Dolphins, bats and some whales use echolocation in order to gain information about their surroundings through reflection of sounds. Ben Underwood learned the art of echolocation, which helped him lead a normal life even though he spent it without using his sight.
Ben was born in 1992, and was diagnosed with retinal cancer at the age of two. His eyes were removed when he was only 3 years old. When he turned five, he learned how to use echolocation through producing clicking sounds with his tongue. By distinguishing the reflected sounds, he could gain information about his surroundings easily. Ben died in 2009 from the same type of cancer that took his sight. Regardless of his disability, through his amazing skill he managed to enjoy his life with rollerblading, skateboarding, playing football and basketball just like a normal teenager.
Nowadays human echolocation is becoming more and more popular all over the world. Daniel Kish, another victim of retinal cancer, leads courses for blind people in order to teach them echolocation so they can also lead a normal life.