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8 | SCIENCE NEWS | September 8, 2012 www.sciencenews.org

Jewish Diaspora written in DNAGenetic analysis supports history of ancient migrations

New fossils hint at ancestral splitAfrican jawbone suggests two early species in human genus

By Bruce Bower

Newly discovered face and jaw fossils show that at least two species of the human genus Homo lived alongside each other in East Africa nearly 2 mil-lion years ago.

These new finds are a good match for a roughly 2-million-year-old Homobrain case and face excavated in 1972 in the same part of East Africa, reports a team led by anthropologist Meave Leakey of the Turkana Basin Institute in Nairobi, Kenya. Long considered a puz-zling exception among early Homo fi nds, the 1972 discovery features big bones and a flat, upright face. That fossil, together with the new fi nds, represents a new Homo species, Leakey and her col-leagues conclude in the Aug. 9 Nature.

Until now, researchers have found it difficult to exclude the possibility that the flat-faced fossil — known as KNM-ER 1470 — came from a male of the same species as smaller, early Homofi nds in East Africa.

“After so many years of questions about the identity of the enigmatic 1470 fossil, the chances that it’s from a sepa-rate species have greatly improved with our new discoveries,” says anthropolo-gist and study co author Fred Spoor of the Max Planck Institute for Evolution-ary Anthropology in Leipzig, Germany.

Members of Leakey’s field team unearthed the new fossils from 2007 to 2009 along the shore of Kenya’s Lake Turkana. Previously dated volca-nic ash layers at the site place the fi nds at between 1.78 million and 1.95 mil-lion years old. Further study is needed before assigning the early Homo fossils to particular species, Spoor says, and it’s unclear whether either species led to Homo erectus, which appeared about 1.7 million years ago, or to people living today. For now, he proposes only that at

By Tina Hesman Saey

Historical Jewish migrations out of the Middle East about 2,000 years ago can be traced through the DNA of people living in Africa today.

These distinctive genetic signatures bolster historical accounts, human genet-icist Harry Ostrer of Albert Einstein Col-lege of Medicine in New York City and colleagues report online August 6 in the Proceedings of the National Academy of Sciences. Their analysis included 509 people from 15 Jewish populations.

Jews settled in Tunisia more than 2,000 years ago, and DNA signatures car-ried from the Middle East are still evident in Tunisian Jews today, the researchers

least two Homo species inhabited East Africa nearly 2 million years ago.

Anthropologist Bernard Wood of George Washington University in Wash-ington, D.C., suspects that Leakey’s team has found fossil evidence for a new, early Homo species distinct from both the 1470 specimen, which he classes as H. rudolfensis, and other Homo fossils from that time, which he groups under H. habilis. The newly found face fossil, which belonged to a child about 8 years old, mirrors the shape of the adult 1470 face, Wood says. But the nearly com-plete lower jaw and partial lower jaw that Leakey’s team found fi t neither in H. rudolfensis nor in H. habilis, he says.

Spoor’s proposal that at least two species inhabited East Africa 2 million years ago goes too far, contends anthro-

pologist Tim White of the University of California, Berkeley. Too few early Homo fossils exist to rule out whether the new fi nds, and the 1470 specimen, fall within a single species that included substantial skeletal differences across individuals and between sexes, White says.

IN THE NEWS

Humans For longer versions of these and other Humans stories, visit www.sciencenews.org

found. Together with Libyan Jews, the Tunisian Jews form a separate branch from Moroccan and Algerian Jews.

Jews in Morocco and Algeria bear signatures characteristic of Sephardic Jews, who once lived in Spain and Portu-gal. After being expelled from the Iberian Peninsula in the late 15th century, some Sephardic Jews went to North Africa, car-rying their genetic heritage with them.

DNA signatures in Ethiopian Jews distinguish them from Middle East-ern Jews and from other people living in Ethiopia. The findings are consis-tent with historical accounts that local people were converted to Judaism, then spent more than 2,000 years in cultural and genetic isolation.

Though the new study is the most in-depth of its kind, it certainly doesn’t determine who is a Jew. “Genetics is only a facet of identity,” says Francesc Calafell, a population geneticist at the Institute of Evolutionary Biology in Barcelona.

A nearly 2-million-year-old lower jaw dis-covered recently in East Africa, along with other new fi nds, differs substan-tially from smaller, earlier discoveries of Homo fossils in the region.

humans.indd 8 8/22/12 1:46 PM