Sunday, January 01, 2006

Evolution is accepted science.

The so-called controversy over Evolution as settled science has been much in the news over the last couple of years. Unfortunately it has been written about mainly by political writers rather then science writers. Science writers generally provide the context - the background - that shows why Evolution is so widely accepted among scientists.

The political writers, looking for the newsworthy, instead focus on the rather outrageous "scientific" claims made by the Creationists. In focusing on the outrageous, and hence newsworthy, claims, the political writers give too much credence to them. They fail to demonstrate the scientific falsity of the creationist claims.

Chris Mooney and Matthew C. Nisbet wrote an excellent article (published in The Columbia Journalism Review). Here is an excerpt:
“Nothing in biology makes sense except in the light of evolution,” the famed geneticist Theodosius Dobzhansky wrote in 1973. What Dobzhansky calls “evolution,” Charles Darwin himself often called “descent with modification,” but the basic idea is the same — that the wide variety of organisms occupying the earth today share a common ancestry but have diversified greatly over time. The main force driving that process, Darwin postulated, was “natural selection.” In brief, the theory works like this: natural variations make some organisms better equipped than others for their various walks of life, and these variations are heritable. As a result, some organisms will be more likely to survive than others and will therefore pass on advantageous traits to their offspring — a process that, over vast stretches of geological time, can bring about division into species and, ultimately, the diversity of life itself.

Since Darwin’s time modern science has dramatically bolstered this theory with evidence from a wide range of fields. For example, advances in genetics and molecular biology have now shown how heredity actually works, as well as explained the nature of chance mutation (the source of the “variation” that Darwin noted). In fact, DNA now provides perhaps the single best piece of evidence supporting the theory of evolution. More closely related organisms turn out to have more DNA in common, meaning that the course of evolutionary change can actually be charted through genetic analysis.

As the National Academy of Sciences has noted, further evidence for evolutionary theory comes from such diverse arenas as the fossil record, comparative anatomy (which reveals structural similarities in related organisms, often called “homology”), species distribution (showing, for instance, that island species are often distinct from but closely related to mainland relatives), and embryology. With all of this interlocking evidence, the academy has declared the theory of evolution to be “the central unifying concept of biology.”
For a fast thumbnail explanation of the position of Evolution in science, this statement is hard to beat.

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