[Dog]

Rats infected with the parasite Toxoplasma seem to lose their fear of cats -- or at least cat urine. Now researchers have discovered the brains of those infected, fearless male rats show activity in the region that normally triggers a mating response when encountering a female rat. But that does not mean it's love, as Toxoplasma just wants the rat to be eaten by a cat, so the parasite can reproduce in the cat's intestines.

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