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.

Ethiopia is the oldest independent country in Africa and one of the oldest in the world. What are believed to be the oldest remains of a human ancestor ever found, which have been dated as being some five million years old, were discovered in the Awash Valley in Ethiopia.

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.