Vampire Bat
Desmodus rotundus: Bat's All, Folks!

Look, up in the sky! (We mean WAY up, as in 15,000 feet!)

Hungry? You may follow your nose to the nearest pizza place, but vampire bats use their ears to figure out where the next meal is. Like many species of bats, these Central and South American mammals use "echolocation" to find food—and find their way—in total darkness.

To accomplish this neat feat, the bats send out high-frequency sounds that bounce off other objects. By listening to the sounds, or echoes, that bounce back, they can determine exactly where an object or prey animal is. If a vampire bat comes upon a sleeping bird or other prey mammal, he makes a small bite in the skin and laps up the blood from the wound.

One other cool thing about vampire bats is that their knees face backwards. This adaptation allows them to hang upside down...just thought you might knee-d to know!