When a healthy rat smells a cat, it flees. But rats infected with the Toxoplasma brain parasite actually follow cat odors, often presumably to their doom, red in tooth and claw. Now researchers have found out exactly what’s going on in the rat’s infected brain—it’s in love. The study is in the journal Public Library of Science ONE. [Patrick K. House, Ajai Vyas and Robert Sapolsky, Predator Cat Odors Activate Sexual Arousal Pathways in Brains of Toxoplasma gondii Infected Rats]
That Toxo-infected rats approach cats has long been a well-known example of a parasite manipulating the behavior of its mammalian host. The protozoan needs to be in a cat’s intestine to reproduce. It then gets pooped out and has to find its way into another cat to continue its fabulous
