During World War II, the U.S Military funded a project to train pigeons as pilots for glider bombs.
American Psychologist, Skinner, trained pigeons to aim and peck at target and anytime the pigeon succeeded it would receive some food in return reinforcing the pecking behavior.
The guidance system of the glider bomb consisted of three lenses mounted in the nose of the bomb, which projected an image of the target on a screen. Whenever the bomb would start to go off track, the picture of the target would move from the center to the edge of the screen, but the trained pigeons would continuously peck at the center of the target which would bring the bomb back on track
The project was cancelled in 1953 when the reliability of electronic guidance systems was proven.
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