Published: June 2007
Did You Know?
In Did You Know? the National Geographic magazine team shares extra information we gathered to expand your knowledge of our featured subjects.

Bats, the only mammals capable of powered flight, have been clocked at more than 30 miles (50 kilometers) an hour in the lab. They can make 180-degree turns in less than a wingspan and can even fly upside down. How do they do it? Check out their wings.

A bat's wing is naked: just skin well supplied with a network of blood vessels and nerves. But the skin is rubbery and durable, resisting tears and punctures. The few transparent hairs that sprout from its surface are thought to be used to detect airflow across the wing, allowing the bat to respond to changing flight conditions. There are small muscles in the wing that pull and tug the skin during flight to enhance aerodynamics. Scientists are studying the exceptional properties of bat wings to create new designs for all kinds of flying machines.

Because of the structure of their wings, including 24 flexible joints in each one, bats can create wing shapes and motions no bird or insect ever could. In fact, according to a study released earlier this year, bats use a different mode of flight than do birds or insects. During flight the part of the bat wing closest to the animal's body acts like an airfoil: As the air moves over the wing it creates lift. The parts of the wing closer to the wingtip move in a circular up-and-down movement, which gives the bat forward motion.

Bats are such nimble aeronauts that they make catching insects in their mouths in the dark of night look like a game. Certain species take the game a step further, using an agile wing itself to catch the insects. That's not so surprising; the wings are hands after all.

—David A. O'Connor