Common vampire bats need to feed on blood almost daily to avoid starvation. They are are not the fearsome, blood-sucking creatures portrayed in the movies, however, but rather ordinary-looking, medium-sized bats with a highly evolved feeding method. They don't actually suck blood, but lap it up from cuts made by their razor-sharp incisors. A chemical in the saliva stops the victim's blood clotting and numbs the wound. Vampire bats live in large colonies in Central and South America where they feed mostly from the abundant livestock.

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