Should Evolution Be Taught in Schools?
Once upon a time, creationists propounded a "creation model" of the origins of life on earth. Their story was based on a literal understanding of the book of Genesis. So, it claimed that the earth is quite young (merely a few thousand years old), that the fossil record was produced by a universal flood (remember Noah), and that, to all intents and purposes, plants and animals had remained the same since the first act of creation. The trouble with this proposal is that it was abandoned, for excellent reasons, by naturalists, virtually all of them extremely devout, decades before Charles Darwin wrote The Origin of Species.
The latest attempts to perpetuate the scientific ignorance of American schoolchildren come from people who have learned the lesson of the old failures. The neo-creos are far too savvy to commit themselves to any creation model. So, we should start by asking exactly what the children of Kansas are to be taught about the history of life.
They had better not be told that the earth is very young, since that would raise embarrassing questions about fundamental parts of physics and geology. Moreover, the worldwide order of fossils in the earth's crust shows that lots of different species have come and gone in the history of life on earth, and that, among the survivors, some are much older than others: Sharks have been around a lot longer than dolphins, conifers longer than deciduous trees. Once these basic points have been accepted, it's natural to ask whether new organisms were created to replace those that went extinct, or whether the later ones are related to the earlier ones.
The first point Darwin argued for in Origin was the universal relatedness of life. Recognizing that different species put the same anatomical structures to work in very different ways, he built a compelling case for the idea that the history of life is one of descent with modification. The forelimbs of moles, bats, whales, dogs, and human beings have a common arrangement of bones, but the moles have apparently modified this common structure for digging, the dogs for running, and so forth. Since Darwin, the evidence for these relationships has been stunningly confirmed as scientists have probed more deeply. The bands on the chromosomes of humans and chimpanzees are strikingly similar. The genetic data that are pouring in from contemporary sequencing support just the relationships that evolutionists have inferred. That's why there's no scientific controversy about common descent, the "fact of evolution." When pressed, even neo-creos (such as Michael Behe, the author of Darwin's Black Box) admit this (although, under other circumstances they're inclined to hedge and fudge).
There are three significant scientific results that are about as strongly confirmed as any piece of physics, chemistry, biology, or geology: The earth is very old, many different kinds of organisms have lived on the earth, and all living things are related in one genealogy. Any minimally educated person ought to know these things and to recognize the evidence for them. Why then is there any controversy?
Darwin's second big point was that the evolutionary changes that have occurred in the history of life were primarily due to natural selection. His successors have tried to understand how natural selection has operated to produce the diversity of living things. Some of their accounts are completely uncontroversial. But other proposals are hotly debated (there are, for example, rival views about why our hominid ancestors came to have bigger brains). No 20th-century biologist harbors doubts about the existence of natural selection. Some think particular claims about the operation of natural selection are wrong, and others believe that certain kinds of evolutionary change might be explained without invoking natural selection.
Enter the neo-creos. Scavenging the scientific literature, they take claims out of context and pretend that everything about evolution is controversial. By keeping in soft focus the basic points about the age of the earth, the succession of organisms, and the relatedness of living things, they preserve the hopes of the faithful that Genesis might be literally true. But it's all a big con. No literalist about the Bible ought to be satisfied, and the academic community ought to protest the sophistry of presenting interesting controversies about the causes of evolution as if they were serious issues about the fact of evolution.
Like all vigorous sciences, evolutionary biology faces open questions. The children of Kansas deserve to know what's genuinely unsettled (and why), just as they deserve to understand what has been established (and how). Neo-creos ought to begin by explaining just what their "creation model" is and exactly what it says about the age of the earth, the succession of organisms, and the relationships of living things. Tactical silences serve neither science nor religion.
Phillip E. Johnson is professor of law at the University of California, Berkeley. He is the author of four books on evolution and its philosophy, including Darwin on Trial (click here to buy the book and here for more on Johnson's work).Philip Kitcher is a professor of philosophy of science at Columbia and the author of Abusing Science: The Case Against Creationism (click here to buy the book).
Last week, the Kansas Board of Education voted to remove evolution from statewide guidelines and to allow individual schools to decide whether and how to include it in their curricula. Should evolution be taught in schools?
To confirmed believers in evolution, the question itself is upsetting. The Darwinian model of evolution is the cornerstone of modern biology. Critics say that failing to teach children about evolution would leave them ignorant and unprepared. (In this week's Time magazine, Stephen Jay Gould calls the Kansas decision the "latest episode in the long, sad history of American anti-intellectualism.") Furthermore, religious groups should not be allowed to edit the curricula of secular, First Amendment-protected schools to suit their particular beliefs.
Opponents of teaching evolution argue that it conflicts with faith-based belief in the origin of humankind. Teaching children to believe only in what is quantifiable and measurable crowds out their openness to religious faith. The Kansas creationists also argued that recent scientific research casts doubt on the validity of evolutionary theory, and thus opens the debate to religious explanations. "Creationism is as good a hypothesis as any for how the universe began," wrote the Topeka Capital-Journal in an editorial.
How do scientific critiques of evolution differ from faith-based ones? Are scientists just as stubborn as religious conservatives in their insistence on one explanation for the origin of humans? In 1987, the Supreme Court ruled that the teaching of "creation science" violated the separation of church and state. Does the Kansas approach do the same thing? And is evolution a theory or a fact?
This week, Phillip E. Johnson and Philip Kitcher discuss these and other issues.