Americans Developed in Africa, Why Then Won't America Develop Africa?

In a major discovery that may fill in the missing piece connecting us to our most immediate ancestors, the fossilized skulls of two adults and a child who lived in Ethiopia 160,000 years ago could represent the earliest known remains of modern humans, scientists reported Wednesday.

The bones show traits consistent with those of people living now. And in another link to contemporary humans, the remains show what may be the oldest documented instance of people saving and repeatedly handling the bones of their dead.

``It's a big pulse of new evidence in a period we didn't know well in Africa,'' said Tim D. White, a paleoanthropologist at the University of California-Berkeley and leader of an international team that discovered the fossils near the village of Herto, 140 miles northeast of Addis Ababa. ``This is marking of skulls, curation of skulls, that you only see in modern human society.''

Their report in the journal Nature fills a critical gap in the story of human evolution, according to experts in the field. Genetic studies indicate Homo sapiens, or modern-day humans, emerged about 150,000 years ago. But until now, there have been no human ancestral fossils between 600,000 and 100,000 years old whose ages and characteristics were firmly pinned down.

The discovery strengthens the argument that modern humans arose in Africa and spread from there to populate the world. It also supports the idea that Neanderthals, another hominid species, were an evolutionary dead end and did not intermingle with our ancestors.

And it raises a mystery: Why were only skulls found at this site, near what was once a shallow, freshwater lake full of catfish, crocodiles and hippos? In addition to the three skulls, fragments of seven other people were found, scattered among stone scrapers, cleavers and other tools and the remains of butchered hippos. All of the human remains were either teeth or bits of skull.

``We don't have a single toe bone of these folks,'' White said. ``We don't know what they were doing with the bodies.''

The team, which includes researchers from Ethiopia, Japan, Turkey and France, suggested that the Herto fossils represent a subspecies of the human race, which they call Homo sapiens idàltu. The last word means ``elder'' in the language of the Afar people who live in the area.

``This represents a lineage that ultimately gave rise to living humans,'' said William H. Kimbel, science director for the Institute of Human Origins at Arizona State University. ``It's a very important find.''

Richard Potts, director of the human-origins program at the Smithsonian Institution, said the discovery is ``very exciting. They indicate, I think, the earliest evidence of our species. They're right on the cusp, the transition between archaic species and modern species of humanity.''

He said the team's findings will also feed the debate about when people began to use language and other symbols and perform rituals such as caring for the dead, all hallmarks of modern behavior.

``Words don't fossilize, so we look for subtle clues in artifacts that archaeologists dig up, or in unusual behavior that may be symbolic,'' Potts said.

The Herto fossils were found in 1997 in an area known as the ``Middle Awash'' that had already yielded a trove of human ancestors, starting with a species known as Ardipithecus that lived 6 million years ago.

In 1997, while on the way to another area to dig, White noticed the fossilized bones of a hippopotamus protruding from the ground. He returned 11 days later. While he rigged a tarp to shade the team during lunch, Two members of the group wandered over to take a look at the hippo -- and spotted the human bones.

It took three years to remove, restore and clean the fossils, which were then compared to other ancient fossils and modern people.

All three skulls bore tool marks indicating that the heads had been cut from the bodies, and then the flesh cut and scraped away. The child's jawbone had been removed, the team reported, and some of the bone surfaces had been smoothed and polished, as if they had been frequently handled.

These marks are similar to those seen in skulls from New Guinea that have been cut and decorated as part of ritual, the team said, adding that it did not believe they were the result of cannibalism.

``This is 10,000 human generations in the past, so we're not going to have any direct continuity between those practices and ones today,'' White said. ``But this is the earliest evidence that people were sort of manipulating the dead'' long after death took place.



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