 338 + xiv pp.

When we first meet the protagonist of the film The Talented Mr. Ripley, he is playing piano at a rooftop party in New York City. As the song finishes, an older man approaches and, observing Ripley’s Princeton blazer, remarks that Ripley must have been at school with his son Dickie. Sensing an opportunity, Ripley does not mention that the blazer is borrowed from another guest, nor that he did not attend Princeton but only worked there. He merely asks, "How is Dickie?"

This kind of deception, misleading by the omission of important information, is the basis of Icons of Evolution. Its author, Jonathan Wells, appears to come from an unusually strong academic background, but the truth is more complex. Wells is a follower of the Rev. Sun Myung Moon, and explains on his website (http://www.tparents.org/library/unification/talks/wells/DARWIN.htm) that the Father instructed him to get advanced degrees in theology and biology so that he could destroy evolution. Wells wrote a theological dissertation at Yale on the "Argument to Design" and how Darwin allegedly mistook it. He then received a Ph.D. in Molecular and Cell Biology at Berkeley on the effect of gravitation on the 8-cell embryo; two multi-authored papers were produced from that lab’s work. He followed this with a 5-year "postdoc" sponsored by a retired professor in the same department at Berkeley, during which time he seems to have performed no experiments and to have received no grant support from his sponsor. He was simultaneously a "post-doc" at the anti-evolutionary Discovery Institute in Seattle, where he remains. No peer-reviewed publications proceeded from Wells’s 5-year stint, but Icons of Evolution appeared shortly after its term limit expired. Anti-evolutionists are backing him as the new "inside expert" on evolution and its iniquities. They hope that Wells’s apparent academic credentials will convince people that his arguments are legitimate. His book’s jacket features congratulatory blurbs from the likes of Phillip Johnson, Michael Behe, William Dembski, and others, without mentioning that they are all fellows of the Discovery Institute.

Wells’s thesis is that biology textbooks misrepresent classic but flawed examples (his so-called "icons") that purport to support evolutionary concepts. (Hardly news: scientists have been complaining about all kinds of textbook errors for decades. Commercial publishers, not scientists, produce what’s in textbooks.) Because these examples are wrong, Wells says, there must be no evidence for the concepts themselves. He does not attempt to find better examples, nor to show how the examples could be explained more correctly. He also does not explain that most pre-college textbooks are produced by non-scientists, and that coverage of most topics in textbooks is necessarily brief and usually simplified. His job is to sow doubt in the minds of those who do not know the examples or concepts first hand. Wells’s target audience is the anti-evolutionists, for whom he hopes to provide ammunition, and those agnostic or uninformed about evolution, who might be more antagonistic if they thought its findings were suspicious. For the benefit of these people, Wells concludes his book with an accusation of scientific fraud by evolutionary biologists and exhorts readers to complain to their congressmen so that evolutionary research won’t be funded.

Wells’s "fatal" objections are a mix of the cinematic Ripley and the one who wrote Believe it or Not!. Here we have space only to discuss three of the most egregious examples, but detailed refutations of Wells’s "icons" can be found at www.ncseweb.org.

The Miller-Urey experiments. — The original experiments that asked whether complex biomolecules could be produced spontaneously on a primordial Earth used an atmospheric composition that is now thought to be unlikely. But to Wells, this progress means that the entire field of research on the origin of life is fraudulent. Recent experiments have synthesized amino acids under more realistic primordial atmospheric and oceanic compositions (Rode, 1999). Wells wrongly claims that these experiments do not work with these alternate atmospheres; the rate of molecular synthesis is lower, but it still occurs.

Wells also misrepresents research on primordial atmospheric oxygen. Misreading current studies, he claims that because there was "free" oxygen in the early atmosphere, the origin of life would have been impossible. He is consistently vague about what he means by "significant amounts" of oxygen in the "early" atmosphere. Fossil and geochemical evidence indicates that life likely arose between 4.0 and 3.8 billion years ago (GA); the earliest fossils are 3.5 GA, so the critical period for atmospheric chemistry is around 3.8 GA. Contrary to Wells’s claims, geochemists generally agree that there was little free oxygen then (Copley, 2001). The question is whether it was "low" (0.25-0.5%) or "significant" (1-2%) compared to present levels (20%). Wells neglects to clarify this for the reader, who might conclude that "significant" levels at 3.8 GA approached today’s 20%. But even levels up to 2% do not preclude the origin of life or slightly reducing atmospheres: amino acids could be synthesized even if small amounts of oxygen were present (Rode, 1999). Wells also ignores many extraterrestrial sources for organic material (Oro, 1994; Orgel, 1998). He then suggests that the "RNA world" hypothesis was proposed to salvage the Miller-Urey paradigm failure, but the link is bogus. This hypothesis suggests how a less complex hereditary molecule than DNA might have preceded it. A "peptide world" hypothesis further narrows the gap between organic molecules and RNA (Rode, 1999; Orgel, 1998), but once again Wells is silent on these critical points.

The "tree of life." — Wells claims that the fossil record does not support a tree of life, and that even molecular evidence cannot save it from being uprooted. This should surprise evolutionary biologists, paleontologists, and molecular biologists alike. His central claim against the pattern of the fossil record is that the "Cambrian Explosion" — the relatively sudden appearance of many of the major animal body plans — is incompatible with Darwin’s prediction of evolution by the gradual accumulation of small differences. Because these differences occur "suddenly" in animal body plans of the Early Cambrian, he says, gradual evolution and thus the tree of life itself are disproven. But the tree of life merely shows the relationships of organisms; the timing of the first appearance of metazoan body plans doesn’t determine the configuration of the tree (they are independent lines of evidence).

Unfortunately, Wells also doesn’t understand what the word "gradual" (Latin, "stepwise") meant in Darwin’s day. (For example, when Darwin witnessed the earthquake in Chile that destroyed hundreds of buildings and lifted the coastline several meters in an instant, he described it as a "gradual" change in his Journal of Researches.) But more importantly, evolutionary theory does not require the slow accumulation of small changes to produce body plan differences. Relatively early-acting small genetic changes in genes that affect features of body plans such as axis orientation, segmentation, and appendage formation can have substantial and immediate phenotypic effects. Anyone who wrote a dissertation on embryology should be aware of the explosive field of evolutionary developmental biology, but apparently Wells’s biological training never passed the blastular stage.

Even on the incorrect assumption that evolution must occur gradually, Wells completely misrepresents the fossil evidence. He asserts that there is no evidence for multicellular life until "just before" the Cambrian explosion, thereby denying the necessary time for evolution to have acted. But Wells is again evasive about what counts as "just before" the Cambrian. Metazoan eggs and embryos and bilaterian trace fossils — which demonstrate the presence of at least an ancestral lineage of all Bilateria — are present 40 (and maybe 70) million years before the Cambrian "explosion" (Valentine et al., 1999). This was enough time for the entire present-day mammalian fauna to evolve after the Age of Dinosaurs ended. Why does Wells call this stretch of time "sudden"?

The Cambrian opens with the "small shelly faunas" that contain archaic members of some living animal lineages, as well as some forms that soon became extinct when the full-blown post-Tommotian faunas of the Cambrian "explosion" later appeared (Valentine et al., 1999). In these later faunas, too, not all component lineages appeared at once. So there is nothing "sudden" about metazoan appearances in the Cambrian, except perhaps in fossilization potential. Wells, however, makes the astonishing claim that the Precambrian fossil record is good enough to prove that no transitional fossils existed, citing Benton et al. (2000) on the completeness of the fossil record. Their paper’s final sentence does literally conclude that the "early" parts of the fossil record are adequate for studying the patterns of life. But the talented Mr. Wells leaves out a critical detail: the sentence refers not to the Precambrian, but to the Cambrian and later times. Ironically, the conclusion of their article directly contradicts Wells’s claim that the fossil record does not support the tree of life. Benton et al. (2000) assessed the completeness of the fossil record by showing that the sequence of appearance of the major taxa is indeed consistent with the independently derived patterns of phylogenetic relationships of the same taxa, using both molecular and morphological analyses of phylogeny. It makes one wonder if Wells actually read the whole paper or hopes that his readers will not.

In the same chapter, Wells attacks genetic phylogenies, claiming for example that the genetic data that place whales within artiodactyls are "bizarre." We agree that molecular analyses can sometimes give jarring results — especially if they’re built on short sequences of single molecules that may not evolve on time scales appropriate to the question. Further studies generally correct this problem. Yet whales were comfortably lodged within artiodactyls long before the supporting data of biochemistry. They are known to have evolved from a mesonychian stem-group of artiodactyls over 55 million years ago. At present the question is not whether whales are artiodactyls, but whether the molecular evidence that hippos are their closest relatives can be reconciled with the fact that there is no evidence of hippolike animals until at least 25 million years later. Evolutionists are quite frank about this current lack of resolution, but Wells is far less frank about the general degree of consilience between molecules and fossils.

The peppered moth. — A particularly egregious example of Mr. Wells’ talents is his treatment of the peppered moth, an "icon" of industrial melanism and natural selection. Voluminous data — not just from Kettlewell’s classic experiments — show that the frequencies of light and dark Biston betularia (and several other moths with multichromatic morphs) change with pollution levels, that light and dark moths are differentially camouflaged against light and dark backgrounds, and that birds eat moths. Most lepidopterists, even Kettlewell’s critics, conclude that although there may be subsidiary causes, bird predation is the major cause of the changes in color frequency (Majerus, 1998), a clear result of natural selection.

Wells picks through the literature in search of studies where even a single detail of the original story may not hold, and implies that such anomalies refute the vast amount of confirmatory data in support of natural selection. He notes a study in which light moths did not increase in frequency after air pollution was reduced, but fails to mention the role of migration and gene flow between populations, or that the light colored morph has now recovered in all populations (Grant et al., 1998). He cites research that claims that lichens are not always present on tree surfaces, but forgets that the color of the substrate is critical, not the presence or absence of lichens. He counters with research on industrial melanism in ladybird beetles that does not follow the peppered moth pattern, as if the lack of selective predation in one species precludes it for another.

Wells accuses Kettlewell of no less than research fraud for affixing light and dark moths to light and dark tree trunks, and recording which ones got picked off by birds in these field experiments. Wells erroneously claims that moths don’t rest on tree trunks, although research shows that moths rest on trunks 26% of the time, and on trunk/branch junctions 43% of the time (Majerus, 1998:123). He also leads the reader to infer that the staged experiments are the only basis of the conclusion that bird predation causes the color changes. But the experiments were conducted to establish whether birds eat peppered moths at all, and if so whether birds differentially select moths that contrast with their backgrounds. The bird predation hypothesis is inferred from the statistical data on observational release and recapture experiments conducted by Kettlewell and others. Combined with experimental evidence that birds differentially select prey from contrasting backgrounds, the inference of bird predation is doubly strengthened. Wells pretends righteous indignation about "fraudulent," "staged" textbook photos of light and dark moths against light and dark backgrounds. But these photos merely illustrate the field experiments that tested Kettlewell’s hypothesis — a reasonable and expected part of science. Can Wells be so ignorant of this investigative tradition?

Those were only three of Wells’s "icons." He also pretends that homology is both evolutionary similarity and evidence for that similarity. He doesn’t know the difference between direct and collateral ancestry. He acts as if he, not scientists and historians, exposed Haeckel’s embryonic drawings as idealized. He completely mistakes scales of time in Darwin’s finches and other natural examples of selection rates. He rails against artists’ drawings of ape-like humans that "justify materialistic claims that we are just animals," as if the drawings were evidence, and as if we were plants instead. In discussing mutant fruit flies, he argues that changes in DNA have nothing to do with the expression of new features — which should surprise the professors in the department that gave him his Ph.D. At lectures given by evolutionary biologists, his acolytes pass out bookmarks with these supposedly fatal objections to evolution in an obvious attempt to fluster speakers who have not prepared for hostile distortions and specious questions. The National Center for Science Education has mounted answers to these "10 Questions to ask your biology teacher about evolution" at www.ncseweb.org.

In a related tactic, Wells’ website (www.iconsofevolution.com) and the second appendix of his book provide a template of stickers to download and paste into textbooks that discuss concepts that he doesn’t like. The thought that anyone would encourage others to deface textbooks for ideological reasons is chilling. Wells concludes with an exhortation to activism, including organizing congressional hearings to stop "supporting dogmatic Darwinists that misrepresent the truth to keep themselves in power" (p. 242). Is this really about science or politics?

Wells is like those kids who used to write to the letters page of Superman comics many years ago. "Dear Editor," they’d write, "you made a boo-boo! On page 6 you colored Superman’s cape green, but it should be red!" Okay, kid, mistakes happen, but did it really affect the story? Wells can’t hurt the story of evolution; like a petulant child, he can only throw tantrums. Detailed reviews (e.g., http://www.don-lindsay-archive.org/creation/icons_of_evolution.html for links) expose Wells’s Ripleyesque deceptions; they do not conclude that the evolutionary concept in question is nonsense.

But even taking Wells’s arguments at face value, if all the evidence for evolution is wrong, what’s his alternate explanation? Special creation of each natural entity? A little divine intervention here and there? An admission that we shouldn’t be researching natural causes of biological evolution? That there can be no natural processes that govern biological patterns, unlike the sciences of physics, chemistry, and astronomy? Wells and his colleagues won’t tell us. They would like to undermine evolution just enough to throw open the door to Intelligent Design as an (entirely untested) alternative. And please, pay no attention to the Man behind the curtain. For more on the intellectual paucity of Intelligent Design, see Miller (1999), Pennock (1999), and Ruse (1998) — or peruse Hume’s (1779) Dialogues concerning Natural Religion, which refuted this version of "Natural Theology" over two centuries ago.

Wells’s book is aimed at a public that is largely ignorant of scientific issues, and it is being marketed aggressively. His arguments, however specious, are well funded and publicized. Icons is being pushed on state and local textbook adoption committees as a supplementary textbook, though its use would result in considerable miseducation — and not just about evolution. Scientists should counter that evolution is a non-controversial scientific theory that explains the patterns of biology, and that dovetails with the evidence from geology, astronomy, physics, and chemistry. It also continues to be central to biomedical, agricultural, and ecological research. But it’s just as important to focus on what they assert. Ask how Wells and his colleagues will replace evolution with Intelligent Design, and where the peer-reviewed research for it is. Have them explain exactly who the Intelligent Designer is, exactly when and where He (She? It? They?) intervened in the history of the Earth and its life, and exactly how this can be shown to everyone’s satisfaction. Nobody here but us scientists? Then let’s make Intelligent Design a testable hypothesis and see how robust it is.

We can all agree that textbooks should represent science more currently and more accurately, and that scientists should have a stronger role in textbook production and adoption; but this is not Wells’s conclusion. He implies (pp. 233-234) that those who in his view are silent about the alleged weaknesses of evolution are guilty of fraud, citing Louis Guenin: "The pivotal concept here is candour, the attribute on a given occasion of not uttering anything that one believes false or misleading. We describe breaches of candour as deception." Considering how silent Wells is on the real evidence and arguments for evolution, his disingenuous citation of Guenin is the pot calling the Kettlewell black. Regardless of religious or philosophical background, Icons of Evolution can scarcely be considered a work of scholarly integrity.

Kevin Padian^{1, 2} and Alan D. Gishlick¹

1National Center for Science Education, PO Box 9477, Berkeley CA 94707-0477; and