Rüppell s vulture flies at altitudes above 11,000 metres, higher than Mount Everest.
Why it is true
This species of African vulture can fly at extreme altitudes because it has a special haemoglobin that captures oxygen very efficiently, even in thin atmospheres. It has been recorded at over 11,000 metres, where the air is almost unbreathable for most birds.
Source: National Geographic
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