Jonathan Wells - Science or Myth?

from: Science or Myth?

Why Much of What We Teach About Evolution Is Wrong

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. Not only did they distort the embryos they purported to show, but they also omitted earlier stages in which the embryos look very different from each other.

My assessment of the embryo drawings was confirmed in 1997, when British embryologist Michael Richardson and his colleagues published an article in the journal Anatomy and Embryology, comparing the textbook drawings with actual embryos. Richardson was subsequently quoted in the leading American journal Science as saying: "It looks like it's turning out to be one of the most famous fakes in biology."

Yet most people remain unaware of the truth, and even biology textbooks published after 1997 continue to carry the faked drawings. Since then, I have discovered that many other textbook illustrations distort the evidence for evolution, too. At first, I found this hard to believe. How could so many textbooks contain so many misrepresentations for so long? Why hadn't they been noticed before? Then I discovered that other biologists have noticed most of them, and have even criticized them in print. But their criticisms have been ignored.

The pattern is consistent, and suggests more than simple error. At the very least, it suggests that Darwinism encourages distortions of the truth. How many of these distortions are unconscious and how many are deliberate remains to be seen. But the result is clear: Students and the public are being systematically misinformed about the evidence for evolution.

This book is about that evidence. To document it, I quote from the peer-reviewed work of hundreds of scientists, most of whom believe in Darwinian evolution. When I quote them, it is not because I want to make it sound as though they reject Darwin's theory; most of them do not. I quote them because they are experts on the evidence.

 *

Theories that survive repeated testing may be tentatively regarded as true statements about the world. But if there is persistent conflict between theory and evidence, the former must yield to the latter. As seventeenth-century philosopher of science Francis Bacon put it, we must obey Nature in order to command her. When science fails to obey nature, bridges collapse and patients die on the operating table.

Testing theories against the evidence never ends. The National Academy's booklet correctly states that "all scientific knowledge is, in principle, subject to change as new evidence becomes available." It doesn't matter how long a theory has been held, or how many scientists currently believe it. If contradictory evidence turns up, the theory must be reevaluated or even abandoned. Otherwise it is not science, but myth.

To ensure that theories are tested objectively and do not become subjective myths, the testing must be public rather than private. "This process of public scrutiny," according to the National Academy's booklet, "is an essential part of science. It works to eliminate individual bias and subjectivity, because others must also be able to determine whether a proposed explanation is consistent with the available evidence"

Within the scientific community, this process is called "peer review." Some scientific claims are so narrowly technical that they can be properly evaluated only by specialists. In such cases, the "peers" are a handful of experts. In a surprising number of instances, however, the average person is probably as competent to make a judgment as the most highly trained scientist. If a theory of gravity predicts that heavy objects will fall upwards, it doesn't take an astrophysicist to see that the theory is wrong. And if a picture of an embryo doesn't look like the real thing, it doesn't take an embryologist to see that the picture is false.

So an average person with access to the evidence should be able to understand and evaluate many scientific claims. The National Academy's booklet acknowledged this by opening with Thomas Jefferson's call for "the diffusion of knowledge among the people. No other sure foundation can be devised for the preservation of freedom and happiness." The booklet continued: "Jefferson saw clearly what has become increasingly evident since then: the fortunes of a nation rest on the ability of its citizens to understand and use information about the world around them."

U. S. District Judge James Graham affirmed this Jeffersonian wisdom in an Ohio newspaper column in May 2000. Graham wrote: "Science is not an inscrutable priesthood. Any person of reasonable intelligence should, with some diligence, be able to understand and critically evaluate a scientific theory"

Both the National Academy's booklet and judge Graham's newspaper column were written in the context of the present controversy over evolution. But the former was written to defend Darwin's theory, while the latter was written to defend some of its critics. In other words, defenders as well as critics of Darwinian evolution are appealing to the intelligence and wisdom of the American people to resolve the controversy.

This book was written in the conviction that scientific theories in general, and Darwinian evolution in particular, can be evaluated by any intelligent person with access to the evidence.

*

Evidence for evolution

When asked to list the evidence for Darwinian evolution, most people-including most biologists-give the same set of examples, because all of them learned biology from the same few textbooks. The most common examples are:

• a laboratory flask containing a simulation of the Earth's primitive atmosphere, in which electric sparks produce the chemical building-blocks of living cells;

• the evolutionary tree of life, reconstructed from a large and growing body of fossil and molecular evidence;

• similar bone structures in a bat's wing, a porpoise's flipper, a horse's leg, and a human hand that indicate their evolutionary origin in a common ancestor;

• pictures of similarities in early embryos showing that amphibians, reptiles, birds and human beings are all descended from a fish-like animal;

• Archaeopteryx, a fossil bird with teeth in its jaws and claws on its wings, the missing link between ancient reptiles and modern birds;

• peppered moths on tree trunks, showing how camouflage and predatory birds produced the most famous example of evolution by natural selection;

• Darwin's finches on the Galapagos Islands, thirteen separate species that diverged from one when natural selection produced differences in their beaks, and that inspired Darwin to formulate his theory of evolution;

• fruit flies with an extra pair of wings, showing that genetic mutations can provide the raw materials for evolution;

• a branching-tree pattern of horse fossils that refutes the oldfashioned idea that evolution was directed; and

• drawings of ape-like creatures evolving into humans, showing that we are just animals and that our existence is merely a by-product of purposeless natural causes.

These examples are so frequently used as evidence for Darwin's theory that most of them have been called "icons" of evolution. Yet all of them, in one way or another, misrepresent the truth.

Science or myth?

Some of these icons of evolution present assumptions or hypotheses as though they were observed facts; in Stephen Jay Gould's words, they are "incarnations of concepts masquerading as neutral descriptions of nature." Others conceal raging controversies among biologists that have far-reaching implications for evolutionary theory. Worst of all, some are directly contrary to well-established scientific evidence.

Most biologists are unaware of these problems. Indeed, most biologists work in fields far removed from evolutionary biology. Most of what they know about evolution, they learned from biology textbooks and the same magazine articles and television documentaries that are seen by the general public. But the textbooks and popular presentations rely primarily on the icons of evolution, so as far as many biologists are concerned the icons are the evidence for evolution.

Some biologists are aware of difficulties with a particular icon because it distorts the evidence in their own field. When they read the scientific literature in their specialty, they can see that the icon is misleading or downright false. But they may feel that this is just an isolated problem, especially when they are assured that Darwin's theory is supported by overwhelming evidence from other fields. If they believe in the fundamental correctness of Darwinian evolution, they may set aside their misgivings about the particular icon they know something about.

On the other hand, if they voice their misgivings they may find it difficult to gain a hearing among their colleagues, because (as we shall see) criticizing Darwinian evolution is extremely unpopular among English-speaking biologists. This may be why the problems with the icons of evolution are not more widely known. And this is why many biologists will be just as surprised as the general public to learn how serious and widespread those problems are.

The following chapters compare the icons of evolution with published scientific evidence, and reveal that much of what we teach about evolution is wrong. This fact raises troubling questions about the status of Darwinian evolution. If the icons of evolution are supposed to be our best evidence for Darwin's theory, and all of them are false or misleading, what does that tell us about the theory? Is it science, or myth?