If bats are blind, why do they have eyes?

Asked by: Leslie Finch, Llandysul

Despite the famous idiom, bats aren’t blind. All bats rely on sight to find food, avoid predators and navigate to and from roosts. As expected in a nocturnal mammal, their eyes are heavily loaded with photoreceptor cells called rods, which maximise their ability to see in the dark.

At night, however, most bats use echolocation to find prey – sending out ultrasonic sound waves and listening for the echoes. So bats can ‘see’ with both their eyes and their ears.

Read more:

• Why do bats live in caves?
• Why don’t prey animals have eyes in the backs of their heads?

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