Where My Girls At?

I and some of my more risk-seeking associates will be spending part of next summer in a car race from London to Mongolia. The whole this is a charity fund raiser and more of an adventure than an actual race (the goal is to finish in the car you started with, something which roughly one third of the cars do). This is going to be fun. However, with the exception of my sister, all of my teammates are men. This is not deliberate; I invited all of my friends, but it was only men that were interested. There are four female members of my polo club, and maybe five female elephant polo players (I am one of two female captains). The only female helicopter pilot I know only signed up for classes because she was involved in some weird effort to stalk me/copy my life at the time My office (IT) is mostly men as well.

Which makes me ask, where are all the women? My female friends are a generally cool group, and are certainly well-traveled, well-educated and generally un-timid, but they just aren't interested in such "outgoing" challenges. I'm not a tomboy, and get along in everything else, but when it comes to adventures, its mostly the men who are interested. Why is this? Some of this is just plain sexism or mixed up gender roles - in elephant polo for example the women come, but cheer or serve as "stick chicks." They get a ladies game at the end but not even those ladies think of playing on the team itself, they just think how nice it is that they also had the chance to play (and it is). But a lot of it doesn't make sense.

Any ideas?