POSTED 27 JAN 2005
Evolution under attack, again
As the mountain of evidence for evolution through natural selection continues growing, why are schools being asked to teach a supposed alternative called intelligent design?
As science gets ever more complicated, evolution stands out. For one thing, it's accepted as fundamental by virtually every working biologist, who are not an egregiously agreeable sort. And it's far simpler to understand than, say, string theory or gravitation.
Evolution through natural selection boils down to this: Organisms reproduce. Due to genetics, some offspring are better adapted to their environment, and they have more offspring. The genes of these winners become more common in the next generation. As changes accumulate, new species arise through this process of natural selection.
That's it. Essentially it's the same backbone laid down by Charles Darwin's 1859 book, "On the Origin of Species."
But ever since Darwin, evolution through natural selection has bothered some folks, who deem it a contradiction of the origin story in the Bible's chapter of Genesis.
And that hostility to evolution has now morphed into intelligent design. According to the Intelligent Design Network, "The theory of intelligent design (ID) holds that certain features of the universe and of living things are best explained by an intelligent cause rather than an undirected process such as natural selection. ID is thus a scientific disagreement with the core claim of evolutionary theory that the apparent design of living systems is an illusion." (Fifty-six words, two grave misconceptions: "That the apparent design of living systems is an illusion" is not "the core claim of evolutionary theory." Nor is evolution "an undirected process.")
Although "intelligent designer" sounds like another way to say "God," ID does not rely, at least overtly, on creationism's literal reading of the Bible: There is no mention of the seven days of creation, the garden of Eden, Adam and Eve, even Noah's flood.
So why are biologists alarmed? Because ID asks science to step back a couple of centuries and return the supernatural to science.
That's wrongheaded and unnecessary, say many scientists. Although the theory of evolution through natural selection is not complete, the fact of evolution -- massive changes through time -- is incontestable. We don't mingle with Neanderthals at the mall. Humans didn't scavenge the remains of T rex kills. All life began with single-celled organisms that arose roughly three billion years ago. Whales show many mammalian features, including breast feeding, a warm body, and a big brain. Why? Because they evolved from land-lubbing mammals.
The organizing principle
Biologists treasure evolution as the organizing principle of biology. As Russian-American biologist Theodosius Dobzhansky put it, "Nothing in biology makes sense except in the light of evolution."
Still, a near-majority of Americans tell pollsters that they believe the first humans were created less that 10,000 years ago, which follows Genesis more closely than science (a recent discovery in Africa dates the first human remains to 150,000 years ago). A majority of Americans claim to either believe in, or "lean toward," creationism, and even more believe both creationism and evolution should be taught in public schools, says Ronald Numbers, a historian of science at the University of Wisconsin-Madison.
In 2004, the never-ending struggle over evolution flared anew in public schools:
Cobb County, Ga. The school board required warning stickers on textbooks that cover evolution. A federal judge deemed the stickers an unconstitutional endorsement of religion, reasoning that the alternatives to evolution are rooted in the Bible. The board has appealed.
Grantsburg, Wis. On Dec. 10, the school board backtracked from an earlier mandate to teach intelligent design in science classes, stating, "Students shall be able to explain the scientific strengths and weaknesses of evolutionary theory. This policy does not call for the teaching of Creationism or Intelligent Design." Ironically, the focus on questioning evolution should please ID advocates, since the school board retreated to the very line that ID people are now advocating," says Numbers. The board did not question theories of gravitation or how the brain forms memories, which are less certain than evolution.
Dover, Pa. Parents of 11 students sued the school board over its effort to insert intelligent design into science classes. Local science teachers have already refused to read a "disclaimer" warning students that evolution is just a theory.
In the United States, during most of the 20th century, interpretations of Genesis were offered as alternative explanations for biological diversity. When legislatures or school boards proposed to teach this "creationism" in public-school classrooms, however courts defined it as religion, not science, and an infringement of the First Amendment separation of church and state.
But fair is fair. Advocates of ID demand a critical examination of evolution. What would we learn from a more critical consideration of ID?
Want some quick evolution facts? And even if you don't need them, maybe your school board does...
Megan Anderson, project assistant; Terry Devitt, editor; S.V. Medaris, designer/illustrator; David Tenenbaum, feature writer; Amy Toburen, content development executive