((This is a long debate, but it happens to touch on a subject I know very well, considering that my mother is a successful academic scientist and I was, for a very long time, intending to follow in her footsteps. I’m not going to rehash the arguments here about science being considered unfeminine and women being considered less intellectually able then men - others have done so better than I, and it is not an area where I can provide special insight. Although, to princess-munchkin, I will point out that there are plenty of women who do want to be scientists. Women are now over 50% of the Ph.D.-seeking graduate students in biology in the United States; in fact, although the proportion of female grad students has increased in recent years, the number of women being hired as junior faculty/researchers has not (see United States National Academy of Sciences (2007) Beyond Bias and Barriers: Fulfilling
the Potential of Women in Academic Science and Engineering (National Academies, Washington, DC) AND National Science Foundation (2009) Women, Minorities, and Persons with Disabilities in Science and Engineering (National Science Foundation, Arlington) for further reference on the topic), suggesting that the issue is not a lack of desire of women to participate in science and is more of an institutional bias against women, conscious or not. For conscious bias, I refer you to the remarks of the former Harvard president Larry Summers, who stated that, amongst other things, women fill top positions in many high-powered professions because they are less likely than men to work the long hours expected for advancement in these careers, and to explain that the gender gap in science, said “that in the special case of science and engineering, there are issues of intrinsic aptitude.”
An interesting study recently came out saying that woman with identical backgrounds and grades to their male counterparts were less likely to be mentored by established scientists, and were likely to receive worse recommendations. The full article is behind a paywall, but as a graduate student at a major university, I was able to access the full text; for those with an interest in reading the full article (perhaps to ensure my claims are correct and the study is well done), let me know, and I’ll see what I can do. Some of the figures and much of the gist of it are reproduced at this site, which also provides further analysis. Established scientists, faculty members at research universities, were given a profile of a student who wanted to work for them, with only the name differing between samples - one had a male name, one had a female name. The female was rated as significantly less competent and hireable, and the scientists were significantly less likely to mentor the female student. Furthermore, the starting salary for the female was on average $3000 per year lower than that offered to the male. This unconscious bias against females in science was present regardless of the gender of the evaluating scientists, i.e. female scientists did the exact same ratings as male scientists did regards competence, etc. This highlights the fact that even a strong female student may not get the mentoring that is absolutely essential to success in the sciences - I can verify that there is as much ‘who you know’ as ‘what you know’ involved in getting a postdoctoral position or junior faculty position in the biological sciences.
In addition to the discrepancy in mentoring, there is also more difficulty for a woman in science to get grants - funding for their research. Hiring and tenure decisions often revolve around the number and size of grants you have received, and if you don’t have money, you can’t do research. An analysis of granting practices showed that gender is a significant factor in whether or not a grant will be approved - that is, a grant submitted by a man is simply more likely to be accepted and funded than one submitted by a woman. It is a simple fact that if you cannot get funded, you cannot get tenure, and thus are in essence fired.
In conclusion, there are factors that strongly suggest that women are underrepresented in science not because of lack of desire to join science, nor because of overall incompetence in the sciences, but because of our cultural expectations of women. If you care to rebut this, please cite your sources, and don’t just proclaim that it’s silly to expect 50% of scientists to be women.))