<p>Are these two linked? On the one hand, Testosterone injections seem to improve the ability of persons to solve Physics problems in certain double-blind studies. On the other, the most intelligent males are stereotypically among the least sexually potent, perhaps insofar as they might be presumed to have smaller than average members, hence females' lack of interest in nerds.</p>
<p>Perhaps it might be a bit of correlation going in both directions, with Testosterone improving IQ but worsening memory? This would explain female success in Memorization(GPA)-driven majors such as accounting and biology, and male success in IQ-driven (and aptitude/work driven, aptitude being a function of IQ) majors such as engineering.</p>