Over the course of 5000 years, the amount of rain falling over the Sahara drastically decreased. As most of the Sahara is towards the North and mostly inland, it means that less water falls there. The Sahara is huge, covering ~9,000,000 square kilometers. It is called Sahara, because that is translated into desert. The Sahara is mainly stone plateaus, sand seas, and mostly sand dunes. Wind and little rain shapes most of the desert features. Because of this, the area has little suitable places to farm, has little vegetation, and the little vegetation it has consists of shrubs and little grasslands. The place is extremely hot during the days, and has a dramatic contrast during the night. Because of all this, many people that saw that the desert is a harsh area to live in, try to move closer to plains and forests that are still inside Africa. This led to a spread of people from Northern Africa to other parts of the land.
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