Sahara
From Wikipedia, the free encyclopedia.
- For other uses, see Sahara (disambiguation).
The Sahara is the world's second largest desert (second to Antarctica), over 9,000,000 km² (3,500,000 mi²), located in northern Africa and is 2.5 million years old. The entire land area of the United States of America would fit inside it. Its name, Sahara, is an English pronunciation of the word for desert in Arabic (صحراء arabic pronunciation ▶(?)).
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Overview
The boundaries of the Sahara are the Atlantic Ocean on the west, the Atlas Mountains and the Mediterranean Sea on the north, the Red Sea and Egypt on the east, and the Sudan and the valley of the River Niger on the south. Sahara is divided into western Sahara, the central Ahaggar Mountains, the Tibesti massif, the Aïr Mountains (a region of desert mountains and high plateaus), Tenere desert and the Libyan desert (the most arid region). The highest peak in the Sahara is Emi Koussi (3415 m) in the Tibesti Mountains in northern Chad.
The Sahara divides the continent into North and Sub-Saharan Africa. The southern border of the Sahara is marked by a band of semiarid savanna called the Sahel; south of the Sahel lies the lusher Sudan.
Humans have lived on the edge of the desert for almost 500,000 years. During the last ice age, the Sahara was a much wetter place, much like East Africa, than it is today. Over 30,000 petroglyphs of river animals such as crocodiles survive in total with half found in the Tassili n'Ajjer in southeast Algeria. Fossils of dinosaurs have also been found here. The modern Sahara, though, is generally devoid of vegetation, except in the Nile Valley and at a few oases and in some scattered mountains and has been this way since about 3000 BC.
2.5 million people live in the Sahara, most of these in Mauritania, Morocco and Algeria. Dominant groups of people are the Tuareg-Berber, the Sahrawis, Moors, and different black African ethnicities including the Tubu, the Nubians, the Zaghawas and the Kanuri. The largest city is Nouakchott, Mauritania's capital. Other important cities are Tamanrasset, Algeria; Timbuktu, Mali; Agadez, Niger; Ghat, Libya; and Faya, Chad.
History
Morocco boasts the oldest figurine known to date: 300,000 to 500,000 years ago.
Algeria has provided evidence of remarkable workmanship in tool-making as early as 30,000 BC. According to some sources, prehistoric Algeria was the site of the highest state of development of Middle Paleolithic flake-tool techniques. Early remnants of hominid occupation have been found in Ain el Hanech, near Saïda (ca. 200,000 B.C.). Later, Neandertal tool makers produced hand axes in the Levalloisian and Mousterian styles (ca. 43,000 B.C.) similar to those in the Levant. Tools of the era starting about 30,000 BC are called Aterian (after the site Bir el Ater), south of Annaba in the north-eastern corner of Algeria, and are marked by a high standard of workmanship, great variety, and specialization. See Prehistory of Central North Africa.
Bubalus Period
(35,000 - 8,000 BC): Remains show artistic stone engravings, petroglyphs and pictographs made of pigment mixed with milk of animals that became extinct in the area, including the buffalo (Bubalus antiquus), elephant, rhinoceros, and hippopotamus. This is mainly found in the southeastern area of modern Algeria, Chad and Libya. Men often wearing round helmets (10000 BC - 8000 BC) are armed with clubs, throwing sticks, axes and bows, but never spears. A grain-grinding culture farming along the Nile around 9500 BC used the earliest known type of sickle blade.
Archaeological findings indicate occupation in Nabta Playa, located in the Nubian Desert of southern Egypt, dating to somewhere between the 10th and 8th millennia BC [1]. Evidence also indicates human habitation in the southwestern corner of Egypt, near the Sudan border, before 8000 BC. Climate changes and/or overgrazing around 8000 BC began to desiccate the pastoral lands of Egypt, eventually forming the Saharan desert, and early tribes naturally migrated to the Nile river where they developed a settled agricultural economy and more centralized society.
Archaeological finds also show that the Nabta peoples, between the 10th and 8th millennia BC, were herding domesticated cattle and using ceramics adorned by complicated painted patterns created perhaps by using combs [2].
A pottery fragment of a large bowl that was discovered in Bir Kiseiba in southern Egypt has been dated to between 8000 BC and 7000 BC [3].
Cattle Period
(7,500 - 4,000 BC): This period marks the onset of an extensive pastoral economy: domesticated cattle, sheep and goats. Domesticated animals are Asian imports. Pottery making becomes more prevalent, as well as manufacturing of polished stone axes, grindstones and arrowheads, and the predominant use of bow and arrows for hunting. There is also evidence of cereal cultivation in the East Sahara in the 7th millennium BC.
Villages support large populations and cattle herding. By the 7th millennium BC exceedingly large and organized settlements are found in Nabta Playa, along with deep wells that could supply water year-round [4] and huts lined up in straight rows [5]. Sustenance in Nabta Playa in this era depended upon cattle herding, fruit, legumes, millets, sorghum and tubers [6], but evidence shows only seasonal occupation of the Nabta Playa region.
Goats and sheep also appear in Nabta Playa in the late 7th millennium BC, apparently having also been imported from Southwest Asia [7]. In this era, numerous large hearths also are found in Nabta Playa [8].
Interestingly, the domestication of the pig (see [9]) in the Sahara and ancient Egypt has been cited as a likely primary contributor to the desertification of the Sahara (see Sahara Desert (ecoregion)).
By 6000 BC predynastic Egyptians in the southwestern corner of Egypt were herding cattle and constructing large buildings. Subsistence in organized and permanent settlements in predynastic Egypt by the middle of the 6th millennium BC centered predominantly on cereal and animal agriculture: cattle, goats, pigs and sheep [10]. Metal objects replaced prior ones of stone [11]. Tanning animal skins, pottery and weaving are commonplace in this era also [12]. There are indications of seasonal or only temporary occupation of the Al Fayyum in the 6th millennium BC, with food activities centering on fishing, hunting and food-gathering [13]. Stone arrowheads, knives and scrapers are common [14]. Burial items include pottery, jewelry, farming and hunting equipment, and assorted foods including dried meat and fruit [15]. The dead are buried facing due west [16].
By the 6th millennium BC, evidence of a prehistoric religion or cult appears in Nabta Playa, with a number of sacrificed cattle buried in stone-roofed chambers lined with clay [17]. Other subterranean complexes are also found, including evidence of an early attempt at sculpture [18].
World's earliest known astronomy
By the 5th millennium BC the peoples of Nabta Playa had fashioned the world's earliest known megalithic astronomical device, 1000 years older than but comparable to Stonehenge. Research shows it to be a prehistoric calendar that accurately marks the summer solstice [19].
Archaeological discoveries reveal that the Nabta Playa peoples led livelihoods seemingly at a higher level of organization than their contemporaries who lived closer to the Nile Valley [20]:
- above-ground & below-ground stone chamber construction,
- villages designed in pre-planned arrangements,
- deep wells that held water year-round.
Analysis of human remains in Nabta Playa provide evidence of migration from sub-saharan Africa [21].
Berber Period
(3,000 - 700 BC): The early period shows the importation of horses, camels and milking cows and large scale agriculture. The use and forging of iron came about from trade with the Phoenicians (c. 1220 BC). They created a confederation of kingdoms across the entire Sahara to Egypt, generally settling on the coasts but sometimes in the desert also.
By 2500 BC the Sahara was as dry as it is today and it became a largely impenetrable barrier to humans, with only scattered settlements around the oases, but little trade or commerce through the desert. The one major exception was the Nile Valley. This well watered section of the desert became one of the most densely populated regions on the planet and the home to one of humanity's earliest civilizations. The Nile, however, was impassable at several cataracts making trade and contact difficult. Over time Egypt spread south and technologies such as iron working, and perhaps ideas such as that of monarchy spread into Nubia and further south.
Sometime between 633 and 530 BC Hanno the Navigator either established or reinforced Phoenician colonies in the Western Sahara, but all ancient remains have vanished with virtually no trace. See History of Western Sahara.
By 500 BC a new influence arrived in the form of the Greeks and Phoenicians. Greek traders spread along the eastern coast of the desert, establishing trading colonies along the Red Sea coast. The Carthaginians explored the Atlantic coast of the desert. The turbulence of the waters and the lack of markets never led to an extensive presence further south than modern Morocco. Centralized states thus surrounded the desert on the north and east; it remained outside of the control of these states. Raids from the nomadic Berber people of the desert were a constant concern of those living on the edge of the desert.
The greatest change in the history of the Sahara arrived with the Arab invasion that brought camels to the region. For the first time an efficient trade across the Sahara desert could be conducted. The kingdoms of the Sahel grew rich and powerful exporting gold to North Africa. The emirates along the Mediterranean sent south manufactured goods and horses. From the Sahara itself salt was exported. This process turned the scattered oasis communities into trading centres, and brought them under the control of the empires on the edge of the desert.
This trade persisted for several centuries until the development in Europe of the caravel allowed ships, first from Portugal but soon from all Western Europe, to sail around the desert and gather the resources from the source in Guinea. The Sahara was rapidly remarginalized.
The colonial powers also largely ignored the region, but the modern era has seen a number of mines and communities develop to exploit the desert's natural resources. These include large deposits of oil and gas in Algeria and Libya and large deposits of phosphates in Morocco and Western Sahara.
mtDNA analyses (see Z. Brakez et al., "Human mitochondrial DNA sequence variation in the Moroccan population of the Souss area" extract) found that various populations have contributed to the present-day gene pool of the Souss region of southern Morocco, including Berbers, Arabs, Phoenicians, Sephardic Jews, and sub-Saharan Africans. Throughout the Sahara, Berbers, Arabs, and sub-Saharan Africans are significantly represented genetically.
See also
- Richat Structure
- Western Sahara
- Desertification
- Trans-Saharan trade
- Arabian-Nubian Shield
- Nile
- Red Sea
External links
- Trans-Sahara routes
- Google Satellite image of the Sahara (Northern Africa)
- Sahara pictures from Algerian UN Permanent Mission website
References
- Michael Brett and Elizabeth Frentess. The Berbers. Blackwell Publishers. 1996.
- Hugh Kennedy. Muslim Spain and Portugal: A Political History of al-Andalus. Longman, 1996.
- Abdallah Laroui. The History of the Maghrib: An Interpretive Essay. Princeton, 1977.
- Charles-Andre Julien. History of North Africa: From the Arab Conquest to 1830. Praeger, 1970
