A similar fate befell a creationist stepchild, intelligent design, which holds that the universe is so intricate, so complex, that it has to be the handiwork of a master architect. While God is not explicitly identified as the designer, the implication is hard to miss. In a pivotal case, Kitzmiller v. Dover Area School District, a federal judge in Pennsylvania ruled in 2005 that introducing intelligent design in biology classes as an alternative to evolution unconstitutionally advanced “a particular version of Christianity.” At heart, the judge said, intelligent design was “creationism relabeled.”

And so, once more, the anti-Darwinists were forced to evolve. What emerged were state laws with descriptions like the “science education act” and the “academic freedom act.” One of the earliest and most successful of these endeavors, the Louisiana Science Education Act of 2008, carried echoes of a “wedge strategy” advocated by the Discovery Institute — a step-by-step program to “reverse the stifling dominance of the materialist worldview and to replace it with a science consonant with Christian and theistic convictions.”

The Louisiana law permits public schoolteachers to use materials critical of established scientific thought, with “evolution, the origins of life, global warming and human cloning” singled out as targets. No blatant advocacy of creationism or intelligent design is authorized. But those concepts make their way into classrooms all the same, as a means of fostering “critical thinking skills, logical analysis, and open and objective discussion of scientific theories.”

In other words, it’s O.K. in Louisiana for schools to, as some put it, “teach the controversy.”

“Often the theories that are presented as solid are not as solid as they’re presented,” Stephen Meyer, director of the Discovery Institute’s Center for Science and Culture, told Retro Report.

Georgia Purdom, a molecular geneticist who is also a creationist, offered much the same view. “I am a scientist, and I have looked at the science, and I see that it confirms God’s word,” Dr. Purdom said. “But I would also then like to be able to teach evolution, what the evolutionists believe, and then the problems with that. Because there can only be one truth. They both cannot be true.”

As more mainstream scientists see it, Louisiana has disingenuously slipped creationism into schools through a back door (with perhaps an added advantage of being able to cast the law’s opponents as nothing more than intellectually intolerant of countervailing thought). There is another concern, said Kenneth R. Miller, a molecular biologist at Brown University. A new generation, he said, is being taught that “the scientific method and the scientific community is not to be trusted.”

Thus far, the Louisiana law is proving to be bulletproof. No court case has been brought against it, even if Dr. Miller says somewhat dismissively that this is only because “the First Amendment protects you against imposition of religious ideas in the public schools — it doesn’t protect you against the introduction of stupid ideas.”

And Louisiana does not stand alone. Tennessee, home of the Scopes trial, passed a comparable law in 2012. Efforts along the same line have been tried in other states, including Mississippi, Alabama, Indiana, South Dakota, Missouri, Florida and Oklahoma.

Those legislative moves, in the main, have had limited success. But given the prevailing political climate, the anti-evolution camp may have reason to believe that the wind is at its back and more triumphs lie ahead. If it wishes, it could borrow another line from that old song. This one says, “Evolution mama, don’t you think you got me up a tree.”

CLYDE HABERMAN, a regular contributor to Retro Report, has been a reporter, columnist and editorial writer for The New York Times, where he spent nearly 13 years based in Tokyo, Rome and Jerusalem. Subscribe to our newsletter here and follow us on Twitter @RetroReport.

This article first appeared in The New York Times.