Which mammal is capable of true powered flight?

Bats are the only mammals that truly fly, generating lift and thrust with a flapping wing rather than merely falling slowly with style. The wing is a hand: the bones are enormously elongated fingers with a thin double layer of skin stretched between them, and because each finger can move independently the bat can change the shape and camber of its wing continuously in flight. That makes bats extraordinarily agile, able to hover, turn tightly and pluck insects out of the air in ways a bird's more rigid feathered wing cannot match. Many species pair this with echolocation, calling and reading the returning echoes to build a picture of obstacles and prey in complete darkness, which is why bats own the night-flying insect niche. They make up a very large share of all mammal species, and although insect-eaters are the familiar kind, others feed on fruit, nectar or fish.

Fruit bats generally navigate by sight and smell rather than echolocation, having large eyes instead.