Homo Erectus in Africa

Hominids evolved in Africa yet today hominids are found on every continent. The Homo erectus was the first to leave Africa and they did so perhaps 700,000 to one million years ago. In recent years new findings and sources of evidence have led scholars to question this established answers. The first new information came from geochemist Carl Swisher, who in the mid-1990s redated the Java sites where Homo erectus fossils had been found and determined they dated to perhaps 1.8 million years ago. Since the earliest Homo erectus fossils in Africa share a sim­ilar date, this created a problem—how did Homo erectus appear in lava at about the same time they appeared in Africa? As this question was being pondered, a remark­able set of new Homo erectus fossils were being uncovered in Dimanisi, Georgia. Dated at 1.7 million years ago, these fossils made it clear that H. erectus left Africa al­most as soon as they had evolved. The discovery of a Homo habilis fossil at Dimanisi, and of Oldowan-like tools at Riwat, Pakistan and Loggupo, China, sug­gested that H. habilis may have been the first to leave Africa and H. erectus followed a path their predecessors blazed. If they were following an earlier migration, it could explain how H. erectus were able to move so quickly across Asia.

A more unusual source of information on when ho­minids first left Africa comes from the parasites that ac­companied them. All hominoids are plagued by lice, but humans host a distinct species, Pediculus humanus. Geneticist David Reed and his colleagues found that years ago—about the time the first hominids appeared. More interesting, however, Reed and colleagues discovered that there are two subspecies of P. humanus that appear to have diverged about 1.2 million years ago. One subspecies is found worldwide today, the other is restricted to the New World.

Questionnaire:

• Explain more about the Homo erectus in Africa
•  How did Homo erectus appear in lava at about the same time they appeared in Africa?