“Dominated By Men?”
August 24, 2006
From Microbiology Bites ( a really cool blog)- ” that brings you the latest news about microbiology in a form that everyone can understand.”
Supposedly, a quarter of the world’s population is infected with Toxoplasma gondii, a long-lived and common brain parasite. The normal host for this organism is the domestic cat, so maybe it’s not so surprising that human infections are also common.
What is surprising is that the parasite is capable of subtle manipulation of its host. Humans become infected by eating infected meat, or more usually by direct contact with soil or cat faeces. However, humans are dead-end hosts as far as the parasite is concerned (no transmission), and it usually only causes mild flu-like symptoms, although severe disease can occur in an unborn foetus or immunocompromised patients. In this situation, the parasite becomes dormant in the brain and other tissues. But that’s not the end of the story!
Can an infectious disease indirectly alter human culture through its effects on personality? People infected with T. gondii experience long-term personality changes:
- Women become more intelligent, warm, outgoing, attentive to others, kindly, easy-going.
- Men show lower intelligence, novelty-seeking and bad tempered.
- Both infected men and women have higher levels of guilt-proneness.
Now a recent paper suggests that male domination of societies worldwide may owe much to T. gondii infection Kevin D. Lafferty, Proceedings of the Royal Society B: Biological Sciences , 01 Aug 2006). C’mon girls, tell me that you knew that all the time!