Well, as bateleur clearly knows something about the dark arts of statistomancy, I'm not even going to attempt to reach any mathematical conclusions, but it is at the very least curious that the number of first-borns is as high (relatively) as it is. It sounds like the sort of subject that Robert "Quirkology" Wiseman would research.

It would be quite interesting to know what the demographic splits are in this context, not just in terms of geekiest, but in terms of the sorts of jobs people do, academic achievements, interests, social groups. Perhaps those data have been collected by someone already...