If you don't see it, you're part of the problem.

This post by Female Science Professor and some of the comments to this post compel me to point out (quite unnecessarily) that sexism is rampant in the Academy. We females aren't just whiny and paranoid, Gentlemen. If a significant fraction of the graduate students in your field are women but only a few of your colleagues are women, then there's a problem and you are very likely contributing to it.

The worst offenders are often the nicest guys. They have no idea they are being sexist, believe, in fact, that they aren't being sexist, and so the problem persists.

Here are only a few of my recent observations:

• Men have important discussions and sometimes make administrative decisions with male colleagues while standing at the urinals. There's rarely more than one woman in the restroom at a time in my department and at my conferences; there are too few of us.
• Talks given by women are more frequently interrupted, often with irrelevant or tangential comments. At my recent conference presentation, a man interrupted my first slide to ask a procedural question about Pap smears.
• Women who attempt to ask questions about or comment on talks usually raise their hands so the moderator can call on them. Men frequently fail to do this, and even when the moderator does call on a woman, men sitting nearby assume that the moderator called on them and will talk over her. I have seen a woman fight back by being just as aggressive and rude, and even pointing out to the audience that it was her turn; she was labeled oversensitive and bitchy.
• Women are frequently not told of nor asked to contribute to special journal issues or special collections, even when the topics are directly related to their research. I am on the editorial board of a journal, and only recently found out that several special issues are in press. The decision to release these special issues was made by a subset of the men on the board without consulting the board as a whole; no work by women is represented in these issues.
  
• Seminal papers authored by women are overlooked until that line of work is cited by men. Then it is the men's papers that are cited; the original work is forgotten. I can name at least three areas in my field where this has happened, and one of the areas is mine (keep reading).
• I initiated a now important and popular line of research approximately a decade ago. A man (my post-doc advisor) decided to do research in this area, and conducted a series of federally-funded workshops here at LSU. I was not invited to participate (told, in fact, that my participation was not welcome), and was not told about them until the day before they began.

You can say that many of these instances are just examples of academics being shitty to each other. However, this crap doesn't happen to men. Give me one time that a man's talk was interrupted by a woman asking about a prostate exam, or one time that a man's seminal paper was overlooked in favor of a woman's later work.