By analysing 364 studies published in the last 25 years, Malin Ah-King, Andrew Barron and Marie Herberstein found that 49 percent only looked at male genitals, 8 percent only looked at female genitals, and 44 percent looked at both. There’s some variation: people who study spiders, snails and slugs are more likely to pay attention to female genitals. But in general, female sex organs—vaginas, bursas, cloacas, spermathecae and more—get a short shrift.
Sexism in science - Where are all the vaginas?