In the 25th year of the BBC's Natural History Unit, the second half of a series In 26 parts. Narrator David Attenborough
16: Seeing with Sound
In 1793, Italian naturalist Lazzaro Spallanzani recognised that bats are able to avoid obstacles even when they cannot see. In 1940. it was discovered that bats echo-locate with ultra-sonic sounds.
Brock Fenton of Carleton University, Ottawa, Don Griffin of Rockefeller University, New York, and David Pye of Queen Mary College, London, describe the echo-location capabilities of gleaners, honkers, whisperers, two-tone, FM and doppler bats.
Written and produced by MICHAEL BRIGHT
BBC Bristol