Here’s a fascinating story on how the parasite Toxoplasma gondii could have influenced (partly) the manner in which people from different parts of the world developed along different cultural lines.
When the parasite infects the brains of rats and mice, it alters their behavior, making them more reckless than normal–reckless enough that they don’t avoid cats the way good sense would dictate. As a result, they’re devoured, at which point the micro-organisms are able to reproduce–something they can only do in felines…
Humans eat toxoplasma too, in such things as unwashed vegetables …
… But while we don’t go running out to find a mountain lion or other big cat to play with, it could well be that humans experience subtler behavioral changes than a rat would–a mild increase in the tendency to be adventurous, say. And because toxoplasma infection is actually quite common in humans, and varies from one region to another–about a third of Americans show antibodies to the parasite, but in Brazil the number rises to nearly 70%, while in South Korea it’s under 5%.
Wierd ! But as the Time writer put it,
… it’s a little horrifying that cultural diversity could be a symptom of parassitic infection.
Technorati Tags: Toxoplasma gondii, culture
1 Comment
March 3, 2007 at 12:38 pm
Interesting statistics