Human Family (IMAGE) Columbia Climate School Caption At Nairobi's Kenya National Museum, two Homo sapiens visit the skeleton of Turkana Boy, member of a precursor species known as Homo erectus. By his time, some 1.6 million years ago, the east African landscape was largely dominated by grasses. Credit Kevin Krajick/Lamont-Doherty Earth Observatory Usage Restrictions Credit must be given. 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.