This is an essay I wrote a few years ago when Jonathan Wells published the execrable Icons of Evolution. It was to be published in a book that never came to fruition, so I put it on my website. It is appropriate for The Panda's Thumb, I think. Read it, and weep, seriously...
Let's suppose that you are of the belief that no artificial thing can fly. Perhaps you are a member of the Omnian religion, and the sacred Book of Om states 'nothing not made by Om can fly through the air'. What can you do in a society that regularly sends aircraft from one side of the planet to the other? How can you deal with the evidence?
Well, there are a few things you might do. First, you might deny that things made by humans do fly. You might say they are in fact borne up by Om's invisible minions. You might pick holes in the gaps of knowledge in modern aerodynamics, and argue that because turbulent flows cannot be predicted, aerodynamics is not a science. Or, you might look at aerodynamics textbooks.
Any secondary school physics text or pilot licence manual will tell you that aerofoils generate lift because of the Venturi effect. Because a wing is curved at the top and not at the bottom, air flows faster at the top than the bottom, so the pressure of air below the wing is greater than the pressure above it. This means that the wing is pushed up from below, and so generates lift. Textbooks are usually illustrated with simple flow diagrams or wind tunnel photographs showing the way air is compressed above the wing section. Let us call this 'the best evidence of the Venturi hypothesis'.
But in the technical literature, you will find that this is not the real or only explanation of lift. Air is also forced downwards, and on Newton's second law that every action causes an equal and opposite reaction, this causes the wing to move in the opposite direction - up. Moreover, flat sheets at the right angle of attack can generate lift in this way, and so can inverted wing sections, as the audience at an air show can attest on seeing aircraft fly upside down.
Clearly, the textbooks are at odds with the science. Clearly, the science is at odds with itself. Clearly, the 'theory of flight' is a myth, founded on a series of false icons (nice touch, that - 'icon' suggests, without needing to defend it, that aeronautical engineering is a religion and we can seek the same privileges for Omnian theology as aircraft design has). Hence, it must be that the 'hypothesis' that aircraft are borne through the air has the same standing in science as aerodynamics does.
How then can we explain the singular lack of contribution by Omnian theology to aircraft design, manufacture, and operation? How does the Book of Om help air industry economists maximise fuel use and prevent accidents? In what way can Om's minions be appeased to make air travel better? Why don't Omnian 'minion scientists' publish in scientific journals?
The obvious answer is that there is a conspiracy of fraud, silence, and greed by aeronautical engineers to gain as much research money as they can. To attain this, they freeze out Omnian 'minion science' by making aerodynamics orthodoxy a test of competence and so limit access to publications and funding grants. Even when attempts are made to set up a Minion Discovery Institute at a regional university, those conspiratorial frauds that masquerade as scientists object and force its founders to adhere to the 'standards' of the fake orthodoxy. But the Minion Hypothesis will win in the end, yadda yadda yadda.
This little tale of absurdity and paranoia not coincidentally resembles real or actual events and people. The very same line of argument is presented, suitably dressed up in academic-sounding language, by Jonathon Wells in the final chapter of his Icons of Evolution. All the textbook examples (all of them?) are false (really?) and so evolution is a myth. Darwinism is just a money grubbing exercise. This may come as something of a surprise to evolutionary biologists, whose research is being funded less and less in the face of the triumphal march of molecular biology, but they are in it for the wealth, it seems. If they were really smart, I think they would have found some other way to make money - perhaps by setting up a fake institute that panders to religiously-inspired antiscience prejudice, or by running a televangelism show.
The preceding chapters [of the book this is a contribution to - JSW] have dealt with the errors and misrepresentations in Wells' book. I wish to discuss Wells' claim that evolution is a 'myth'. Philosophical doubts about the factuality of evolution come, in the main, from non-scientists such as Phillip Johnson (1991, a law professor), and William Dembski (1998, a philosophy graduate). But Wells is different - he has a degree in biology. That he got it at the instruction of his religious leader, the Rev. Sun Myung Moon of the Worldwide Unification Church, in order to discredit evolution before he had even reviewed the evidence, and that his first degree is in theology from that denomination, is relevant only to his motivations. The issue is whether he, as a biologist, can maintain that evolution is not a fact. The answer is that he can do this only through an enormous amount of bad faith.
'Evolution' is really a number of theories, and those theories, like all science, change from time to time, so that what is being spoken of must be indexed to the date. We will attend here to modern theories. Moreover, unlike a religion under central control, science is actually not a set of doctrines to which assent is required. Some scientists disagree with other scientists in their own discipline. So there is some play in evolutionary theories. This must be borne in mind. The simple fact that scientists aren't 100% in agreement is not evidence against an entire discipline such as evolutionary biology (or it is evidence against any science whatsoever).
When Wells attacks 'evolution', there is a strong implication that if there is trouble in an example with selection as in the peppered moth case, there is trouble for the whole of evolutionary biology. We therefore need to be clear about what 'evolution' really is. The main evolutionary theories of today are three: the theory of phylogenetic common descent, the theory of modern population genetics, and the theory of selection. These are not independent theories, but neither are they identical. Problems with any one of them is not immediately a problem with all of them. Let us consider each in turn.
The word 'phylogeny' means a tree of descent. The idea is that things that are closely related in the living world are so because they evolved from common ancestral species. Common descent is offered as an explanation of biological relationships, as well as of the distribution of organisms. In 1855, a few years before the Origin of Species was published, Alfred Russel Wallace published a paper in which he asserted that new species always come into existence next to their nearest relatives. This pattern is explained also by common descent.
Modern population genetics is the fusion of biometrics (the statistics of populations of organisms), Mendel's theory of heredity (that traits are passed on as independent factors) and molecular biology. One of the outcomes of this discipline is that we can expect under certain circumstances that populations will differ in their genetic makeup, and that with other processes taken into account (mutation, recombination of genes through mating, etc), populations can be expected to evolve. One of the ways this can happen is through chance (random genetic drift); another is by our third theory:
Selection is the 'mechanism' of evolution. More accurately, it is the name we give to the process of the ways in which different traits will end up in different frequencies in a population depending on how the bearers of those traits do at reproducing because of the way those organisms live in their environments. There are several flavors of selection: artificial, sexual and natural. The first is what breeders do, and it was on the parallel with this that Darwin developed his theory of selection. Sexual selection is evolution driven by mate choices. And natural selection is everything else that determines the frequencies of traits (other than drift).
Now all of these theories have a large body of evidence, experimentation and discussion both at the philosophical level and at the scientific level. Phylogeny is routinely debated in the sense that it is discussed whether the evidence supports a particular reconstruction of the history of some group. But the debates about whether common descent is a good explanation of relatedness, or affinity as it was once called, was held a century and a half ago, and despite attempts to revisit it by creationists, not a single biologist doubts that some common ancestry explains why species are similar (Brooks and McLennan 1991; Sober 1994). This is because the hypothesis not only explains, but it predicts. It predicts, for example, that if a particular enzyme plays a functional role in two mammalian species such as mice and monkeys, it almost certainly does in humans. All of medical research is predicated on this assumption.
The mechanisms of genetics are now so ordinary in science that to doubt them is to invite comparisons with the crackpot fringe. We manipulate genes, identify them and predict their behavior in populations. We can debate whether two particular traits are homologous if the genes are different, or two particular genes are homologous if their effects differ, but we cannot doubt that there are any homologies due to descent at all. Conceptual difficulties in a term - and there are some serious ones in the case of 'homology' (Hall 1999; Hall 1994) - are quite common in science and are not evidence of the falsity of a theory that uses it in biology or any other science. Mostly, conceptual confusion is the domain of philosophers.
Natural selection is debated by scientists (Williams 1992). Some think it is the single most important mechanism of evolution. Others think it is a major but not sole mechanism. Nobody doubts that if a trait is adaptive that it is the result of selection in whole or main part. There is a century and a half of solid experimentation on selection. It is a major factor in drug development, disease management, and recently in engineering. One book (Bell 1996) summarised the biological evidence and experimentation for selection in hundreds of pages of terse description. Is all of this in doubt if Kettlewell placed two butterflies on a tree trunk to illustrate the differences in camouflage? Thousands of experiments, including the classic ones of John Endler on Jamaican guppies, or the Grants on Darwin's finches in the Galápagos Islands (Weiner 1994) - all this is discredited if a single example in textbooks is false? Really. Anyone who thinks that either fails to understand science and evidence, or understands all right but hopes disingenuously that their audience doesn't. Cynical though it may be, I can only think that Wells is in the latter camp, since he has a biological education. He should know how science operates.
Let us assume, contrary to the evidence presented in the previous chapters, that Wells is right about every single example and that the textbooks he 'grades' do in fact perpetuate myths. Is evolution then not a fact? What a textbook is designed for is teaching, not research. Research papers get published in the technical journals and anthologies, which are aimed at those already competent in the disciplines. Textbooks aim to get ideas over so that graduates are capable of understanding the technical literature. But before somebody becomes a professional biologist they have long since left textbooks behind. If it turned out that every example or idea in the undergraduate textbook were flawed in some way, the graduate would still be prepared for the science, because education comes from teachers. By the time a student is in third year, they only refer to textbooks on subjects they don't know much about. Of course, the profession would not permit a textbook that was completely flawed to be used to teach (although I suppose a clever teacher could use a textbook of, say, the 1930s, to teach modern biology by pointing out the differences to the technical literature). So the existence of false examples in textbooks is not in itself enough to discredit the discipline. Textbooks are like flowers on the tree of a science - most of the substance is behind them and relatively independent of them, and textbooks, like flowers, are there for propagation not growth.
Wells' attack is a small-minded and fundamentally antiscience approach to one of the most sublime examples of human endeavor. He is not basing his criticisms on reason by appealing to experience or evidence; he is appealing to emotions through rhetoric. This is not a book that seeks truth, but one which runs from it. His supporting website for example, at the date of writing has a downloadable set of labels to be printed out on standard laser labels and placed on textbooks 'warning' the reader of errors. The instructions state that of course these labels should only be used on copies owned by the user, but if Wells thinks that people who routinely glue pages of textbooks together in university and school libraries will respect this injunction, he is naïve. Personally, I find it hard to accept that he thought they would, and that the injunction is there just to cover him and his publishers legally, and if that is so, this is bad faith of the worst kind.
Who exactly is Wells writing to in Icons? It is clearly not going to sway a single informed and educated scientist, so it is hardly a call to reform science. Even those who are well-read amateurs of evolutionary theory are going to see this book for what it is, so it can only be aimed at one or both of two audiences: the choir and the influential. It preaches to the choir and so it reinforces the satisfied glow of ignorance with a veneer of respectable scholarship, which the choir are ill equipped to see through. And it also seeks to sway populist politicians, primarily but not exclusively in the United States, against the funding and teaching of evolutionary science.
What sort of a mark would we give 'standard' anti-evolutionary textbooks if we used the criteria of science rather than the superficial and emotive criteria Wells has used? Not one of them is designed to increase knowledge about biology. Indeed, all of them are designed to cast doubt on any aspects of biology that do not suit them on no other basis than the authority of their philosophy or religion. There is no research program other than a vaguely stated 'find design' injunction. There is no respect for evidence or experiment. The mark has to be the lowest possible - in my day it would have been NP, a no-pass, but let us call a digging implement a shovel: Wells and his colleagues fail outright.
The entire case brought against evolutionary biology by Wells and those he draws upon is a negative one. It consists of finding 'difficulties' rather than in doing any actual scientific work, and neither he nor anyone he relies upon seeks to advance knowledge. He achieves his true goals by calling facts 'myths'. There is no shred of reasonable doubt in the mind of any specialists that the three main hypotheses of evolution - phylogeny, genetics, or selection - are facts. Each has been observed to occur. New species have been seen to split off from existing ones, gene frequencies have changed and mutations (yes, some of them 'beneficial') have been seen, and selection has repeatedly been observed, measured, predicted correctly, and even experimentally reproduced. In science, a hypothesis 'graduates' to a fact when it is observed or is made to happen in as little as a single case. Under no honest or charitable interpretation can 'evolution' be called a 'myth - and certainly not on such vague, misleading and question-begging grounds as Wells uses.
Om would be pleased if one of his apologists could do as well as Wells. But planes would still fly, and life still evolves through natural selection, common descent, and the known workings of genetics.
Thanks to Troy Britain, Carl Johnson, Dave Matson for comments and information, and Paul Heinrich and Kevin O'Brien for the suggestion and implementation of this book.
Bell, Graham. 1996. Selection: The mechanism of evolution. New York: Chapman and Hall.
Brooks, Daniel R., and Deborah A. McLennan. 1991. Phylogeny, ecology, and behavior: a research program in comparative biology. Chicago: University of Chicago Press.
Dembski, William A. 1998. The design inference: eliminating chance through small probabilities. Cambridge; New York: Cambridge University Press.
Hall, BK, ed. 1999. Homology, Novartis Foundation Symposium 222. Chichester; New York: John Wiley and Sons.
Hall, Brian K. 1994. Homology: the hierarchical basis of comparative biology. San Diego; Sydney: Academic Press.
Johnson, Phillip E. 1991. Darwin on trial. Washington, DC, Lanham, MD: Regnery Gateway.
Sober, Elliott. 1994. Conceptual issues in evolutionary biology. 2nd ed. Cambridge, Mass.: MIT Press.
Weiner, Jonathan. 1994. The beak of the finch: a story of evolution in our time. 1st ed. New York: Knopf.
Williams, George C. 1992. Natural selection: domains, levels, and challenges. New York: Oxford University Press.
'Father's [Rev. Moon's] words, my studies, and my prayers convinced me that I should devote my life to destroying Darwinism, just as many of my fellow Unificationists had already devoted their lives to destroying Marxism. When Father chose me (along with about a dozen other seminary graduates) to enter a Ph.D. program in 1978, I welcomed the opportunity to prepare myself for battle. - I eventually decided to join the fray by returning to graduate school in biology. I was convinced that embryology is the Achilles' heel of Darwinism; one cannot understand how organisms evolve unless one understands how they develop. In 1989, I entered a second Ph.D. program, this time in biology, at the University of California at Berkeley. While there, I studied embryology and evolution.'
However, Wells says in the Preface to Icons that
'During my years as a physical science undergraduate and biology graduate student at the University of California, Berkeley, I believed almost everything I read in my textbooks. I knew that the books contained a few misprints and minor factual errors, and I was skeptical of philosophical claims that went beyond the evidence, but I thought that most of what I was being taught was substantially true.As I was finishing my Ph.D. in cell and developmental biology, however, I noticed that all of my textbooks dealing with evolutionary biology contained a blatant misrepresentation: Drawings of vertebrate embryos showing similarities that were supposed to be evidence for descent from a common ancestor. But as an embryologist I knew the drawings were false. ...'
These two accounts are inconsistent, and call into question the integrity of Wells' attack.
 Like flowers, also, textbooks can sometimes achieve their purpose by misdirection or mimicry, but neither will achieve this if too much deception occurs overall.
 Accessed on 29 November 2000 at <http://www.iconsofevolution.com/tools/warningLabels.pdf>. [Note: this link no longer works - JSW May 2004]
 Wells has the following text in his appendix II
'Suggested Warning Labels for Biology TextbooksBiology textbooks contain a wealth of valuable information. Just because they misrepresent the evidence for evolution doesn't mean that everything they teach is incorrect. Existing textbooks can and should be used until publishers come out with corrected ones. In the meantime, students should be warned, where necessary, that their books misrepresent the truth. Warning labels such as those below can be used for this purpose, but they should be applied only by, or under the direction of, the owner of the book.'