The latest struggle over the teaching of evolution in the public schools of Kansas provides striking evidence that evolution is occurring right before our eyes. Every time the critics of Darwinism lose a battle over reshaping the teaching of biology, they evolve into a new form, armed with arguments that sound progressively more benign, while remaining as dangerous as ever.

Students of these battles will recall that in 1999 the Kansas Board of Education, frustrated that the Supreme Court had made it impossible to force creationism into the science curriculum, took the opposite tack and eliminated all mention of evolution from the statewide science standards. That madness was reversed in 2001 after an appalled electorate had rejected several of the conservative board members responsible for the travesty.

Meanwhile, Darwin's critics around the country began pushing a new theory - known as intelligent design - that did not mention God, but simply argued that life is too complex to be explained by the theory of evolution, hence there must be an intelligent designer behind it all.

The political popularity of that theory will be tested today in a school board primary election in Dover, Pa., where the schools require that students be made aware of intelligent design as an alternative to Darwinism. The race pits those who voted last year for that rule against those who oppose it.

Now the anti-evolution campaigners in Kansas, who again have a state school board majority, have scrubbed things even cleaner. They insist that they are not even trying to incorporate intelligent design into state science standards - that all they want is a critical analysis of supposed weaknesses in the theory of evolution. That may be less innocuous than it seems. Although the chief critics say they do not seek to require the teaching of intelligent design, they add the qualifier "at this point in time." Once their foot is in the door, the way will be open.

The state science standards in Kansas are up for revision this year, and a committee of scientists and educators has proposed standards that enshrine evolution as a central concept of modern biology. The ruckus comes about because a committee minority, led by intelligent-design proponents, has issued its own proposals calling for more emphasis on the limitations of evolution theory and the evidence supposedly contradicting it. The minority even seeks to change the definition of science in a way that appears to leave room for supernatural explanations of the origin and evolution of life, not just natural explanations, the usual domain of science.

The fact that all this is wildly inappropriate for a public school curriculum does not in any way suggest that teachers are being forced to take sides against those who feel that the evolution of humanity, in one way or another, was the work of an all-powerful deity. Many empirical scientists believe just that, but also understand that theories about how God interacts with the world are beyond the scope of their discipline.

The Kansas board, which held one-sided hearings this month that were boycotted by mainstream scientists on the grounds that the outcome was preordained, is expected to vote on the standards this summer. One can only hope that the members will come to their senses first.