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MARGINALIA

We Are All Africans

Pat Shipman

Idaltu Means "Elder"

This past June, an international team headed by Tim White and F. Clark Howell of the University of California at Berkeley, and Berhane Asfaw of the Rift Valley Research Service in Addis Ababa announced the discovery of three fossilized human skulls in the Herto Bouri area of Ethiopia. Volcanic layers immediately above and below the layer were dated to 154,000 and 160,000 years using radioisotopes, meaning that the owners of the skulls lived sometime between those dates.

The most remarkable of the three specimens is an adult male cranium: With the exception of a few missing teeth and some damage on the left side of the skull, the fossil is complete. There is also part of another male skull and an immature cranium from a six- or seven-year-old child.

Once these specimens were cleaned and pieced together, the team was able to make some telling observations. Like modern humans, the owners of these skulls had small faces tucked under capacious braincases, making the facial profile vertical. The cranial volume of the most complete specimen, designated BOU-VP-16/1, is 1,450 cubic centimeters—large even for modern humans. The braincase of the other adult skull may have been even bigger. Although the African Herto skulls are longer and more robust than those of recent humans, the team considers the Herto specimens to be the earliest modern Homo sapiens yet found—direct ancestors of people living today. In an unknowing echo of Tishkoff's genetic findings, Tim White concludes, "We are all, in this sense, Africans."

Because the discoverers of the Herto skulls were unable to find convincing links between these fossils and archaic humans from any single geographic region, they put the three specimens into a new subspecies, Homo sapiens idaltu. The subspecies name idaltu comes from the Afar language of Ethiopia. It means "elder."

Figure 2. A close-up view of the reconstructionClick to Enlarge Image

Even paleoanthropologists who were not associated with the finds overwhelmingly agree that the Herto skulls are the earliest securely dated modern humans yet found, meshing with the Out of Africa hypothesis. The Herto fossils also fit neatly into an African succession: Older skulls from the region include Homo erectus fossils from Daka, dated to about 1 million years ago, and the archaic Bodo skull, estimated to be about 500,000 years old. Meanwhile, fossils from Omo Kibish, also in Ethiopia, are more recent than the Herto skulls, according to a reanalysis of those remains. For a long time, the Omo Kibish specimens were regarded as ambiguous: They were fragmentary, making their anatomy less clear, and the site was originally dated using older, less reliable methods. However, a recent relocation of the site turned up new pieces that glued onto specimens found in 1967, and the site was re-dated to about 125,000 years using modern techniques. Further evidence comes from the Qafzeh site in Israel—on a plausible route from Africa—where there is a 92,000-year-old modern human skull.

These findings establish the earliest modern humans in Africa, but they do not exclude the simultaneous evolution of modern man in other parts of the world, as suggested by the Multiregional hypothesis. The most pertinent test of Multiregionalism focuses on Neandertals, which are a uniquely European form of primitive humans. According to Multiregionalists, Neandertals (which lived between about 200,000 and 27,000 years ago) are a transitional form that connects European Homo erectus to modern Homo sapiens sapiens. Could the Herto skulls simply be the regional, African equivalent of Neandertals?

"No," says co-leader Berhane Asfaw definitively. "The Herto skulls show that people in Africa had already developed the anatomy of modern humans while European Neandertals were still quite different." Indeed, the Herto skulls, though robust, lack many of the diagnostic anatomical features of Neandertal skulls. Asfaw states, "We can conclusively say that Neandertals had nothing to do with modern humans based on these skulls and on the genetic evidence."








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