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Unlike some human-made sonars that rely on many extremely narrow beams and many receivers to localize a target (multibeam sonar), animal echolocation has only one transmitter and two receivers (the ears) positioned slightly apart. The echoes returning to the ears arrive at different times and at different intensities, depending on the position ...
The term "echolocation" was coined by zoologist Donald Griffin in 1944. But the phenomena was known about earlier, for example, Denis Diderot reported in 1749 that blind people could locate silent objects. [1] Human echolocation has been known and formally studied since at least the 1950s. [2]
Animal echolocation, animals emitting sound and listening to the echo in order to locate objects or navigate; Echo sounding, listening to the echo of sound pulses to measure the distance to the bottom of the sea, a special case of sonar; Gunfire locator; Human echolocation, the use of echolocation by blind people; Human bycatch
Other animals, such as birds and reptiles, also use them but they may use them differently, and some also have localization cues which are absent in the human auditory system, such as the effects of ear movements. Animals with the ability to localize sound have a clear evolutionary advantage.
Animal echolocation, non-human animals emitting sound waves and listening to the echo in order to locate objects or navigate. Human echolocation, the use of sound by people to navigate. Sonar (sound navigation and ranging), the use of sound on water or underwater, to navigate or to locate other watercraft, usually by submarines.
Examples include echolocation of bats and dolphins and insect antennae. Using self-generated energy allows more control over signal intensity, direction, timing and spectral characteristics. By contrast, passive sensory systems involve activation by ambient energy (that is, energy that is preexisting in the environment, rather than generated by ...
Jamming occurs when non-target sounds interfere with target echoes. Jamming can be purposeful or inadvertent, and can be caused by the echolocation system itself, other echolocating animals, prey, or humans. Echolocating animals have evolved to minimize jamming, however; echolocation avoidance behaviors are not always successful.
The examples include ground vibrations produced by elephants whose principal frequency component is around 15 Hz, and low- to medium-frequency substrate-borne vibrations used by most insect orders. [14] Many animal sounds, however, do fall within the frequency range detectable by a human ear, between 20 and 20,000 Hz. [15]