Every now and then a science article will throw up something that I think is brilliant. An article in today’s Seed, entitled The Wiring of Desire, contained one such nugget.
After discussing how temperature affects sexual selection in developing gecko embryos, and how it also affects later behaviour, the author goes on to mention similar effects on other species:It turns out that an embryo’s environment has similarly powerful effects in other species. Mice, for example, give birth to more than one pup at once — and the behavior of adult mice is affected by whom they were next to in the womb. A female who was between two sisters is more docile as an adult, and males tend to find her more attractive than other females. She is also more likely to be attacked if she rejects a male’s advances. A female who was sandwiched between two brothers will be more aggressive—and less attractive to males.I just like it because it illustrates the fluid nature of everything in nature. It’s not simply a case of different, precisely controlled, doses of testosterone for male and female, but a general increase of testosterone in the area around embryonic males which then also raises levels in any surrounding females.
