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Out of Africa and into Russia Monday, 15 January 2007
Agençe France-Presse
An artist's rendering of the the Hofmeyr skull, discovered in South Africa in 1952. Recent dating puts the skull's age at about 36,000 years. Image: Luci Betti-Nash
Modern humans may have spread out of Africa only relatively recently, suggest new Russian fossil finds and analysis of a fossil skull discovered over 50 years ago.
The 'Out of Africa' scenario of human evolution suggests that humans left Africa and spread throughout the rest of the world beginning only about 50,000 years ago. However, until now only a few hominid fossils and artefacts had emerged to explain when the great trek began and how humans dispersed.
An international research team, delving into Kostenki, a site of ancient volcanic ash on the River Don in Russia around 400 kilometres south of Moscow, found teeth, stone and ivory tools that suggest Homo sapiens moved there between 45,000 and 42,000 years ago.
The finds at Kostenki include perforated shell ornaments that can be traced to the Black Sea more than 500 kilometres away, and a carved piece of mammoth ivory that appears to have been shaped into a small human figure.
If so, it could represent the earliest piece of figurative art in the world. The stones used to make these artefacts were imported from sites between 100 and 180 kilometres away.
"The big surprise here is the very early presence of modern humans in one of the coldest, driest places in Europe," co-researcher John Hoffecker of the University of Colorado in Boulder, told the U.S. journal Science, which published the research on Friday. "It is one of the last places we would have expected people from Africa to occupy first."
Another paper, also appearing last week in Science, recounted how scientists used high-tech optical scanning and uranium dating methods to reassess a skull found in 1952 near Hofmeyr in South Africa.
The fossil is calculated to be 36,000 years old, plus or minus 3,300 years, making its original owner a near-contemporary of the Kostenki people. Some of the skull's features are "archaic", meaning that they are consistent with the crania of Eurasians from the Upper Palaeolithic era rather than of humans today.
The Upper Palaeolithic, or Old Stone Age, lasted from around 40,000 years ago to 10,000 years ago. It is considered a key period in human evolution, coinciding with the emergence of new stone tools, weapons and cave paintings.
"It just shows how superficial racial differences are; the speed at which they develop," said Alan Morris, a University of Cape Town researcher. "[If Hofmeyr man] came and sat beside you on a bus, you wouldn't bat an eyelid. You might glance out of the corner of your eye and wonder where he came from."
Anatomically modern humans are thought to have appeared in sub-Saharan Africa around 200,000 years ago. East Africa's Rift Valley, where H. sapiens remains dating back 160,000 years have been found, is widely considered the birthplace of modern man.
If the dating of the Hofmeyr skull is right, it means our forebears headed south out of the Rift Valley as well as north, migrating to southern Africa as well as to the Middle East and Eurasia.
Another possibility is that the cradle of H. sapiens is southern Africa, and that the migration was all northbound - although there is no fossil evidence to support this.
Apart from some early sites in the Middle East, until now the oldest evidence of modern humans outside of Africa has been in Australia, from around 50,000 years ago, according to Hoffecker.
Of the migration to Europe, Morris said there were several movements, "probably small family groups," that began around 90,000 years ago. The migration stopped for a while, resumed about 40,000 to 50,000 years ago, followed by "a very dramatic intrusion into central and western Europe, about 30,000 to 40,000 years ago."
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Out of Africa: Human odyssey is traced through DNA
Feb 20, 2008
PARIS (AFP) — Diving deep into the human gene pool, scientists in the United States have drawn one of the most detailed maps to date of our evolutionary past.
Their findings are detailed in two studies published Wednesday in the British journal Nature.
One paper reveals that human genetic diversity decreases the further one gets from Africa, the cradle of humanity.
People of African descent are more varied genetically than Middle Easterners, who are in turn more diverse than either Asians or Europeans, the study found.
By the time Homo sapiens migrated to the Americas across the Bering Straits, diversity had dwindled even further.
The other investigation shows that Americans of European descent have more potentially damaging mutations in their DNA than African-Americans, a finding that settles a long-standing debate.
It is now clear, the researchers say, that all persons of European descent, and not just isolated geographic groups, experienced a "genetic bottleneck" -- probably between 30,000 and 100,000 years ago -- as a small, founding population moved into present-day Europe.
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SEEKING - If you are interested in this sort of thing, you might want to research - Grimaldi, Mal'ta and Afontova Gora-Oshurkovo - Russia, Pachmari Hills – India. Then you can work your way to Catal-Huyuk Turkey. Also the Nigeritos. And ALWAYS keep your eyes open for artifacts with really big "BUTTS". That is the signature of Grimaldi, (the first Humans in Europe).
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