Science: The Giraffe Problem

Giraffes fascinate physiologists, as well as children at the zoo. The most interesting point about them, physiologically, is that they manage to keep their heads supplied with the proper amount of blood. When a full-grown giraffe lowers its neck to drink and then raises it upright, its head changes level by 19 ft.—from 7 ft. below its heart to 12 ft. above it. Some fancy hydraulics is obviously called for to keep the blood flowing properly at all times.

In the South African Medical Journal, German-born Physiologist R. H. Goetz reports how he solved a part of this problem. He did it...

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