© 2009, Dustin J. Penn V. Myths and Misconceptions A. General Misconceptions about Evolution "Thus the creationist's question - 'What is the use of half an eye?' - is actually a lightweight question, a doddle to answer. Half an eye is just 1 per cent better than 49 per cent of an eye, which is already better than 48 percent, and the difference is significant." - Richard Dawkins, 19951 Summary There are many myths and misconceptions about evolution and this section provides an overview of the most common ones, especially those promoted by the intelligent design movement and other creationists. Misconceptions about evolution have been addressed by many scientists and educators, both religious as well as non-religious ones.2-10 The many misconceptions about evolution help explain its low acceptance by the public, especially when combined with the numerous misconceptions about the implications of evolution for humans. (See Section V.B) Myths: 1. Myth: Evolution is a theory, not a fact 2. Myth: Evolution is scientifically controversial 3. Myth: Evolution cannot be observed or scientifically tested 4. Myth: The Earth is only 6000 years old, so there has not been enough time for evolution to occur 5. Myth: Evolution violates the Second Law of Thermodynamics 6. Myth: The complex, functional features of organs cannot be explained by evolution 7. Myth: Evolution is merely a random process and therefore cannot explain life 8. Myth: Darwin’s theory fails because it does not explain the origin of life and other mysteries of life 1. Myth: Evolution is a theory, not a fact Creationists often claim that evolution is "just a theory," but such claims are misleading.7 Evolution is both a fact and a theory (the theory is Darwin’s theory of natural selection). However, evolution is not a theory in the colloquial sense of the word, which implies a mere hypothesis, conjecture, or speculation. Darwin’s theory is a theory in the scientific sense, which means that it is a comprehensive explanation strongly supported by evidence, and useful for making predictions. Other scientific theories include the Germ Theory, Atomic Theory and Quantum Theory, and Einstein’s Theory of Relativity. Scientific theories are not less than scientific laws, contrary to what is often assumed. Scientific laws describe facts whereas theories explain them. Darwin’s Theory, for example, explains the fact of evolution. It is crucial to understand that evolution — like all facts in science — remains open to question. This tentativeness of facts is a fundamental distinction between science and religion. This is precisely the reason that "intelligent design" and "creation science" are not sciences: no amount of empirical evidence will alter creationists’ faith in creationism. Thus, evolution is not "just a theory", in the usual sense of the word, and it is accepted as a fact by the vast majority of scientists. The "just a theory" claim is a misrepresentation that exploits the fact that scientists use the word theory differently than the general public.11-12 For example, a school board in Atlanta, Georgia (USA) placed disclaimer stickers on Biology textbooks to warn students that 13 Figure 1. Disclaimer stick- "evolution is a theory, not a fact" (Figure 1). The disclaimer was er.13 meant to appease more than 2,000 parents who complained about the absence of biblical creation in science textbooks. In 2005, a federal judge ruled that the disclaimers were an unconstitutional endorsement of religion. The board challenged the decision and then settled out of court: the board agreed to drop the disclaimers and to pay the plaintiff’s legal fees in the case. Nevertheless, the creationist lobby continues to promote the "just a theory" myth. 2. Myth: Evolution is scientifically controversial Creationists often misrepresent evolution as "a theory in crisis".14 Evolution has long been accepted as an established fact among the vast majority of scientists. Scientists spend no more time debating the fact of evolution than the existence of atoms. Scientific controversies about evolution exist, and they can be heated, but these debates are over how – not whether – evolution occurs. For example, some scientists debate the relative importance of natural selection versus genetic drift and other processes for explaining the evolution of life. The scientists involved in these debates, such as S.J. Gould (1941-2002), have voiced their objections to being misrepresented by creationists (Figure 2)11,16-18,21. Creationists continue to promote the myth that evolution is scientifically controversial as a Figure 2. Stephen J. deliberate strategy to raise doubts about evolution, just as corporate lobbyists Gould11,16-18,21 use this tactic to create confusion and doubts about the health risks of tobacco and climate change due to fossil fuels.15 Evolution is controversial, but the debates are political rather than scientific, and creationists generate the controversies themselves. 3. Myth: Evolution cannot be observed or scientifically tested Since creationists have failed to convince courts that "creation science" and "intelligent design" are legitimate sciences, they now assert that evolution is not a science either. In particular, they argue that no one was around to observe whether or how life originated, and therefore evolution is untestable. This claim is misleading for the following reasons. First, it misrepresents the importance of indirect evidence in science. Scientific facts come from both indirect and direct observations, and there is a great deal of indirect evidence for evolution, such as the fossil record. How can the fossil record potentially disprove evolution? J.B.S. Haldane, one of the founders of evolutionary biology, once pointed out that evolution would be disproved if someone discovered a fossil rabbit in the Figure 3. Experimen- Precambrian Era (i.e., millions of years before mammals had even evolved). tally testing evolu- tion.23 Second, no one was around to observe the evolution of life, however, there is a tremendous amount of direct evidence showing that life continues to evolve. Scientists have recorded genetic changes over time in many species, such as the evolution of pesticide resistance in crop pests. A large and growing number of experimental studies, mostly with microbes and fruitflies, confirm evolution and Darwin’s theory (Figure 3). Some studies have even documented speciation in the laboratory.22 Thus, evolution is testable, and it is supported by a massive amount of evidence, direct as well as indirect. 4. Myth: The Earth is only 6000 years old, so there has not been enough time for evolution to occur Creationists who promote this notion ("Young Earth Creationists") base their estimate of the age of the Earth on Genesis, and reject radiometric dating techniques that show the Earth is around 4.6 billion years old.24-25 The 4.6 billion years estimate comes from a large number of measurements using different dating methods, and there is no scientific controversy about this figure. There used to be a scientific controversy about the age of the Earth. In fact, one of the most important objections to evolution in the 1800’s was the age of the Earth. William Thomson (a.k.a. Lord Kelvin) estimated that the Earth was only 24 to 400 million years old, which if correct would have indeed posed a problem for Darwin. Thomson’s calculations turned out to be wrong, however (as it was Figure 4. Scientific dating techniques not yet known that heat from the sun is generated by radioactive fusion). Once radioactive dating methods were discovered, they showed that there has been more than enough time for evolution to occur. Thus, creationists' belief that the earth is only 6000 years old is not a trivial mistake, and as Richard Dawkins points out, it is like believing that the distance from New York to San Francisco is only 28 feet! Not all Creationists are Young Earth Creationists, and many other creationists accept the scientific estimates for the age of the Earth. These "Old Earth Creationists" realize that they have lost this battle and instead are focusing on other criticisms of evolution. 5. Myth: Evolution violates the Second Law of Thermodynamics To make "intelligent design" and "creation science" appear to be science, creationists have increasingly been using scientific jargon. For example, creationists sometime argue that evolution defies the Second Law of Thermodynamics. Since the universe tends to decrease order (entropy) rather than increase order and complexity, creationists claim that evolution is inconsistent with the physics. However, the Second Law only applies to closed Figure 5. No miracles systems, in which energy cannot enter a system, whereas the earth is an in Science! open system with energy provided by the sun and captured by plants in photosynthesis.26 Evolution does not violate the laws of thermodynamics any more than does photosynthesis. The "evolution-violates-the-Second-Law" notion misrepresents physics as well as biology. 6. Myth: The complex, functional features of organs cannot be explained by evolution Creationists argue that the amazing complexity of living organisms cannot be explained by Darwinian evolution (or any other natural process), and can only be explained by a supernatural Creator. The idea that the complexity and design-like features of life provide evidence for design by a supernatural agent is called the "Argument from Design" or "teleological argument", and it goes back to Thomas Aquinas and even ancient Greek philosophers.27 The most well-known version is William Paley’s "watchmaker analogy" from his book, Natural Theology. Paley argued that if one found a watch in the woods, full of complex and intricate working parts, one would have to conclude that it was designed by a watchmaker. It could not have arisen by chance. Similarly, complex traits of organisms, such as eyes, are taken as evidence for purposeful design by a supernatural Creator.