Rewriting Prehistory

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According to ancient tradition, the Chinese were savages until a sage came along and taught them how to construct shelters. Later wise men taught, in succession, the use of fire, music and the cultivation of crops. The last of these sages was the Yellow Emperor Huangdi, the father of Chinese civilization. That tale, from the first century B.C., suggests that the process of human evolution took place in China--a notion that was boosted by the celebrated discovery in 1921 of Peking Man, a Homo erectus fossil unearthed outside Beijing. That led to claims, believed for decades in China, that Chinese were the earliest modern humans.These days, the claims are getting a rough shaking from hard science--as is the notion that the Chinese are a unique, indigenous race. The Chinese Human Genome Diversity Project, a collaboration among 12 researchers from seven institutions, scrutinized DNA samples from 28 of China's 56 ethnic groups and then compared the samples with genetic material from other Asian and non-Asian groups. Their verdict: Chinese--like the rest of humanity--evolved in Africa. They migrated eastward along the Indian Ocean and made their way to China via Southeast Asia. It is now safe to conclude, reported the researchers, that modern humans originating in Africa constitute the majority of the current gene pool in Asian populations.
The project was inspired by similar research done in the mid-1980s at the University of California at Berkeley, where geneticists analyzed DNA from a range of ethnic groups and concluded that Homo sapiens descended from a common ancestral parent, whom they dubbed Eve, living in Africa 200,000 years back.

The Chinese researchers, led by Shanghai-born Jin Li, a professor at the Human Genetics Center at the University of Texas in Houston, studied genetic markers known as microsatellites, which are short segments of DNA known to change rapidly and distinctively over time. By comparing DNA microsatellites from Chinese, East Asian, African and other races, they came up with an evolutionary pedigree and even a time frame for various DNA alterations. Their theory is that modern humans entered China from the south 40,000 to 60,000 years ago.

That contradicts old theories revolving around Peking Man. The Homo erectus specimen, discovered in the Zhoukoudian cave in the suburbs of Beijing, is estimated to have lived 500,000 years ago; Homo erectus was the precursor to Homo sapiens. Peking Man's discovery made possible the idea that the missing link between the two species evolved in China--which the genetic theory flatly rejects.

But laboratory evidence isn't everything, according to Wu Xinzhi, professor at the Chinese Academy of the Sciences' Institute of Vertebrate Paleontology and Paleoanthropology in Beijing, who is one of China's foremost scholars on early humans. The septuagenarian Wu has conducted decades of research into the issue of early Chinese humans and says there are many strong challenges to the theory, which was first released in 1998. If Homo sapiens migrated to China, Wu says, he would have brought more advanced tools, similar to those found in Middle Eastern excavations. With one exception, no such tools have been found.

Wu plucks a skull specimen from a bookshelf of his Beijing office and ticks off the distinctive features of the various prehistoric Homo sapiens skeletons unearthed in China: Their face is comparatively flat, their nose is flat, the upper front teeth are shovel-shaped. Up to 90% of modern Chinese have such facial features, he says. If I stand at the gate of the United Nations building, says Wu, I can correctly identify a Mongolian, a European, an African. Why? His contention: the theory that Homo sapiens migrated outward from Africa may be true in Europe, but China went through a different evolutionary process. The theory is definitely wrong in China, he insists. For the modern human origins in China and the Oriental region, continuity is the main trend and hybridization (immigrants interbreeding with indigenous people) is subsidiary.

Wu admits he's no geneticist but he says Jin and his team should pay more attention to hard materials, not just soft ones. He also concedes that paleontologists have yet to unearth any Homo sapiens remains older than 50,000 years, which lends credence to the genetic theory. The government is allocating more money in the search for such evidence. But its main interest, says Wu, is in earlier remains--earlier than 2 million years. Such remains might cast light on earlier evolution, but if China wants to prove that humans evolved uniquely on its soil, it will have to cast its net closer in time--and find the missing evidence.

Reported by Jaime A. FlorCruz/Beijing