Why Don’t They Die From Heatstroke?

By Awake! correspondent in South Africa

Most mammals maintain a body temperature of about 99 degrees Fahrenheit [37° C.]. If the temperature of your body rises above 106 degrees Fahrenheit [41° C.], vital brain cells may be damaged, at times resulting in death. What protects you from heatstroke? A “thermostat” in your brain detects when your temperature rises above normal, and a message is sent to millions of tiny glands in your skin. You then begin to sweat profusely. As the moisture evaporates, it cools your body. This is a marvelous mechanism, common to many mammals.

Now, look at this shot of the handsome oryx, or gemsbok, taken in the African Namib Desert. Since water is scarce, the oryx cannot afford to waste precious body fluids. What does it do instead of sweating?

“In order to shield its brain from the overheated blood,” explains zoologist Richard Goss in the book Maberly’s Mammals of Southern Africa, “it has a fine network of blood vessels close to the surface of the nose; blood passes through these veins and is cooled by the air flowing in and out of the nose as the gemsbok pants; this cool blood is then used to lower the temperature of the warm blood on its way to the brain in much the same way as water is used to cool a hot mechanical engine.”

Thanks to this cooling system, oryx thrive in the hot, dry deserts of Africa. States The Encyclopedia of Wild Life: “It is thought that the Oryx can exist indefinitely without water, absorbing whatever moisture it needs from desert plants. Certainly it seems quite happy in remarkably high temperatures​—up to 40° C [104° F.].” And what if the oryx’s temperature should reach the critical 106 degrees Fahrenheit [41° C.]? Would this bring on a heatstroke? No. The oryx can “tolerate a body temperature increase of some five or six degrees above the 37° C [99° F.] regarded as normal for most mammals,” explains South African professor of zoology John Skinner.

Indeed, man was not the first to design an efficient radiator!