How is sexism unknowingly perpetrated in academia? Some sexism is obvious, blatant, and/or deliberate. Fortunately, my understanding is that this kind of sexism is mostly a thing of the past.

However, female colleagues have told me that more "benign", but still harmful, sexism is still very prevalent in academia. In particular, I've heard that implicit assumptions that women are less capable, or more inclined to be teachers than researchers, are distressingly common. As a mathematician, the results are distressingly obvious: most math departments are overwhelmingly male.

What are some ways in which sexism is unknowingly perpetrated by well-meaning people, in academia in particular? And how can those of us who are well-meaning make sure to avoid doing so?
And how can those of us who are well-meaning make sure to avoid doing so?


If you see something, say something.

You're correct that blatant sexism is mostly gone.  I'm a female computer engineer, and I have never been told that I can't do the job because I'm female.  What remains is "death by a thousand paper cuts" sexism.  For example, I was recently at a conference, and the small group I was in was discussing one of the presentations.  An older professor in the group remarked that the presentation was particularly good because the presenter was beautiful and wearing tight clothes.  Nobody called him on it: after all, he was trying to give her a compliment, mentioning it would be rude, he's older and things were different then, and so on.  And it's hard to blame them, because if that were the only sexist comment I heard that day, it wouldn't be such a big deal.  But shortly after that, someone jokingly said I should marry my PhD supervisor.  Then someone said a new tool is so user friendly that "even your mother could use it".

Each of these incidents on its own is fairly mild: most people probably don't even realize they're saying something exclusionary.  Unfortunately, if you're a woman, each one reminds you that you don't belong, so the cumulative effect is very discouraging.  However, if you correct every person who says something mildly sexist, you get a reputation as a bra-burning feminazi.  As a result, most women keep quiet, or only point out the particularly insensitive comments.  It would make an enormous difference if other men would call out the ones who make inappropriate comments.  You don't have to be dramatic or rude about it, but a quiet "I don't think that's appropriate" would take a lot of the burden off women.  And naturally, you can try to be more aware of the things you say to make sure you aren't accidentally discouraging women.  A lot of sexist ideas are so deeply ingrained that otherwise fair and open minded people will say them without a second thought (like the "even your mother" comment).

I don't want to downplay the other valuable things you can do, such as volunteering at math/science camps for girls, but if enough men followed this rule -- even part time -- 80% of the sexism I encounter would disappear. To modify Edmund Burke's quote a bit,


  All that is necessary for sexism to triumph is for good men to do nothing.


June 27, 2014: After a year of comment trolls, I think it's time to add a point about men's rights activists.  The key mistake that MRAs make is treating rights as a zero-sum game.  The fact is, gender stereotypes hurt everyone.  They hurt women who want to be engineers; they hurt men who want to be nurses.  They hurt women who don't want to have children; they hurt men who want to be stay-at-home dads.  

Sometimes, these stereotypes result in a disadvantage for men.  For example, Doug Spoonwood points out that American men have to register with the selective service system to get student loans, while American women do not.  MRAs point to these cases and try to claim that feminism oppresses men.  This is, at best, willfully ignorant: all these inequalities come from the same outdated beliefs and stereotypes, which feminism opposes by definition.  The fact that these cases exist just indicates that gender equality is not a solved problem.  (Women in the American military were not allowed to be in units tasked with direct combat until 2013.)

My answer discusses a woman's point of view because that's what I know and that's what the question asked about.  I would be thrilled if a man in a predominantly female field added an answer discussing his experience.