Discriminations quotes extensively from a Chronicle of Higher Education essay (paid subscribers only) on why the battle on campuses is a war over masculinity more than anything else.

In one corner reside the standard-bearers of academic machismo: the hard-nosed male professors of math and physics, economics and politics, as well as those stout-hearted men in English, history, and philosophy who have fought the good fight. By their side stand several equally stalwart women -- the tough-minded, the blunt-spoken, the widely published; in short, the women "with balls." In the other corner reside "those people": the politically outspoken women -- feminists, multiculturalists, and the like -- in French and Spanish, psychology and anthropology, environmental and gender studies, who have dragged the campus into its current morass of soft, mushy interdisciplinarity (read "undisciplinarity") and -- workshops. And by their side stand (however limply) those emasculated men who occupy the bottom rung on [his friend�s] ladder of academic virility.

UPDATE: Cold Spring Shops adds:

My impression is that the disciplines the essayist characterized as the "harder-nosed" are those with less imbalance between Ph.D. production and Ph.D. hiring, higher starting salaries, and more difficulty attracting U.S. born graduate students. Thus a problem: why are the disciplines that by any market test would suffer from overcapacity, if my impressions are supported by any evidence, calling the shots in the academy?

Because they become administrators! And lest Stephen think that begs the question, they become administrators because it's the only way for them to move up financially. The hard-nosers largely teach in areas with ample private-market opportunities.