Come September, science textbooks across Turkey will be missing a pretty fundamental chapter.

That’s to say, all mentions of evolution will be removed from the country’s high school curriculum because the theory is too “controversial,” a government official announced this week.

When it comes to the debate about evolution, the government fears that their students, “don’t have the necessary scientific background and information-based context needed to comprehend,” said Alpaslan Durmus, the chairman of the Education Ministry’s Education and Discipline Board, in a video posted on the ministry’s website.

The move is part of what critics are calling a creeping strain of ultra-conservatism under President Recep Tayyip Erdogan in what was once a secular country.

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Angry secularists have come forward, arguing that the new curriculum would place Turkey in the same category as Saudi Arabia, where this particular science lesson is also ignored.

“The last crumbs of secular scientific education have been removed,” Feray Aytekin Aydogan, the head of Egitim-Sen, a union of secular-minded teachers, told The New York Times.

“Forget high school, you can comfortably explain it in preschool,” she said. “This is one of the basic topics you need to understand living beings, life and nature.”

This curriculum change is the latest in a series of moves geared at replacing secular ideas with religious ones.  

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Over the past five years, the government has slowly pushed aside the ideas of Mustafa Kemal Ataturk, founder of contemporary Turkey, who established a staunchly secular society in 1923. At the same time, it’s increased the number of religious schools and, in 2013, removed a ban on headscarves in universities, arguing that it discriminated against religious Muslims.

Some argue, however, that Turkey is still not a deeply Islamic society.

“Much of the public visibility of Islam doesn’t necessarily have a very deep basis,” argued Kerem Oktem, the author of “Angry Nation,” a book about the history of modern Turkey.

But as the education system heads in its newfound direction, a future without a basic introduction to evolution is guaranteed for the roughly 14 million children enrolled in primary and secondary schools in Turkey.