Cats can transfer a variety of infections, including MRSA, toxoplasmosis, ringworm, and hookworm. (credit: Kaldari) The ancestors of modern cats followed early farmers into Europe but weren't pets, according to a recent study. Nitrogen isotope ratios in the bones of six cats from Neolithic Poland suggest that these ancient cats hunted rodents that ate human farmers' crops, but they didn't eat quite the same diet as local people and their trusty domestic dogs.