The inhabitants of the Sahara fall into two groups: nomadic and settled folks. The line of demarcation between the wandering and the sedentary elements in the population is not sharply drawn. During the seventh century AD, before the Arab invasion of North Africa, the Sahara was inhabited by two distinct types of people, dark-skinned or Negroid, and light-skinned.
Archeological evidences suggest that “Neolithic” Negroid groups from Sudan began to spread northwards some five thousand years ago through the entire length of the then relatively fertile Sahara. Classical authors from the time of Herodotus on refer to “Ethiopians”-a Greek word which literally means people “with burnt faces”-as occupying all the land to the south of Libya.
Most of the agricultural centers of the western half of the Moroccan Sahara were inhabited by dark-skinned and white folk. The dark-skinned were referred to as the “Haratin”. In oasis society the Haratin occupied a modest position, working as “sharecroppers” in the plantations of landlords who were nearly always white and often warlike nomads. The Haratin were regarded as being in a different class from the slaves “abids”. It has often been thought that the Haratin must be the descendants of Negro slaves, brought to the oasis by their Berber masters. But the Haratin are not only of slave origin; although they possess some Negro features, the shape of their nose and face is often quite unlike that of Negroes of the western Congo rain forest, but rather similar to that of the people of Somalia.
White people of Berber and Arab stock constitute the other group of the population of the Sahara. But a distinction should be drawn among the light-skinned inhabitants of the Sahara between Arabic-speakers and Berber-speakers. The tribes of nomads in the northwest of the Sahara are people of Arab descent who entered North Africa from the east and fixed there during the Almowahid’s period “12th century”. But other Arabic-speakers represent tribes of Berber origin that have come under strong Arab influence.
There are a number of different Berber-speaker clans among the population of the Sahara, which are the inhabitants of the North, Nul-Lemta, Tamdelt, Sijilmassa, Goulmim, and Tindouf. Arabic-speakers are inhabitants of the northwest of the Sahara.
Classical writers are less informative on the people of the Western Sahara, before the arrival of the Arab tribes. One must refer to the works of medieval Arab geographers and historians, and according to Ibn Khaldoun, the Zenata was one of the most important Berber branche that established in Morocco. The Zenata people were nomads who had migrated from the Midle East in historic times and occupied the northern belt of the Sahara. The other Berber branch was the Sanhaja. The nomadic Sanhaja established in the Western Sahara. Sanhaja comprised a number of tribes, such as the Jazoula,Lamtuna,Lamta and Znaga.
The other people who had been wandering along the Sahara were the Touareg who appear to have been associated with the Sanhaja. But, beginning with the eleventh century, Arab tribes of nomadic standards, the Banu Hilal, started to move across the northern Sahara and later spread into the western desert, causing the Zenata Berbers either to migrate northwards or melt with the Arab Hilalians. Many of the Sanhaja tribes were reduced to vassal status, for a while, by the Banu Hilal. The Touareg, on the other hand, protected by their mountains in Air and Ahaggar, and living away from the main trade-routes were able to preserve both their language, the tamahiq, and their tradition and culture.
Today the Touareg are found in a number of tribal confederations, whose area extends from Mauritania in the northwest, to Mali, the Niger and beyond. The Touareg’s confederations are divided politically into tribes which are subdivided into clans and the latter into fractions. Socially the nomadic population is divided into three main classes, the “noble”, the “vassals” and the Negro slaves. Their language, the tamahiq, is a Berber dialect, and their alphabet, the tifinaq, is partly derived from the ancient Libyan script. The most striking characteristic of the Touareg is the curious custom of men covering their faces with a lit ham or veil, leaving only the eyes exposed. The Touareg are Muslims, but they retain many practices belonging to earlier religions.
Other characteristic of the Touareg is the high status acquired by women in their society. The Touareg’s social organization lies on clans of matriarchal lineage. Inheritance and succession follows the mother side, except the residence which is patriarchal. The woman is relived of all household duties, by the enjoining of servants. Her leisure time is spent in handicraft, poetry and music. Touareg women, contrary to men, are skilled in reading and writing, and own most of the family’s cattle of goat and camels.
The nomadic folk of the Sahara represent the best adaptation of human life to desert conditions, and wherever verdant land is found; there they go seeking for water and pasture. Nomadism is as much a scientific mode of living in the boundaries of the Sahara as industry in Casablanca or Tangier. Action and reaction between the townsfolk and nomads of certain zones were and are still being motivated by the urgent dictates of self-interest and self-preservation. The nomad insists on extracting from his more favorably situated neighbor such resources as he himself lacks, by peaceful methods, sometimes force was used in the past. In Morocco, the nomad, as a human being,is today as he was in the past,and as he might be in the future. His culture pattern has always been the same. Almost immune to the invasion of exotic ideas and to progress, the nomad still lives, as his forebears did, in black tents of goats’ or camels’ hair, and grazes his sheep and goats in the same fashion and, probably, in the same zones.
Vegetation of the desert
With the exception of the plants growing near waterholes, the vegetation of the desert resorted to important biological changes to adapt to the aridity of the desert, and to withstand the high evaporation, main cause of dryness, and to high temperatures and storming winds. Moreover, some of the plants play an important role in the desert, dispersing the particles they carry, causing changes in the soil.
Biological and Morphologic types
Some plants grow in the desert just after a rain shower, to go, afterwards, through a quick short living cycle, which may last but a few days. These are plants whose need in water is almost similar to those growing in humid zones. Other plants, on the other hand, are hardy and show morphologic, anatomic and physiologic characteristics, proving their remarkable adaptation to the dryness of the atmosphere and to the salinity of the soil. These plants root deeply or spread their roots over the surface of the soil, such as the green latex tree, the rolling brush and the different acacias trees.
For some vegetation water problems are reduced either by morphologic evaporating surfaces which are tiny, or by their capacity of storing water. Other natural curiosity among vegetation of the desert is the distance kept between them, which shows a natural adaptation to avoid rivalry between their roots to access the underground water reserves. Many plants adapted to the sand of the desert by developing a system of horizontal rooting which allows their capturing of rain water and moisture. The roots of some plants sink to about 30 meters deep to reach water. The most common of these plants is the acacia tree. Shaped like an umbrella, the acacia reaches heights of up to 3 meters and draws water from a depth of down to 35 meters. This tree spreads between Tafilalet and Sudan. The other tree is the tamarisk whose bark is used for the tanning of leather.
There is another curious plant growing in the arid steps of the Moroccan Sahara, the “tawarza”. This plant of a succulent aspect adapts to the dryness of the desert by storing enough water in its fleshy trunks. The “tawarsa”, is a latex small tree, of hard trunks and large ever-green leafs. The tree bears a toxic avocado-like fruits and grows in the arid steppes of the Anti Atlas.
The fauna of the arid zones of the desert is poor, in general, and is represented by most of the ground and sweet-water zoological groups. But only of those belonging to the species which have adapted biologically to the barren dry zones of the desert. Their anatomic adaptation is important: relative dimensions, pigmentation (black, or black and white insects, clear colored mammals and birds) scaled fingers of lizards, hairiness, developed in the soles of the legs of some mammals (hares, fennec, cat of Marguerite).
The physiological and eco-ethological adaptation, had, on the other hand, largely marked the life of the fauna in the desert: resistance to dehydration and to heat, adaptation to the scarcity in food. The species represented in the arid zones belong, according to the zoological groups, either to tropical kind or to species belonging to temperate zones, such as the rodents of the Sahara. Three types of this “rat of the sand” live in the Sahara, and the three are nocturnal and feed on grains. These rats dig their burrows far from any bushy spots. Their burrows enjoy of a microclimate, when the hygrometry (degree of humidity) is high, and the average temperature oscillates between 20 and 25 degrees C.
These rodents are endowed with extraordinary natural means. A remarkable visual memory allows them explore vast distances of several kilometers and return back to their burrows. The hypertrophy of their ears enables them catch remote signal sounds.
Water problem in the Desert
The dryness of the arid zones is due, not only to lack in rain, but also to the high evaporation which causes a dramatic decrease in artesian waters. As everybody knows, water is an essential to the continuity of life, and if some animals could do without food for many days, lack in water, under any form, would cause a progressive loss in their weight and then death. A loss of 10 per cent of water in any living organism would provoke serious troubles; a loss of 12 percent would be fatal to men. Certain animals could resist longer to dehydration such as the camel whose weight could be reduced by 30 percent during draughty periods without any harm. Several mechanisms of dehydration are generally distinguished, and the most typical case happens when an active living creature loses water and salt, simultaneously, after a significant sweating. The remedy is to provide a reasonable quantity of these two elements, with moderation, to prevent a secondary osmotic imbalance, which could be more serious.
To the evaporation of water by sweating, should be added the low quantity evaporated through breathing, and the amounts evacuated by the body through its natural outlets. The loss in water is recovered either by drinking liquids or from food containing liquids. The animals of the desert are classified according to their degree of dependence in water. Some need water every now and then. Others could do without for several days. A third kind could do, absolutely, without water, and would live only on low hydrated food, such as grains, from which their metabolism knows how to extract enough metabolic water.
Animals depending strictly on large amounts of water
These are the big mammals of the land, whose life revolves around water sources, further of which they could not move. These animals could not do without water, and the surface of their territory shrinks in proportion to the increase in desertification. These are the big antelopes, the giraffes, the rhinoceroses, the elephants and the lions, which, once, have populated the actual expanses of the Sahara, and had to retire to the zones of the “sahel”.
The birds are the other animals that could not live without water, though their low need in this element, except for short periods of time. But their ability of flight and their high speed allows them reach remote sources of water. That is the case of the pin tailed grouse which ponds its eggs, sometimes, at a distance of 50 kilometers of any waterhole. The male grouse takes care of quenching the thirst of the spring little chicken grouses, by carrying water in its feathers. But nothing is known about the needs in water of the desert’s birds of prey, whose territory is immense.
The dew abounds frequently in certain arid region of the Sahara. Formed by the extreme cold of the night which condenses the liquid drops over the hairy plants of the steppe, the dew makes up a substantial, early morning, supplement in water for the Oryx (gazelle), as for the small birds.
The Camel (dromedary)
The dromedary is, by far, the typical animal of this category. Legend bestows him with exaggerated capacities, but the animal is endowed with unusual attributes which makes of him the most valuable domestic animal of the Sahara. There are two species of camels: the camel of Bactrian of the cold Asiatic deserts, characterized by its two humps, and the domestic dromedary, of the Sahara of North Africa and of Arabia. The camel can go for about twenty-five days in winter and about five days in summer without water. According to the experiments of K. Schmidt and Nielsen, a camel weighting 450 kilos lost 100 kilos after eight days without water in winter time. People believe that the dromedary keeps an important water reserve in his stomach, which is not true. In fact, the animal, when thirsty, would absorb about hundred litters of water in five minutes, of which only seven litters of a nauseous liquid are kept in his stomach. The hump contains no water but an important quantity of fat which makes up a reserve of energy for the animal. When this fat is used, as required, by the metabolism, a certain quantity of water is formed by oxidation and made to circulate immediately in the body.
The later camel (dromedary) is believed to have been introduced into Egypt by the Persians during the sixth century B.C. Alexander the Great used camel transport on his expedition to the Oracle of Jupiter (Afghanistan). When one considers the great need there was for the camel in Tripolitania and in the Sahara. The camel reached Sudan some time before Christian era, and not before. Its absence from the numerous early rock-drawings which, so richly record the desert fauna, both wild and domestic, does not show this animal.
The introduction of domestic animals is so often associated with the migration of peoples and it is perhaps more than a coincidence that the first appearance of the camel in North Africa is closely synchronized with the first arrival of the Zenata Arabs. These nomadic people of Arabia came from the Middle East by way of Libya, and it seems probable that the Zenata were responsible for bringing the camel into general use through Gaetulia (Tripolitania) and the steppes of the High Plateaus around the third century B.C.
Other mammals of the desert
The Oryx algazal is a big antelope, roaming in a reduced belt of the Moroccan Sahara. The algazal is not a real animal of the desert, but it shows a remarkable resistance to thirst and could live without water, enjoying only of the monsoon of the high steppes. The other big antelopes of the Sahara are the Dama and the Dorcas of the southeastern dunes. The striped hyena of the arid steppe and the fennec fox of the high sandy dunes are the other kind of animal which could stand long days without water.
Animals using metabolic water
Most of the rodents of the desert, such as the Fat sand rat, the Rozet’s elephant and the Jerboa, drink no water and could be kept, easily, in captivity and fed only on dry food, without any risk for their heath, (Schmidt-Nielsen (1954). Nevertheless, the body of these animals contains as much water as any other mammals, and like them, they continually drain water, through breath and urinating. This water is exclusively produced by the organism through the oxidation process of food. A low limited quantity in water could be enough for these rodents if, on the other side, food is low in proteins; as these elements cause the building of large quantities of nitrate scraps. The low grants in water is compensated, on the other hand, by a complex mechanism of water saving. The rodents of the desert lose only half the water lost by any rodent of the temperate zones, as they excrete low quantities of concentrated urine and dry excrements. Beside the rodents, many other animals living in the arid regions are endowed with natural mechanisms for saving water, essential their physiological adaptation to dryness. Nocturnal activity, burying during the day, or during droughty periods, do also play a role of survival in the desert. Most desert animals have become nocturnal in order to survive. Some mammals would leave their dens or burrows after dusk. The Jerboa rat is entirely nocturnal, and after sealing the entrance to its long burrow, sleeps through the day.
The sun-stroke effects in the desert
The desert captures 90 percent of solar radiation, of which only 10 percent is reflected back by the dust of the atmosphere. In humid regions, 20 percent is reflected by clouds, 10 percent by vegetation and 30 percent by the expanses of waters. There are three factors, difficult to dissociate in solar radiation: thermal, chemical, and luminous factors. The effects of heat are most apparent in fauna. The temperature in the desert produces a double outcome, attaining high picks of almost 58 degrees C in the shade, and could fall dramatically to lower temperatures during the nights, especially in winter times. The magnitude’s variation between the nocturnal and the diurnal temperatures is, often, of about 30 degrees C. This is, of course, the temperature of the air, while that of the ground could reach temperatures of about 80 degrees C during the day, which might fall dramatically to about 20 degrees C during the night. The high temperature acts, at ground level, by reflection, and is not compatible with animal’s’ life. If typical animals of the desert were exposed directly to the sun, during the hot hours of the day, they would perish instantly.
Warm-blooded animals are endowed with regulating organs, which stabilize the temperature of their body to a level of 37 to 40 degrees C, beyond which it becomes risky if it increases by only 2 degrees. The animal’s organism, if exposed to the sun's radiation, would oppose any excess in temperature through sweating and gasping, which produces a certain cooling through lungs’ evaporation. The dromedary is endowed with a thermo-regulating mechanism that achieves internal temperature variations, which allows him to save water. Its temperature could reach 41 degrees C comfortably, and the animal would neither sweat nor gasp, and during the night he would reduce the temperature of his body to about 34 degree C. Normally, the temperature in the desert varies between ground and air by about 15 and 20 degrees C, and a lizard that seems indifferent to a temperature of 40 degrees C, would die in two minutes if lied to the ground under the same temperature.
Man and the desert
Man is not adapted to desert life, and if left without water, under a temperature of 50 degrees C, he would die in one or two days. Even if he was granted three litters of water a day, he would not survive, under such temperature, more than one week. However, men inhabited the entire grand desert expanse since prehistory. The only difference observed between the inhabitants of the desert concerns, particularly, the different techniques of adaptation to climatic conditions. It is true, that a highly pigmented skin offers a better shield against the ultraviolet sun radiation, but individuals with light pigmented skin could also tolerate life in arid tropical zones, if they are not exposed directly to the sun’s radiation. The human body is able to achieve physiological corrections during his acclimatization: the sweat glands would decrease their secretion, kidneys would slow the loss in salt, but no mechanism could really prevent the loss in water.