Page 55 - The Miracle of Migration in Animals
P. 55
HARUN YAHYA
At altitudes such as 6,000 meters (19,690 feet)
where the oxygen content is half that of ground
level, birds can still fly with ease, where a person
who is standing still may have difficulty breathing.
At altitudes above 7,000 meters (23,000 feet), a
person without physical training may lapse into
unconsciousness and die. However, a flock of
migrating whooper swans has been observed
flying at 8,230 meters (26.904 feet) above sea level.
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