How a camel beats the heat of the desert?

A picture of a camel enduring the heat of the desert.

Coping with the heat of the desert

Physiology professor Knut Schmidt-Nielsen conducted a study of camels in the Sahara Desert.

His findings reveal how the camel is able to endure the extreme heat of his environment:

In the burning heat of the desert an inanimate object such as a rock may reach a temperature of more than 150 degrees Fahrenheit.

A camel in such an environment, like a human, maintains a tolerable body temperature by sweating.

But where the temperature of the man remains virtually constant as the day grows hotter, the temperature of the camel increases slowly to about 105 degrees Fahrenheit.

As the temperature of the camel rises, the animal sweats very little; only when its temperature reaches 105 degrees Fahrenheit does it sweat freely.

The camel’s elevated temperature also lessens its absorption of heat, which of course depends on the difference between the temperature of its body and that of the environment.

The camel lowers the heat load on its body still further by letting its temperature fall below normal during the cool desert night.

At dawn its temperature may have dropped as low as 93 degrees Fahrenheit.
Thus much of the day will elapse before the animal’s body heats up to 105 degrees Fahrenheit and sweating must set in.

As a result of its flexible body temperature the camel sweats little except during the hottest hours of the day, where a man in the same environment perspires almost from sunrise to sunset.

The camel employs camel-hair insulation to lower its heat load still further.

Even during the summer, when the camel sheds much of its wool, it retains a layer several inches thick on its back where the sun beats down.

The shorn animal produced 60 per cent more sweat than an unshorn one.

The camel’s hump also helps indirectly to lessen the heat load on the animal.

Nearly all mammals possess a food reserve in the form of fat, but in most of them the fat is distributed fairly uniformly over the body just beneath the skin.

In having its fat concentrated in one place the camel lacks insulation between its body and its skin, where evaporative cooling takes place.

The absence of insulation facilitates the flow of heat outward, just as the insulating wool slows the flow of heat inward.