Posted on 01/02/2003 11:03:24 AM PST by blam
Chinese Roots: Skull may complicate human-origins debate
Bruce Bower
In 1958, farm workers digging in a cave in southern China's Liujiang County discovered several human bones including a skull. Relying on its resemblance to securely dated human fossils in Japan, scientists assigned this Homo sapiens skull an age of 20,000 to 30,000 years.
ASIAN CONNECTION.
If southern China's Liujiang skull is really more than 100,000 years old, this modern Homo sapiens fossil will shake up theories of human evolution. W. Wang
However, the Liujiang finds may be much older than that, according to a report in the December Journal of Human Evolution.
The fossils probably came from sediment dating to 111,000 to 139,000 years ago, says a team led by geologist Guanjun Shen of Nanjing (China) Normal University. He and his coworkers add that it's still possible that the Liujiang discoveries came either from a cave deposit dating from around 68,000 years ago or from one dating to more than 153,000 years ago.
If any of these estimates pans out, "the Liujiang [specimen] is revealed as one of the earliest modern humans in East Asia," the team concludes. The presence of modern humans in this part of the world 100,000 years ago or more would roughly coincide with their earliest fossil dates in Africa and the Middle East.
Evidence of such ancient roots for H. sapiens in China creates problems for the influential out-of-Africa theory of human evolution, Shen's group says. That theory holds that modern humanity originated in Africa between 100,000 and 200,000 years ago and then spread elsewhere, replacing other Homo species. If the Liujiang dates were confirmed, out-of-Africa adherents would need to find older African H. sapiens fossils than they now have or show that modern humans migrated extremely quickly from Africa to eastern Asia.
The new dates also suggest that other, more-primitive-looking Chinese Homo fossils that date to 150,000 to 100,000 years ago represent a lineage that coexisted with modern humans, Shen proposes.
Scientific accounts from 1959 and 1965 of the Liujiang discoveries guided the new determination of the fossils' likely burial site. Shen's team mapped various soil deposits in the cave and calculated the age of crystallized limestone samples by using the rate of uranium decay.
Uranium analyses at other sites support an ancient origin of modern humans in southern China, Shen says. H. sapiens teeth found at two other caves in this region come from sediment that his group dates to at least 94,000 years ago.
Anthropologists with divergent views about human evolution say that the new age estimate for the Liujiang skull remains preliminary. It's still uncertain how the skull got in the cave and where it was originally buried, remarks Christopher B. Stringer of the Natural History Museum in London. Stringer, an out-of-Africa proponent, says that Shen's team members need to date either the skull itself or the calcite clinging to its surface to make their case.
Milford H. Wolpoff of the University of Michigan in Ann Arbor agrees. "I'd love for the Liujiang skull to be as old as Shen proposes, but we'll never know for sure without directly dating the specimen," Wolpoff holds. In his view, modern humanity evolved simultaneously in Africa, Asia, and Europe over the past 2 million years.
Shen says he hopes to work out an agreement with Chinese officials in charge of the Liujiang skull to date the specimen directly.
I am not a big banger, like Blam, but I do believe that if you take a close look at the evidence central Asia is the place.
;-)Thanks for the ping.
At some point, human ancestory can be traced to Africa. Australiopithecus and Homo Habilis for sure. I think various Homo Erectus evolving into the various races of Homo Sapiens is a compeling theory, I even believe it is more likely than not, but this discovery hardly disputes OOA. If any single group of humans wandered persuing game, than it is very likely that within only a few thousand years they may have well migrated 10,000 miles. Certainly at this time there were huge migration of fauna--horses and camels to the old world, bison and elephants to the new. Has anybody postulated how long it took for horses to appear in say, Spain, or Asia Minor, as opposed to Tibet or China?
But humans are obviously capable of migrating extremely quickly. It's entirely possible for a nomadic group of humans to travel from Africa to eastern Siberia and back again by way of Scandanavia in far less than a single human lifetime; all that's needed is the desire to do it. To me, it seems highly unlikely for some long-distance travel not to have happened.
Of course, this neither supports nor refutes the "Out-of-Africa" hypothesis. What it means is that some of the most important migrations may well have happened too quickly to have left any trace. "Out-of-Africa" and "evolved everywhere" may be indistinguishable. It might as easily have been "Out-of-India".
Peking Man was Homo erectus.
I'd be very skeptical about any date in the region of 100,000 years that wasn't accompanied by first rate archaeological and dating techniques. Carbon dating is essentially impossible at that age, and uranium dating imprecise. Indeed, the idea that Europeans, Asians and Africans may have diverged far earlier is intriguing, and would drive the 'race is mythical' people bonkers; since we consider H. erectus a different species from H. sapiens, then consistency would demand the (at least) three distinct descents from H. erectus be three distinct species. I can't think of anything more politically incorrect, offhand. :-)
However, the preponderance of the evidence does still seem to support 'Africa first'. If you push the divergence date back to 1/4 million years, you have to assume we all evolved from Homo erectus almost in perfect parallel; typical Mongoloids, Caucasoids and Negroids are far more similar to each other than to H. erectus or even H. neanderthalensis.
I don't have a 'ping' list, I just ping whoever I happen to remember, lol.
I believe Victor Mair covers that in his book The Tarim Mummies.
Toba fills that requirement. Many believe only 2,000-5,000 humans worldwide survived this catastrophe.
Well, there were many Nubian queens of Egypt, such as Nefertari, as the Nubians invaded Egypt and ruled for many years. However, Cleopatra was of Greek blood.
But a single common ancestor (e.g., a "mitochondrial Eve") doesn't necessarily imply a genetic bottleneck. It's possible that a (mutant) woman was born with significantly superior mitochondria, which slowly over time supplanted the other mitochondria throughout a large and sustained population with an otherwise diverse gene pool, without the need for a mass die-off, or for one population pushing out another. (This could similarly work for any given chromosome.)
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