Cat got your mind?

You can't make stuff like this up. Carl Zimmer writes on his blog about a parasite that infects rats and causes them to lose their fear of cats. Cui bono? The parasite, named Toxoplasma gondii, uses cats to complete its life cycle. So it evolved a way to bring cats and rats together--who needs match.com?

Here's the punch line: it infects humans too. There is some evidence that this parasite may also affect the way human brains function, including a possible link to schizophrenia. (This is at least one reason why pregnant women should avoid cat litter.)