Hints: The Sahara over-cultivating savannah Ennedi Gorge the Nile

The Sahara , as we know it today, is only 2, 000 years old, the product of a rapidly drying climate in North Africa. But our ancestors also had a hand in this change. By over-cultivating marginal lands, and intensively grazing livestock. Before, things were very different. Try to imagine this land flooded by the ocean, swathed in forest and savannah, swept by mighty rivers.
Ennedi Gorge once fed a vast tributary of the Nile. Today all that remains are a few precious pools, crucial watering holes for passing caravans of camels. In just ten minutes of drinking , these remarkable animals can put on a third of their body weight in water. It's enough to carry them for well over 100 kilometers to the next oasis.

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