Bats are the only mammals capable of true sustained flight. Their forelimbs are wings made of two thin layers of skin stretched over arms, 4 fingers and a thumb. A bat”s fingers are very long compared to its body and their wings go all the way down their body and partway down their legs. The muscles in a bat”s fingers are also very strong, making it easy for them to connect their claws to hang onto hard surfaces. Unlike birds that flap their wings up and down, bats “swim” through the air with wing beats as rapid as 20 beats per second.
It is true that bats can climb trees. Their thumbs extend out of the wing as a small claw which they use to latch onto hard surfaces and climb. This also helps them reach a high launching point for flight takeoff. You may spot a bat walking and/or climbing with their wings folded or you may spot them hanging upside down in a tree, sometimes by one hindfoot, or swinging from tree branch to tree branch.
These winged creatures have been around for about 50 million years and have also not changed much over the years. Scientists believe that they may have evolved from mammals that could climb in and live in trees and leap through the air from branch to branch to catch insects. It is also a possibility that over the years a bat”s wings may have evolved from limbs.
Melodye Buskin says
I live in suburban Chicago where there are a lot of trees whilst walking my dog I think I saw one fly through the air then climb up the side of a tree. Alternatively it could have been a flying squirrel because it was dusk and ive read both species are nocturnal. It is weird, though, to see something fly through the air and attach itself to the side of a tree and proceed to then climb up it other than a bird like a nuthatch or woodpecker.