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[Anomalocaris]

Bats and dolphins are not the only mammals who can use biological sonar to echo locate.    Humans can learn to do it too.    Some Blind people such as Daniel Kish make clicking sounds with their tongue and uses the faint echo to paint their surroundings and do things sighted people can not, such as identify from a distance whether visually identical objects are made of metal or wood.     Some of those, Such as Ben Underwood, can do it with such dexterity, and process so much information from the echos so quickly, they can skateboard, play basketball, and ride bicycles.

Magnetic resonance imaging of the brains of human echo locators shows the primary visual cortex, part of the brain normally to process visual signals, have been repurposed to process auditory signals.    They literally see with sound.