For many years the popular theory on the beginnings of the Sahara Desert which dates back 10,000 years was due to a shift in the Earth’s orbit, combined with some changes in the regions vegetation patterns.
Now however, researchers have a new theory. David Wright from the Seoul National University and his colleagues have put forward the theory that it could actually be due to the movements of early pastoral communities in the Nile Valley.
The introduction of livestock in the area some 8,000 years ago by the communities could have suppressed the blossoming of vegetation in the area, leaving the surface more exposed and reflective, and would have altered the atmospheric conditions. This would have greatly diminished the effect of seasonal monsoons in the region over time, having a roll-on effect and creating more exposed land. Over time, the effect would have greatly increased the desertification in the area.
“In East Asia there are long established theories of how Neolithic populations changed the landscape so profoundly that monsoons stopped penetrating so far inland,” said Wright.
“There were lakes everywhere in the Sahara at this time, and they will have the records of the changing vegetation,” Wright said. “We need to drill down into these former lake beds to get the vegetation records, look at the archaeology, and see what people were doing there.”