FLYING HIGH
In late 1973, a Rüppell’s Griffon collided with an aircraft over Abidjan on the Ivory Coast. Bird strikes are not uncommon, but what made the abrupt demise of this particular vulture unusual was the altitude at which it happened: 11 kilometres above the ground. That any animal can survive and function at such an altitude is remarkable, even if in this instance the griffon probably reached this height by soaring on thermals rather than in flapping flight.
Birds are inherently better suited to operating at altitude than mammals are. One key factor is the structure of the avian respiratory system. Mammals have a respiratory cycle that involves the inhalation of oxygenated air into the lungs, followed by the exhalation of partially deoxygenated air before the next inhalation. Birds possess a network of air sacs surrounding the lungs, arranged in such a way that oxygenated air flows continuously through the lungs regardless of whether the bird is inhaling or exhaling, providing a far more efficient mechanism for getting oxygen from the atmosphere into the bloodstream.
Diese Geschichte stammt aus der November 2019-Ausgabe von African Birdlife.
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Diese Geschichte stammt aus der November 2019-Ausgabe von African Birdlife.
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MIDRAND marvel
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