vampire bat
A small bat that drinks blood from sleeping animals.
A vampire bat is a small bat that feeds on blood, mostly from sleeping animals like cattle, horses, or pigs. Unlike the fictional vampires in movies and books, real vampire bats don't suck blood through fangs. Instead, they use their razor-sharp teeth to make a tiny cut in an animal's skin (usually while it sleeps) and then lap up the blood with their tongues, like a cat drinking milk. Special chemicals in their saliva keep the blood from clotting, so it flows freely.
Only three species of vampire bats exist, all living in Central and South America. They're actually quite small, about the size of an adult's thumb, with wingspans around seven inches. Despite their creepy reputation, vampire bats rarely bite humans and typically take only about a tablespoon of blood from their animal hosts, not enough to seriously harm them.
Vampire bats have evolved remarkable abilities: they can detect the warmth of blood vessels using special sensors in their noses, walk and even hop on the ground using their wings and legs (unusual for bats), and share food with hungry roost-mates by regurgitating blood. While they can occasionally spread diseases like rabies, they're fascinating examples of nature's creativity in solving the problem of finding food.