Tuesday, April 7, 2009

We like to be fair. Most of us learned fairness on the playground and around board games. Fairness is further reinforced by our educators and schools, and then by the media which often tries to report “both sides” of a controversy. We hold these values dear. When I taught composition to freshman college students, the most commonly used sentence was “Everyone is entitled to their opinion.”

And of course I have to agree with this sentiment. I like fairness and I value open-mindedness very highly. But when fairness is exploited at the expense of truth, it’s time to re-evaluate. Being fair and open-minded does not mean giving equal weight to all ideas, it means giving proper weight to ideas based on the strength of the evidence and arguments supporting them.

I suspect that people, including school board members and educators, who consider Intelligent Design (or other variations of creationism) as an alternative to the theory of evolution mean well and are acting only in the interest of fairness and open-mindedness. But they are doing themselves and their students a great disservice. It’s like proposing the ideas of the Flat Earth Society as an alternative to the Spherical Earth Theory.

Jerry Coyne, in Why Evolution is True, complains that the story of evolution has not been told often enough or well enough, and that it is simple ignorance, even among scientists, of the extraordinary wealth of evidence in support of evolution, that leaves people susceptible to creationist ideas. The truth is that Intelligent Design proponents ask some intriguing questions of nature, the answers to which are anything but obvious (How could an eye evolve? Or a wing? How does a cow-like creature transition into a whale-like creature?). But what is largely unknown is that evolutionary thoerists have asked the very questions and come up with answers for them, answers that agree perfectly with the fossil record and with what evolutionary theory predicts. People simply need to be aware of all that evolutionary theory has allowed us to learn about the natural world.

The evidence Coyne outlines is vast and can leave no doubt in the reader that species evolved through natural selection very much as Darwin first established 150 years go (Happy Anniversary, Origin of Species!). Using the theory of evolution, scientists have repeatedly been able to predict the existence of extinct species and then have been able to find examples of those creatures in the fossil record, nearly exactly where the theory predicted. The power of selection has been clearly demonstrated by plant and animal breeders, who, in the course of a few thousand years, have been able through artificial selection to create chihuahuas, blood hounds, and great danes from a single species of wolf. Native American farmers bred corn from a species that resembles crab grass. Certainly these examples show the potential for modification through selection that exists in living species. What’s more, natural selection has been observed in real time in nature—on the Galopogas islands, finches responded to tougher seed husks by developing larger beaks in a mere ten years. Furthermore, natural selection and speciation have been demonstrated in the laboratory. In one experiment, new species of bacteria emereged in a laboratory environment in only weeks . Given all of this evidence, it becomes much less difficult to believe that the forces of natural selection, applied over hundreds of millions of years, could create the diversity of life on this planet and even lead ultimately to human beings.

Coyne never lays out exactly what the ideas of Intelligent Design and other creationists are. Rather he answers ID proponents and creationists point-by-point in passing as he lays out an airtight argument for evolution.

What is most valuable in this book, though, isn’t its excellent argument, but rather Coyne’s illumination of the myriad ways in which evolution has worked on species, the fascinating adaptions that have developed (some of them blatantly unintelligent), and the clever and dedicated science that explains our natural world. Any threat to that kind of knowledge demands a defense.

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