Williams College Biology Professor Luana Maroja sounds the alarm as she sees students challenging long-established science on political grounds:
The trouble began when we discussed the notion of heritability as it applies to human intelligence.
I asked students to think about the limitations of the data, which do not control for environmental differences, and explained that the raw numbers say nothing about whether observed differences are indeed “inborn”—that is, genetic.
There is, of course, a long history of charlatans who have cited dubious “science” as proof that certain racial and ethnic groups are genetically superior to others. My approach has been to teach students how to see through those efforts, by explaining how scientists understand heritability today, and by discussing how to interpret intelligence data—and how not to.
In class, though, some students argued instead that it is impossible to measure IQ in the first place, that IQ tests were invented to ostracize minority groups, or that IQ is not heritable at all. None of these arguments is true. In fact, IQ can certainly be measured, and it has some predictive value. While the score may not reflect satisfaction in life, it does correlate with academic success. And while IQ is very highly influenced by environmental differences, it also has a substantial heritable component; about 50 percent of the variation in measured intelligence among individuals in a population is based on variation in their genes. Even so, some students, without any evidence, started to deny the existence of heritability as a biological phenomenon.
Similar biological denialism exists about nearly any observed difference between human groups, including those between males and females. Unfortunately, students push back against these phenomena not by using scientific arguments, but by employing an a priori moral commitment to equality, anti-racism, and anti-sexism. They resort to denialism to protect themselves from having to confront a worldview they reject—that certain differences between groups may be based partly on biology.
She concludes that this has a chilling effect on education and research. It's pretty scary.