Which Mammal Can Truly Fly?

Bats (order Chiroptera) are the only mammals that can achieve true powered flight, as opposed to the gliding of flying squirrels or colugos. Their wings are formed by thin membranes of skin stretched between elongated finger bones, the body, and the hind legs. Bats have evolved sophisticated echolocation (using ultrasonic calls to navigate and hunt in darkness) and are found on every continent except Antarctica. With over 1,400 known species, bats make up about 20% of all mammal species. They play critical ecological roles: insectivorous bats consume vast quantities of agricultural pests, and fruit bats pollinate flowers and disperse seeds for many tropical plants.