BATS

In the animal kingdom bats are classed as mammals, a large group that includes men, mice, lions, and dogs. Like all mammals, bats nurse their young on milk. Like most mammals, they have hair and bear living young. But in one ways bats are different from all other mammals: bats can fly.

There are mammlas knows as flaying squirrels and flaying lemurs, but they do not truly fly. Rather the glide from tree to tree. Bats are the only mammals that move through the air with wings.

A bat’s wings is not like a bird’s wings. The bird’s wing is formed chiefly of feathers; these grow out from bones that make the front edge of the wing. The bat;s wing is a double layer of skin stretched over the thin bones of its arm and fingers. A bat’s wing is something like a kite.
A bat’s skeleton is the framework for a living flying machine. The arm extends from a shoulder socket, bends at the elbow, and ends with long, slender fingers. The fingers are almost as long as the rest of the body. They support the main part of the wing and are webbed. These webbed fingers account fior the bat’s scientific name, chiroptera, meaning “wing-handed.”
The wing covers all fingers except a short thumb, which is left free. A sharp claw on the end of the thumb forms a hook at the top of the wing. When its wings are folded, the bat uses its hooks to climb tree trunks, rocky walls, and other rough surfaces.
The skin connecting the webbed fingers is also attached to the bat’s clawed feet. This makes the back part of the wings. Most bats have an extra flap of skin connecting their feet. While flaying, many can fold this flap into a pocket for cathing insects.
Since its legs bones and leg muscles are included in its wings, a bat can fly more easily than it can walk. But the feet are far from useless. Like human hands, a bat’s feet can turn inward, which enables them to grasp objects like twigs, and branches. Sharp claws hook securely into crack or around bumps in the wall or ceiling of a cave. These claws are so strong that they support the bat’s whole weight, even during sleep.
When resting, a bat can use its claws to cling to a wall or tree trunk-or it may hang upside down, suspended by its feet. Bats hang upside down because it is easier for them than perching upright. Their small legs are attached to the body in a way that makes perching in awkward.