This needs to be said at the outset: The concept of "intelligent design," as opposed to Darwinian evolution, is based either on ignorance or outright fraud.

Florida's public schools are under increasing pressure to include "intelligent design" in their biology classes, and offer the belief as an alternative to Darwin's concept of evolution based on natural selection.

The Florida Department of Education recently announced the appointment of Ms. Cheri Pierson Yecke as chancellor for kindergarten through grade 12. Ms. Yecke, formerly a Minnesota education commissioner, is a known proponent of "intelligent design."

Just what is "intelligent design?"

On the surface, ID (as we'll abbreviate it from here on) pretends to be an hypothesis for explaining how biology works, and how the human race came into being. Its central idea is that we humans are so complex that our existence cannot be explained by the workings of physics and chemistry; there must be some intelligent designer who produced us in all our complex splendor.

Who is this intelligent designer? He (or she, or it) would have to be a supernatural being, far beyond our own capabilities, to have created us. And since ID presents itself as an alternative to evolution, then the ID position is decidedly against the notion that we evolved out of earlier creatures. We must have been created separately.

With one fell swoop, as it were, ID takes us back to the 1850s, before Darwin, and offers us a world in which an unknowable designer created us separate and apart from all the other animals, plants, and simpler organisms of our world.

ID is nothing more than a straw man for the concept of creationism, the idea that we humans were created by the God of the Old Testament, just as it says in Genesis.

That's where the fraud comes in. ID is not a scientific theory: it's a stalking horse for fundamentalist religion.

ID offers not the faintest scintilla of evidence to support its claims. By saying that we were designed by an intelligent creator, ID bypasses the idea of explaining anything. It is the antithesis of science. Science seeks to understand, to ask questions and find answers, to uncover new knowledge.

ID is not interested in new knowledge. We were created by You-Know-Who. Period. End of discussion.

All right, then, what is Darwin's concept of evolution through natural selection all about, and why are religious fundamentalists so anxious to get it tossed out of the school curriculum?

At heart, Darwinian evolution is a simple idea. Organisms face a constant struggle for survival. The environment in which we (and all other organisms) exist can be harsh, fatally so. The individuals who are best suited to survive in their environment have more offspring than individuals who die early. That is natural selection.

For example, the dinosaurs were lords of the Earth for more than 100 million years. But eventually they were faced with an abrupt and very severe change in their environment: a large meteoroid crashed to the Earth and caused a drastic shift in the global climate. More than half of all the species on Earth became extinct, unable to cope with the sudden change.

(Note well: If a similar meteoroid hit the Earth tomorrow, our civilization — and probably our whole species — would also get wiped out. We don't yet have the technology to avert such a catastrophe.)

All right, environments change and species go extinct. A wooly mammoth is ideally suited for living in an ice age, but when the climate warms up, the mammoth disappears forever.

However, some species or individuals have bodily features that help them to survive a change in the environment. A bald mammoth thrives in a warmer climate, perhaps. Eventually, his descendants become what we know today as elephants. Certain species of dinosaur developed wings and feathers, even before the killer meteoroid impact, and evolved over the long course of generations into the birds.

Darwin's theory does not deny the existence of God. It says nothing about God. But it does show how the creatures of this world could have come into being, in all their complexity and beauty, without needing an intelligent designer.

What bothers religious believers most, I suspect, is that Darwin showed how human beings are related to other creatures. We were not designed specially and apart from the others. We have cousins, the primate apes, and more distant relatives. We carry in our cells many of the same genes found in the cells of chimps, and mice, and even yeast.

Ah, say the anti-evolutionists, but Darwin's concept is "only a theory." It's not proven fact.

Well, yes it is proven fact. The evidence supporting evolution is mountainous, ranging from fossils of bygone creatures to the strands of DNA in the cells of every organism on Earth. There is more evidence for evolution in a single drawer of any natural history museum than in all the phony pronouncements and deliberate misstatements of those who desperately want to see ID and old-fashioned religion replace evolution in our children's schools.

But there's that word, "theory." To scientists, theory is high praise. A theory is a unifying idea that brings together many different observations and make sense of them. Theories point the way to new investigations and new discoveries, just as Einstein's theory of relativity led to the invention of the laser — and the atomic bomb.

Darwin was not trying to disprove the existence of God. Religious believers should consider that Darwin was showing the steps that God took in bringing us into existence. There is no need for ID, nor for a schism between science and faith.

But intolerance is an ugly thing, and the backers of ID want to drive evolution out of the classroom. Imagine how they would react if scientists started pressuring governments to stop giving tax breaks to churches.

Naples resident Ben Bova is the author of more than 100 books, including the novel "Mercury," the latest entry in his acclaimed Grand Tour series. Dr. Bova's Web site address is www.benbova.net.