Bats are the only mammals that can fly

Have you ever wondered if any other animals can fly, apart from the birds? If you thought of bats, then you would be right. Bats are the only flying mammals in the world. There are over 1,100 species of bats worldwide, and all fly. Flying squirrels and similar mammals can only glide at best but cannot fly. 

How are the bat wings formed? 
Bats have the same number of fingers as us: five. All these “fingers” are connected by a layer of skin (called membrane), so thin that light can pass through it. Another membrane connects its fingers to the main body. This entire structure connected by a thin skin membrane is what we observe as a bat’s wings. The small thumb at the top peeps out of its wings which the bats use to cling to surfaces like a branch of a tree. 

How do bats fly? 
But how do bats fly using these wings? Bats’ wings are like their webbed hands. They can fold their wings, the way we move our fingers. To fly, bats row their wings through the air like we use our hands for swimming. They can also apply brakes.  

What helps them to pull their wings up and down are the strong muscles in their back and chest. Some of these muscles pull the wings up in an “up-stroke” and some of these bring them down during a “down-stroke“. To make an upstroke, bats fold their wings. This reduces the opposition from the air and they save their effort. During the “down-stroke” they push their wide wings downwards with great force and in return, they get a lift from the air and rise upwards. 

Also, to be able to fly, bats try and keep their weight down. They digest their food extremely fast, sometimes excreting within 30 to 60 minutes of eating.  

Do they take off from the ground? 
A large majority of bat species cannot take off from ground level. These species of bats will hang on a cliff or a tree. By doing this, they can take off from that position. When a bat is launching itself, it will drop from the hanging position before flying.   

However, a few bat species, such as horseshoes and vampire bats, can take off from the ground. These species descend to the ground in the search of food.  

Why do they come out at night? 
Venturing out at night helps the bats to avoid some fierce birds that may hunt them down during the daytime. Also, they take advantage of so many insects that are active at night, with no other animal around to catch them. 

When flying at night, bats use echolocation to notice barriers and predators.  Echolocation is a mechanism where bats emit ultrasonic sounds, which moments later send echoes. When the echo returns to the bat, they can easily detect and locate an obstacle. Also, bats are not blind. Infact, they can see almost as well as humans.