Geese: High-Altitude Engineering

The atmosphere at 24,000 feet (7300 m) contains only 30–50% of the oxygen at sea level—barely enough for most humans and animals to stay conscious. But scientists have recorded bar-headed geese regularly crossing the Himalayas at that altitude on their annual migration. Some observers have even reported seeing the geese as high as 29,000 feet (8800 m).

How the geese not only survive but also vigorously flap their wings without losing a beat has been a mystery for decades.

To solve this mystery, researchers decided to place trained geese in a wind tunnel and cover their faces with oxygen masks. (How they managed to fit geese with oxygen masks is a mystery for another day.) The study showed that bar-headed geese can slow their metabolism and cool their blood for high-altitude flight. Colder blood stores more oxygen. Unlike low-flying birds, bar-headed geese also have extra capillaries surrounding their chest muscles. More oxygen in the blood and more blood to the flight muscles mean higher flying without overexertion.

In love for his creation, God gave these birds the ability to adapt to extreme situations. His eye is on the sparrow—and the bar-headed goose.

This article was taken from Answers 15, no. 1 (January–February 2020): 19.