The debate about why certain online communities attract a majority of men while others attract a majority of women often seems to focus on the following:

* Debate/discussion versus chat/socialisation sites * Whether the "major topics" (think: top 10 subreddits, etc.) are male-focussed or female-focussed * Critical mass of users of a particular gender (early adopters) * Whether or not anonymity is allowed or encouraged * What controls are in place to report inappropriate content

I'd like to suggest an alternative (partial) explanation. It's not an opinion that I hold, but it's a possibility that perhaps should be considered:

Perhaps men and women are naturally inclined towards single-sex communities. This is linked to the "critical mass" idea, above, but with the additional conclusion that it is even harder to reverse the trend. If we treat services like Foursquare as outliers, we could quickly find evidence for the hypothesis that, in choosing a "space" online, men look for places where men are, and women look for places where women are.

Of course, there are exceptions: there always are. But if only 50% of men and 50% of women worked by this criteria, we'd expect to see communties with about a 75%/25% split (and, in fact, we'd probably see a variance from that because of the number and size of those communities, of course).

Is one of the things that attracts men, more than women, to Hubski, the fact that it is predominantly male, and not female?

I'm sure that a sociologist or an anthropologist can throw some weight at this, but isn't it the case that for a large amount of human history, societies have biased men to spend social time with men, and women to spend social time with women. We're getting better at it, in Western society, I think, but the historical bias is still there. Think back to your school days and whether you had more same-sex friends or opposite-sex friends: there'll be outliers, of course, but most people will say that they had more same-sex friends. Why?

It's possible that the root of the gender divide in our online communities shares the same root as that in our offline communities. Perhaps we shouldn't be asking "Why are there no women on Reddit?" and "Why are there no women on Pinterest?", and instead ask "Why are men generally inclined to socialise with other men and women with other women?"

Perhaps the answer's sociological or psychological: perhaps we're conditioned this way by millennia of historical sexism. Or perhaps it's biological? In the same way as other species have clear gender-based roles (male lions either live with many females, or completely alone, for example), maybe we humans have our own similar tendencies? But whatever the cause, it's possible that to answer the question we need to cast our nets wider than "online communities".