Make (sound) waves.
Many animals—including bats, whales, and dolphins—utilize echolocation to locate and identify objects. "Many animals" also includes humans. By actively creating sounds like stamping their feet, snapping their fingers, or making clicking noises similar to other animals, some people are able to sense objects based on their echoes. This process is utilized by some blind people as a way of navigating their environment, using auditory clues instead of visual ones.
Ben Underwood, who lost his eyesight to retinal cancer at the age of two, famously taught himself to echolocate by the time he turned five. By frequently clicking his tongue, Underwood played basketball, football, rode a bicycle, and enjoyed skateboarding. This ability of acoustic way-finding can be taught and many blind people have trained themselves to orient themselves by interpreting the sound waves reflected off of the objects around them.
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