Interesting figures, and they explain a lot.
I had arrived at the same conclusions from purely anecdotal evidence, its nice to see someone has compiled real statistics on the subject. A reasonable preliminary conclusion would be that the psychological makeup of liberals tends to attract them into the sciences. I doubt if its the other way around. I'd like to see the same figures compiled for lawyers.
At any rate, these numbers go a long way towards explaining the anti-science bias of Conservatives, as well as their general mistrust of all intellectuals and academics. They know people trained in critical thinking are not as likely to find their positions and opinions to be acceptable.
Bazinga! 8)