Which Mammals Fly in the Dark?

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Bats are the only mammals which can truly fly in the dark. They are nocturnal and so are active and fly at night. The wing of a bat is different from the wing of a bird. It is a skin-like membrane, the patagium, stretched between enormously long arm and hand finger bones. Most bats are insectivorous while some are fruits-eating. The vampire bats feed on the blood of large mammals and some others feed on mice, voles, frogs and fish. Bats are able to find their prey and avoid obstacles in the dark by using a sound radar
system called echolocation. They emit very high-pitched pulses of sound called ultrasound which cannot be heard by us. The sound waves bounce back to the bat after hitting an object. The bat hears the patterns of these echoes and analyses it to give a 'sound picture‘ of the object and the surroundings.

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