The Wall of Africa (IMAGE) University of Utah Caption This map shows the chain of highlands and mountain ranges that University of Utah geologists Royhan and Nahid Gani dub "the Wall of Africa." Higher elevations are shown in reddish tones and lower elevations in green and blue. The Ganis say most of this "wall" was uplifted during the past 7 million years, when humans and their ancestors evolved in Africa. Credit Nahid Gani Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.