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

CNN has an interesting article on social isolation in the US. Despite being a modern country of nearly 300 million that prides itself on its technological connectivity, this nation has an increasing number of lonely people. Chronic loneliness can be a serious condition, and is a major risk factor for depression, high blood pressure, herat diseases, obesity and stroke.

Loneliness is the anxiety that you do not matter at all.

~ Joyce Huggest

Technorati Tags: loneliness, social isolation