[Part 1 of 4] The really original aspect of the North African prehistoric cultures is evident not on the Mediterranean coast, but in the Sahara, in the highlands of Tibesti and Tassili, the Hoggar and west to the Atlantic coast. In these areas, and to a lesser extent in Kabylia and the Saharan Atlas, are found numerous elaborate rock carvings and paintings. From these we can deduce much, not only about the economy of the people which produced them, but also about their social organization. At the beginning of the Neolithic period the climate of this area was radically different from modern conditions. Although it certainly did not resemble a tropical jungle, it was much wetter than in historic times. The chain of depressions running across the southern Sahara was filled with shallow lakes, while the highlands were forested. A Neolithic civilization combining fishing with stock raising grew up here whose connections are far closer to the Sudan than to the Caspian to the north. The people were negroid, as both of their rare skeletons and the splendid frescos they painted on the cliffs of the Tassili range demonstrate. Their economy was largely pastoral, and many of the frescos show large herds of cattle. At some time, perhaps around the end of the second millennium, frescos begin to show elongated white men with characteristic long hair and pointed beards. Some confirmation of this racial shift comes from physical anthropology, although the skeletons seem to show closer resemblance to groups from the upper Nile Valley than to contemporary material from the Maghreb.
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