Most likely, a change in climate helped to push them out. Experts suggest that droughts in Africa led to starvation, and humans were driven to near extinction before they ever had a chance to explore the world. A climate shift and greening in the Middle East probably helped to draw the first humans out of Africa.

There are 54 countries in Africa today, according to the United Nations. The full list is shown in the table below, with current population and subregion (based on the United Nations official statistics).

Brain drain is reported to have direct negative impacts on the population's health status in the donor country, with associated consequences for the productivity and welfare of the population. Many African countries face huge losses of human skills, and this, in turn, has affected their development.