New Study of Early HumansBy George Grow
This is the VOA Special English SCIENCE REPORT.
A new American study is disputing the theory that all humans alive today developed from a single group of early humans. The study found that the ancestors of modern humans came from many different areas of the world, not just one.
Milford Wolpoff of the University of Michigan in Ann Arbor and other scientists organized the study. Their findings were reported in Science magazine.
The findings are the latest in the continuing dispute about how modern humans developed. Many scientists believe that all humans are genetically linked to a single group of ancient humans. They say that this group probably lived in Africa about one-hundred-thousand years ago.
Fossil remains show that other early humans were alive from this time back to almost two-million years ago. However, there is no more recent evidence of such creatures. Some scientists say this means that all the other early humans must have died out.
Mr. Wolpoff and other scientists question this theory. They believe that small groups of early humans traveled out of Africa over thousands of years. They traveled to Asia, Europe and even as far as Australia. They reproduced with a more ancient kind of human who already lived in those areas. They say there is little evidence that a small group from one area replaced the entire population of early humans.
In the new study, the scientists examined some of the earliest known fossils of modern humans. They examined the head bones of ancient humans from Australia and Europe. The bones are believed to be twenty-thousand to thirty-thousand years old.
The scientists compared these skulls with older Australian and European fossils. They also compared the skulls with even older fossils from Africa and the Middle East.
The scientists found that the Australian and European skulls were similar in appearance to the more ancient fossils from Africa and the Middle East. The skulls also were similar to more ancient remains from Australia and Europe. The scientists say there were many more similarities than could be explained by chance alone.
Mr. Wolpoff rejects the idea that what he calls one lucky group developed into early humans. He says the fossils clearly show that more than one ancient group survived and developed.
This VOA Special English SCIENCE REPORT was written by George Grow.