With a screech too high-pitched for the human ear to detect, the tiny one-ounce vampire bat launches itself into air with a giant leap and swoops onto unsuspecting prey. The vampire bat is the only one of 1,000 bat species to feed on animal blood -- usually from horses, pigs, and cows. Feeling queasy? Heat sensors on its nose help the bat zero in on veins close to the skin, where it drinks about two tablespoons of blood a day.
Fortunately, vampire bats inhabit only Central and South America, roosting in caves, trees, and deserted buildings.