Keep your parasites to yourself, kitty.

On Edge, Stanford neuroscientist Robert Sapolsky has a fascinating examination of how parasites can affect the behavior of their hosts, even mammalian hosts like your or I. In particular, he discusses the effects of Toxoplasma or Toxo. This parasite, which grows in the stomachs of cats, can play havoc with the thought process of rats that come into contact with cat feces, but it also seems to be linked to schizophrenia and reckless behavior in humans. Doctors have often reported high levels of Toxo in the organs of people who’ve driven recklessly and gotten into motorcycle and automobile accidents. Sapolsky worries that Toxo’s knack for obliterating rational decision making could be used for nefarious means through bioengineering. An excerpt:

“You want to know something utterly terrifying? Here’s something terrifying and not surprising. Folks who know about Toxo and its affect on behavior are in the U.S. military. They’re interested in Toxo. They’re officially intrigued. And I would think they would be intrigued, studying a parasite that makes mammals perhaps do things that everything in their fiber normally tells them not to because it’s dangerous and ridiculous and stupid and don’t do it. But suddenly with this parasite on board, the mammal is a little bit more likely to go and do it. Who knows? But they are aware of Toxo.”

Read the full article.