2. It’s a bird, it’s a plane…

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Yes, it actually is a bird, but it is one that flies where only airplanes are usually found. The world’s highest-flying bird, the bar-headed goose can fly at altitudes of up to 21,000 feet. That’s about 10,000 feet below the normal cruising altitude of a jetliner. Scientists studying the birds with the aid of GPS transmitters found that their migratory route takes them over the Himalayan mountains where they reached an altitude of 21,120 feet.