Landing Upside Down (IMAGE) Brown University Caption In order to roost upside down on cave ceilings or tree limbs, bats need to perform an aerobatic feat unlike anything else in the animal world. Researchers from Brown University have shown that it's the extra mass in bats' beefy wings that makes the maneuver possible. By flapping both wings with one folded slightly toward their bodies, bats shift their center of mass to perform a flip. Credit Breuer Lab/Brown University Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.