The camel's amazing nose

Twentieth-century science has exploded two myths about the camel, the one physiological and the other archeological. The physiological myth, held for ages, has been that the camel's secret of desert survival lies in its ability to store large quantities of water in its hump, its stomach, or in some unknown reservoir. Pliny the Elder, the Roman naturalist who died investigating the eruption of Mount Vesuvius in A.D. 79, appears to have been the earliest writer to compare the camel's stomach to a water tank. But the secret of the camel's survival is not its hump or its stomach, but simply conservation of water.

The camel of the Bible is most likely the one-humped dromedary, Camelus dromedarius, rather than the two-humped Bactrian camel, which originated in an area northeast of Iran (ancient Bactria). The Creator has designed the dromedary in such a way that every cell of the body is programmed to conserve water. Although not known for its graceful appearance, the bulky camel's body has extra layers of fat that help keep out the desert heat. (Usually we think of fat as helping to keep heat in.) Thus when the camel is short on water, it can tolerate a substantial rise in body temperature, reducing greatly the need for perspiration and in turn lowering water loss, A camel's temperature may vary from 95° F. in early morning to 106° in the heat of midday. Its kidneys are geared to retaining water, and its body tissues are adapted to the extremes of dehydration and the shock of sudden water intake after going days without drinking. At a single sitting, a camel can drink an amount equal to 25 percent of its body weight, or the equivalent in volume to the gasoline tank of a large-sized car! However, this water cannot be stored in the stomach; it must either be rapidly absorbed by body tissues or be excreted.

Recently," scientists have discovered that the real secret of the camel's remark able ability for desert survival is found in its ingeniously designed nose. The camel's nose acts both as a humidifier and a dehumidifier in order to minimize body water loss through breathing. Ordinarily, when an animal breathes it exhales air that is loaded with water vapor absorbed from the moist linings of the lungs. This loss is accentuated in desert regions because the extremely dry desert air that is inhaled is exchanged for the moisture-laden air that is exhaled, resulting in a significant net water loss. However, the camel capitalizes on the principle of physics in order to minimize this type of loss—the cooler the air, the less moisture it can retain.

A few years ago Physiologist Knut Schmidt-Nielsen, from Duke University, discovered that the camel has the unique ability of exhaling air that is significantly cooler than its body temperature. By this means it gains a 45 percent overall reduction in the water loss that normally takes place through respiration. But how has the camel mastered the ability to exhale cooled air, when animals normally exhale air that is at body temperature? This secret was not unlocked until 1979, when Schmidt-Nielsen linked up with Zoologist Amiram Shkolnik, of Tel Aviv University. They secured two female dromedaries from children's zoos for their research. Because camels become more irritable and stubborn the hotter the weather, they wanted to make sure that the tamest possible animals would be used. One can imagine the difficulty of attaching a temperature probe or a mask for studying respiration to a camel in 100° weather!

For sixteen days these two camels were confined to a corral without shade or shelter in July near the Dead Sea, where daytime temperatures often exceed 104° F. They were fed only green dates and dried hay and allowed no water. The scientists observed that as the camels began to dehydrate and lose body weight, the air they exhaled became drier and cooler. The air exhaled at night was only 70 to 75 percent saturated, and was a full 18° F below body temperature.

It was not until the two scientists cut transverse slices through a camel's nose (presumably not the camels loaned by the children's zoos) that they discovered the secret of its air-cooling ability, something never reported for any other animal. The camel makes use of another principle of physics: the greater the surface area the faster the rate of evaporation or condensation. And evaporation results in cooling. They uncovered an intricate labyrinth of air passageways in the camel's nose which increases its surface area manyfold over that of a straight passageway. For example, a human nose has only two square inches of interior surface area, while the camel has an incredible 155 square inches of mucous membrane on the nasal interior.

The camel's nose acts as both a humidifier and a dehumidifier with every breathing cycle. The hot, dry air that is inhaled passes over the 155 square inches of moist membrane. This air is immediately humidified by picking up moisture from the nose and cooled in the process, much in the same way that air is cooled when a fan blows it through a moist cloth. This cooler air passes to the lungs and remains at approximately body temperature. When it is exhaled, it is cooled even further by passing over the same nasal membranes, this time by a process of dehumidifying instead of humidifying. The nasal membranes are coated with a special water-absorbing substance that extracts the moisture from the air in much the same way that the cool coils of a dehumidifier in one's home are able to condense moisture from the air. A net savings of 68 percent in the water usually lost through respiration occurs just between the cooling and drying phases of the breathing cycle!

A camel's nose is not much to behold, but the very survival of the animal depends upon it. Although Paul's words are in reference to the human body, they are applicable here: "Those members of the body, which seem to be more feeble, are necessary: and those members of the body, which we think to be less honourble, upon these we bestow more abundant honour" (1 Cor. 12:22, 23). Man is tempted to scoff at appearances, but the camel's nose tells us most eloquently that the Creator indeed knew what He was doing when He designed it.

Another camel myth, this one archeological, has been cleared up by twentieth-century discoveries. It was long claimed that the domestication of the camel did not take place until the twelfth century B.C. at the earliest, and since the narratives of Abraham, Isaac, and Jacob all speak of camels, these narratives could not have been put into writing until the twelfth century. The book of Genesis mentions the camel twenty-four times—nearly as often as the rest of the Old Testament combined. Such references to camels were said to be anachronistic. Early Egyptian artwork from reliefs and murals is noted for its absence of pictures of camels, and in Mesopotamia camels are not commonly pictured as domesticated until the ninth century and later.

Camels are often pictured in battle scenes as well as in trade. The Arabs are pictured seated on camels while being pursued by the Ashurbanipal's Assyrian forces, somewhat reminiscent of the camel-riding Midianites attacking Israel during the period of the judges, their camels being described as "without number" (Judges 6:5). The Black Obelisk of Shalmaneser III, king of Assyria, pictures the Israelite king Jehu bringing tribute in company with tribute-bearing, two-humped camels from other nations.

Now archeology has uncovered evidence indicating that the camel was domesticated as early as the end of the third millennium B.C.—the time of Abra ham—although its use as a burden bearer did not become common until a thousand years later. Camel bones have been found in the ruins of a house located in the midst of the caravan trading town of Mari, dating to about 2400 B.C. The camel is mentioned by the name GAMMAL in cuneiform inscriptions from Alalakh of northern Syria along with a list of fodder needed by domesticated animals. (The closely related Hebrew word for camel is gdmal.) This eighteenth-century B.C^ inscription is matched by a picture of a kneeling camel, which suggests its use in caravans, in an inscription from Byblos, of Phoenicia, also dated to the eighteenth century B.C. It is interesting that this early evidence for the domestication of the camel comes from the upper Mesopotamian cities of Mari and Alalakh, the same general region where the patriarchs Abraham, Isaac, and Jacob had their roots. Corroborative evidence for this has recently been uncovered among the Ebla tablets.

No longer do scholars need to say that the patriarchal narratives are anachronistic and out of date by centuries. The camel has vindicated the accuracy of God's Word. By two strange turns of events the camel has supplied evidence for the divine touch of the Creator, first in His work of creation and design and second in His touch upon the pages of Genesis, producing an account that is both accurate and trustworthy.