Hormone and brain development

[andrewducker]

I've ended up with a whole sprawling mass of links for this one, each with interesting information. I started with a New Scientist article which contained:

Levels of hormone exposure in the womb helps determine which academic discipline researchers work in, a new study suggests. Perhaps surprisingly, a "female" pattern of exposure was common in scientists, while a "male" pattern dominated in the social sciences.

The survey compared the length of people's index (first) fingers with their ring (third) fingers. This comparison is thought to indicate prenatal sex hormone exposure, probably because some developmental genes control the formation of both the reproductive system and the digits.

Hormone levels also appear to predict which discipline researchers work in. Staff in the departments of chemistry, computer science, mathematics and physics all had average ratios of over 0.995 - close to the female average - despite 81% of those subjects being male.

In contrast, the staff of the social science departments of economics, education, management, social and policy sciences had an average ratio below 0.98, the male average, despite only 66% of this sample being male.

I'd heard the finger-length one before - it turns out to be links to the HOX genes, which regulate body shape - these are the same throughout everything from fruit-flys to people. Some more digging turned up a link between this and sporting ability, links with depression and also seems to affect sexuality. What's interesting is that the level of prenatal testosterone seems to be affected by several things, including the number of older brothers you have - older sisters seem not to affect testosterone levels, but the womb does seem to be affected in this way by boys gestating in it.

Of course, this is all just tendencies - there's nothing saying what any individual will do. Still, interesting stuff.

Comments

[cheekbones3.livejournal.com]

Hmm - I'm pretty much a scientist, and my fingers look to be closer to the female configuration.

[andrewducker]

Ditto. And ditto.

[heron61.livejournal.com]

Yet another study with microscopic sample sizes that confirms popular prejudices about gender traits. I'm deeply unimpressed, especially since I ran into another finger-length study regarding sexual preference that I'm fairly certain was done by the same people and had one of the shoddiest methodologies I've ever seen: going up to people who "looked like gays or lesbians" (ie a sample with ludicrously lax sampling criteria) at a gay pride event and measuring their fingers on the spot (with all of the inaccuracies that doing such measurements in a crowded public setting).

I continue to be amazed at the lack of competence in almost all studies relating to both gender and sexual preference studies.