Researchers discovered a "googly eyes" optical illusion that terrifies raptors (eagles) and corvids (crows) so badly, they remain afraid of the eyes, and they will not return to the area where it is visible. The eyes were successfully used to keep the birds away from lethal collisions at an airport.

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Researchers discovered a "googly eyes" optical illusion that terrifies raptors (eagles) and corvids (crows) so badly, they remain afraid of the eyes, and they will not return to the area where it is visible. The eyes were successfully used to keep the birds away from lethal collisions at an airport.