Theodore Hill, a retired professor of mathematics at Georgia Tech, claims that activists successfully pressured the New York Journal of Mathematics to delete an article he had written for the academic journal because it considered a politically incorrect subject: the achievement gap between men and women at very high levels of human intelligence.
The Greater Male Variability Hypothesis, first proposed by Charles Darwin, suggests that there are more men than women at both the bottom and the very top of the distribution for intelligence scores. More men than woman are Nobel Prize winners and chess grand champions, and more men than women are homeless, unemployed, and in prison. Men as a group express greater variability in aptitude and ability. This difference, of course, need not be innate—it could be the case that social custom and pressure has punished women for falling anywhere outside the norm.
Writing for Quillette, Hill says that he and a co-author came up with a theoretical model that would help explain the gap, then attempted to publish a paper about their work in Mathematical Intelligencer. The paper was accepted, though the topic is controversial: Larry Summers resigned as president of Harvard University in part due to criticism he received for broaching the subject of variability at an academic conference.