Because the Sahel is experiencing less and less rainfall each year, what are many Africans having to do?

Since the 1970s the Sahel has experienced drought conditions on a regular basis. This is down to physical and human factors Overgrazing and deforestation on marginal land can lead to desertification  With less vegetation there is less transpiration and evaporation from the soil causing less rainfall

Explanation:

disease was the number one killer of native peoples. they had had little exposure to the diseases of europe. this led to some villages being almost completely wiped out and some tribes destroyed.