So... as referenced to yesterday, I was doing some research. I published the results on meta at https://meta.wikimedia.org/wiki/Research:Men_of_Quora_use_Wikipedia_to_get_t... . The gist of it appears to be that women on Quora are less likely to link to Wikipedia than their male counterparts. I am not completely sure what the reasons for this are, but some of the research done by others appears to hint around the edges at possible causes... though I am not sure how much they explain this. (Is this a Wikipedia issue or a Quora issue?)
If you're interested in some research looking at the gender gap on another site, http://statisticsforfun.quora.com/ is where a fair bit of my Quora research can be found. It is interesting, especially given that Quora does some of the things people say Wikipedia should do to fix its problems.
Sincerely, Laura Hale