gems, ancient history, Africa

Today, all authorities agree that the Sahara experienced a humid climate during the six to eight millennia preceding around 2000 BC; during this period, vast lakes—such as the immense ‘Mega-Chad’—covered large portions of what is now arid desert, with Mega-Chad once spanning over 330,000 sq km at the 325 m contour compared to the modern Lake Chad’s mere 25,000 sq km bounded by the 282 m contour, though the true lowest point of the basin in Djourab lies at just 165 m above sea level; the presence of these ancient lakes is confirmed by radiocarbon-dated diatom deposits, remains of aquatic and terrestrial animals, and rich Stone Age human habitation sites, and these favorable environmental conditions supported a wide array of fauna—including elephants, giraffes, rhinoceroses, antelopes, and hippopotamuses—across regions now entirely desert, such as the Ténéré, Tanezrouft, and Majābat al-Kubrā, where numerous Neolithic archaeological sites have been discovered and many rock surfaces bear images of this once-thriving ‘Ethiopian’ fauna, with Saharan populations during this period living as hunter-gatherers and, in some areas, also practicing fishing.