‘The enormous difference between male and female sexual behaviour may be explained, in animals at least, by a tiny organ in the nose rather than by any gender difference in brain circuitry. [..]
In a study published by the British journal Nature, the team engineered female lab mice so that the rodents lacked a gene called TRPC2, effectively short-circuiting the so-called vomeronasal organ. [..]
The findings are important, because they amount to a massive blow to those who for decades have looked for underlying differences in brain structure to explain why sexual behaviour between males and females is so dissimilar.
The answer appears to be this: in the mice at least, there is no difference. The hard-wiring of the brains is the same.
“In the big picture, it suggests that the female brain has a perfectly functional male behaviour circuit” which is repressed by signals from the vomeronasal organ, Professor Dulac says.’