Cat Parasite Affects Everything We Feel and Do

theory that suggests that a clever cat parasite may alter human cultures on a massive scale. ... Toxoplasma gondii, has been transmitted indirectly from cats to roughly half the people on the planet, and it has been shown to affect human personalities in different ways. ... women who are infected with the parasite tend to be warm, outgoing and attentive to others, while infected men tend to be less intelligent and probably a bit boring. But both men and women who are infected are more prone to feeling guilty and insecure. ... Other researchers have linked the parasite to schizophrenia.... Can a common cat parasite account for part -- even if only a very small part -- of the cultural differences seen around the world?