The African Humid Period, known popularly as the ”Green Sahara”, occurred in the more northerly zones of the continent between circa 14,700 and 5,500 years ago. At the 5.5 ka threshold, the human populace of the area buckled, succumbing to the effects of planetary orbital shift and the resulting climatological change to the environment. Human intervention, due to the practice of pastoralism, delayed this inevitable decline of sustainable life supporting systems by approximately a half millennium. Remnants of these people and various animal populations ventured eastward toward the Nile.
”Humans did not accelerate the decline of the 'Green Sahara' and may have managed to hold back the onset of the Sahara desert by around 500 years, according to new research led by UCL.
The study by a team of geographers and archaeologists from UCL and King's College London, published in Nature Communications, suggests that early pastoralists in North Africa combined detailed knowledge of the environment with newly domesticated species to deal with the long-term drying trend.
It is thought that early pastoralists in North Africa developed intricate ways to efficiently manage sparse vegetation and relatively dry and low fertility soils…”
Source
Dr. Troglodyte