Population refers to the number of people living in a given area, country or continent. Causes of a large population are the following:

Adherence to African traditions which regard children as a sign of wealth.

High fertility rates of African women.

Early marriages and early child bearing. S

ome religions discourage the use of artificial family planning methods e.g. Catholicism. Low levels of education. The recognition and approval of the extended family system. Industrialization. Improved health services and nutrition. The increase in the rate of school dropouts. Refugee problems. Increased and unchecked immigration.
Effects

It leads to increased pressure on land.

It leads to unemployment problems.
It contributes to rural-urban migration. Development of slums. It leads to pressure on social infrastructure. It leads to increased dependence on foreign aid. It leads to an increased rate of dependants. It leads to increased crime rate. It leads to the over exploitation of natural resources. It contributes to deterioration in the standards of living. It leads to land fragmentation. It contributes to environmental degradation. It leads to urbanization. It contributes to economic development by providing market for goods. It provides the required labour force for agricultural and industrial growth.