Human beings are able to adapt to many unfriendly environments. It is no surprise then, that they have learned to live in the desert and make it their home. Desert dwellers make up less than 1 percent of the world's population, but they include a large variety of native peoples of all races.
Humans are able to maintain a safe body temperature in the desert by sweating. Under extreme heat, a human being may lose as much as 5 pints (3 liters) of moisture in an hour and up to 21 pints (12 liters) in a day. This water must be replaced, however, or the person will die from dehydration. (Dehydration occurs when tissues dry out, depleting the body of fluids which help keep it cool.) Unlike the kidneys of many desert animals, human kidneys cannot concentrate urine to conserve water. The loss of salt through sweating is also a problem, for humans need a certain amount of salt to maintain energy production. If too much salt is lost, painful muscle cramps can occur.
Because the human animal can change very little physically to adapt to desert conditions, humans must change their behavior. This has been done in many ways, from the choice of lifestyle to the development of technologies such as irrigation (watering of crops). The lifestyles discussed in this chapter are the more traditional ones; most desert peoples today have altered these lifestyles in keeping with the modern world.
Until the mid-1900s, many native desert dwellers were nomads—either hunter-gatherers, like the Bushmen of the Kalahari and Namib, or herders, like the Bedouin of the Middle East. They moved regularly, usually along an established route, in order to seek food and shelter for themselves or their herds of animals. Most nomads return year after year to the same areas within a given territory. They know what to expect—when the rains usually come, where to find food or pastures, and where a water supply is located. By the late twentieth century, however, less than 3 percent of desert peoples lived nomadic lives, having been driven from their lands by ranchers or mining companies looking for mineral, gas, and oil resources. Since 1950, many nomadic peoples have moved to cities where, too often, they live in poverty.
The diet of hunter-gatherers consists primarily of plant foods and game animals, although meat is usually scarce. Some, like the Aborigines of Australia, eat the grubs (larvae) of certain insects, which provide a source of protein.
Herding tribes depend primarily upon their animals for food, although they may raise grains or trade for them. In the Sahara, dates from the date palm are an important food.
Many Native Americans found important uses for desert plants. The leatherplant, also called sangre de drago (blood of the dragon), contains a red juice used as a medicine for eye and gum diseases. Wine and jelly were made from the fruit of the saguaro cactus, the fruit of the prickly pear was made into jam, and ocotillo branches were useful as building materials.
The homes of hunter-gatherers tend to be camps, not houses. The Bushmen of the Kalahari, for example, make huts from tree branches and dry grass.
Traditionally, the nomadic tribes of the Sahara, whose shelters had to be portable, used tents made from the hides or hair of herd animals such as goats. The tents of the Bedouin are an example. Village houses in the desert are often made of mud bricks dried in the Sun. Because there is so little rain, the bricks do not need to be waterproof.
In the desert country of Mongolia desert dwellers commonly live in yurts—tentlike structures made from felt created from sheep's wool. The felt is stretched over a wood frame, and a hole at the top of the yurt allows smoke from cooking fires to escape.
Traditionally, some Native Americans of the southwestern desert—the Hopi and Zuni tribes—built homes, called pueblos, from mud, wood, and stone. The thick walls and small windows kept the interior cool. One group, called the Anasazi, who lived around
One advantage humans have over other animals is clothing, which is a substitute for fur. Unlike fur, clothing can be put on or taken off at will. Most traditional desert peoples wear layers of loose-fitting garments that actually protect the body from the heat. A naked person absorbs twice as much heat as a person in lightweight clothes. Also, loose clothing absorbs sweat and, as the air moves through, it produces a cooling effect. As a result, the person sweats less, which conserves water. Today, however, many desert tribes, especially in the Middle East, have at least partially adopted western clothing styles.
The only desert peoples to go naked were the Bushmen of the Kalahari and the Aborigines of Australia. Occasionally, when nights were chilly, they wore "blankets" made from bark, but more often their warmth came from a campfire. Those Bushmen and Aborigines who still live a traditional lifestyle continue to go without clothes.
Some kind of headgear is usually worn by desert dwellers to shield the face from the Sun and blowing sand. The Fulani, who live on the edge of the Sahara in West Africa, wear decorated hats made from plant fibers and leather.
For traditional hunter-gatherers, possessions are almost meaningless. If they favor a particular stone for sitting on, they might carry it along. However, a stone, as well as many other things, gets very heavy after a few miles. Their economy tends to be simple and little trading is done.
A century ago, desert herders were self-sufficient. Their wealth moved with them in the form of herd animals, jewelry, tents, and other possessions. Commerce usually involved selling goats, camels, or cattle. In the Middle East, the discovery of oil made important changes in the economy. In some cases, sweeping modernization made irrigation and food production more stable. Nomads settled in one spot and became farmers. In other cases, the wealth fell into the hands of a few, while the large majority lived in poverty.
The fact that the desert is so unfriendly to human life has helped preserve it from being overrun by those who could destroy its ecological balance.
As long as traditional lifestyles remained in effect, the human impact on the desert was not severe. Desert dwellers understood the need to maintain balance between themselves and their environment. While animals and plants were used for food, they were not exploited (overused), and their numbers could recover. Since the introduction of firearms and the rapid growth of human populations, however, many plants and animals have become threatened.
Desertification, which mean the loss of plant life, continues in spite of efforts by conservationists (people who wish to preserve the environment) to stop it. Several popular desert plants such as cacti, and animals such as lizards, are sold at high prices to collectors. Many of these species are threatened as a result.
Overpopulation has diminished many natural resources. The digging of wells has caused the water table (the level of ground water) to drop in many desert regions. Supplies of oil and minerals are being removed from beneath the desert surface and cannot be replaced.
For thousands of years, crops have been grown in desert soil with the aid of irrigation (mechanical watering systems). Furrows were dug between rows of plants, and water pumped from wells and allowed to run along the furrows. In modern times, dams and machinery are used to control the rivers or pump groundwater for irrigation, allowing many former nomads to become settled farmers. To irrigate large cotton farms in the Kara Kum Desert of central Asia, for example, water is brought from the Amu Darya River by means of a canal 500 miles (800 kilometers) long.
However, irrigation must be controlled. If too much groundwater is pumped, it may be used up faster than it can be replaced. When the water table drops in regions near the ocean, the land may slump. Salt water may enter aquifers (underground layers of earth that collects water), destroying the fresh water. Another problem irrigation can cause is an accumulation of salt in the soil. All soils contain some salts and, if irrigation water is used without proper drainage, the salt builds up within the surface layers and plants will no longer grow there.
People have impacted the desert environment in several ways. Drilling for oil and mining for other resources requires roads. The people who operate the drills need houses. Most of these changes have occurred along the Mediterranean in mineral-rich countries. However, the deep centers of deserts have usually not been disturbed. There, roads remain tracks and have escaped being blacktopped.
The world's climate may be changing because of human activity. If so, the climate of the desert will change as well, and no one knows for sure what that will mean.
The Bushmen and the Tuareg are two groups of desert peoples commonly found living in the desert.
The Bushmen of the Kalahari and Namib Deserts of Africa live in clans consisting of several families. A clan's territory is about 400 square miles (1,036 square kilometers). Clans move according to the rains or the seasons, returning to familiar campgrounds year after year, and their territory includes good waterholes. Bushmen live off the land, eating berries, roots, and wild game. Plants, which make up the greatest share of their diet, are gathered by the women. Bushmen are expert trackers and use these skills to hunt game for food with bows and poisoned arrows. The meat is cut into strips and dried so that it will keep. Bushmen are not tall, ranging between 55 and 63 inches (140 and 160 centimeters) in height. This may be partially due to a diet deficient in some nutrients.
Overnight shelters built from grass and branches provide protection from the wind. In the winter, clans may break up into smaller groups and build stronger huts that will keep out the rains. Today, the Bushmen number approximately 20,000. Probably fewer than half of those still live as hunter-gatherers.
The northern Tuareg of the Sahara depend upon the camel for their livelihood, grazing their animals on what little pasture exists on the desert fringes. Camels may be killed for meat or their milk used to make butter and cheese. They are also the primary means of transportation. Since the Tuareg are traders, camels are essential to carry goods such as cloth and dates.
The southern Tuareg tribes are more settled. In recent years, as a result of technology that allows the digging of deep wells, the Tuareg have established cattle ranches on the edges of the Sahara. However, the land is often overgrazed and more territory is lost to the desert every year.
Tuareg men wear a characteristic blue veil wound into a turban (head covering) on their heads. Both men and women wear loose robes for protection against the Sun. An indigo (blue) dye is used to color some clothing. Because it often rubs off on the skin, the Tuareg have been known as the "blue men."
Homes are usually low tents made of animal hides dyed red. The tent roof is supported by poles and the sides are tied to the ground with ropes to keep out the wind and sand. During the hottest parts of the year, the Tuareg build a zeriba, a large, tall hut made from grasses attached to a wooden frame.
The Tuareg have always been known for their ability to fight. Before firearms were introduced during the eighteenth century, they made impressive weapons such as daggers and swords. They now, however, prefer high-powered rifles. Historically, the Tuareg have had a tendency to raid other tribes, and wars between one tribe and another may last for years.
It is estimated that the Tuareg number as many as 500,000 people. This figure is only approximate, however, since the Tuareg are nomads and are rarely in one place long enough for a reliable count to be made.
Source: "Desert." U·X·L Encyclopedia of Biomes, Vol. 1. U·X·L, Detroit: 2000.