Greater horseshoe bat flying at night towards camera

Echolocation and ultrasound

Ultrasound is high frequency sound that's above the range of human hearing. Some animals produce ultrasound for communication or for navigation. Baby rats call to their mothers with high pitched squeaks inaudible to humans. Dolphins use ultrasound to echolocate and find their way around in murky or dark water.

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Video collections

Take a trip through the natural world with our themed collections of video clips from the natural history archive.

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