Free Why Darwin Matters by Michael Shermer Page A

supernatural forces operating outside this world. Following that thinking, there is no point in searching for medical cures in the natural world; we should throw out all medical knowledge and turn purely to prayer, without trying any treatments. But medicine, like evolution and other sciences, deals with natural explanations for natural phenomena, and even with only a rudimentary understanding of the natural world we should seek answers from the known, natural world first. Before assuming that the unknown is the only possible way to account for the complexity and diversity of life, it must first be demonstrated that known forces and processes cannot do the job.
    Burden of Proof, or, extraordinary claims require extraordinary evidence
.
    Darwin’s original claim of evolution by means of natural selection was an extraordinary claim in its time, so he was required to provide extraordinary evidence for it. He did, and evidence has continued accumulating ever since. Today, the burden of proof is on creationists and Intelligent Design advocates to provide extraordinary evidence for their extraordinary claim that a supernatural being of great power and intelligence performed a supernatural act in place of or contrary to natural law. They have yet to do so.
    Either-Or Fallacy, or, disproving A does not prove B
.
    The either-or fallacy is the false assumption that there are only two positions, A and B, so if A is wrong then B must be right. The fallacy is that discrediting A does not demonstrate B. Both A and B could be wrong and a third alternative could be correct. Creationists employ the either-or fallacy when they claim that life was either divinely created or naturally evolved. By attempting to discredit evolution they hope to draw the conclusion that creationism is true. In science, however, it is not enough to just debunk the accepted theory. You must also replace it with a theory that explains both the “normal” data accounted for by the old theory as well as some of the “anomalous” data not accounted for by the old theory. At the end of my debate with Kent Hovind, for example, he was asked by an audience member: “What is the best evidence for the creation?” He answered: “The impossibility of the contrary” (that is, evolution). In that simple statement, Hovind confessed the scientific sin of creationism and Intelligent Design: Disproving evolution does not prove creationism.
    The Fossil Fallacy, or, one datum does not a science make
.
    In debates with creationists they often demand “just one transitional fossil” that proves evolution, pointing to a gap in the fossil record. When I fill the gap—for example, with
Ambulocetus natans
, a transitional fossil between ancient land mammals and modern whales—they respond that there are now
two gaps
in the fossil record! This is a clever retort, but it reveals a deep error in epistemology that I call the
Fossil Fallacy:
the belief that a single “fossil”—one bit of data—constitutes proof of a multifarious process or historical sequence. 5
    Proof is derived not through a single piece of evidence, but through that convergence of evidence from numerous lines of inquiry, all of which point to an unmistakable conclusion. We know evolution happened not because of a single transitional fossil such as
Ambulocetus natans
, but because of the convergence of evidence from such diverse fields as geology, paleontology, biogeography, comparative anatomy and physiology, molecular biology, genetics, and many more. Paleontologist Donald Prothero, for example, employs the convergence technique in revealing that in addition to at least eight transitional fossils from land mammals to whales, DNA from living specimens reveals that modern whales descended from even-toed hoofed mammals called
artiodactyls
. Whales, it turns out, are most closely related to the hippopotamus. 6
    No single discovery from any one field constitutes proof of evolution. It is the mass of data together,