MONSOON rain, or rather the lack of it, precipitated the rise of great civilisations in what is now the Sahara desert.
Since prehistoric times people have been following the shifting monsoon rains around the Sahara, a practice that triggered the herding of livestock and even the development of the great pharaonic dynasties,say researchers who have re-examined archaeological sites across the region.
Rudolph Kuper and Stefan Kröpelin of the Institute of Prehistoric Archaeology at the University of Cologne, Germany, studied geological and ecological data for clues to patterns of past rainfall. They also examined radiocarbon dates of dwellings and artefacts…
