Prehistoric bats such as Icaronycteris were not very different from the ones found today. They even hunted in the same manner—flying around in the night skies and swooping over places where plenty of insects gathered, such as among the trees or above lakes. Some scientists suggest that these early bats flew at night to escape the clutches of predatory birds that hunted during the day.
■ When: 55–50 million years ago (Paleogene)
■ Fossil location: USA
■ Habitat: Woodlands of N. America
■ Length: 1 ft (0.3 m)
■ Diet: Insects
We know Icaronycteris was a night-flying bat that caught prey in midair because moth scales have been found in the stomach of one fossil. To catch moths at night, modern bats send out pulses of sound and use the echoes to “see” in the dark (echolocation). The structure of Icaronycteris’s inner ear suggests it was able to use echolocation, too.
Icaronycteris is one of the earliest known bats. Unlike some modern bats, its long tail was not connected to its hindlimbs by a flap of skin. However, it did sleep hanging upside down from a tree branch or a cave roof.
DID YOU KNOW…?
Icaronycteris is named after Icarus, the son of the ancient Greek craftsman Daedalus. According to Greek myth, Icarus and his father escaped from prison on wings attached by wax. Icarus flew too close to the Sun. The wax melted, and he plunged to his death in the sea below.
Bats are the only true flying mammals. They have membranes of skin between their arms and fingers, which have evolved into long wings. Some bats, such as this fruit bat, or flying fox, feed on fruit instead of insects.