Why is tech a predominately male interest?

There is an introduction thread on the Microsoft Tribe forum as with 74 replies no one has identified as female. This made me wonder why on average tech is more interesting to males than females. Obviously females use tech. For example, women in the US probably buy and use as many cellphones as men but men seem to be the ones more interested in things like pixel density, core processors, etc. Men and women drive cars but more men than women seem interested in taking those cars apart. Thoughts?