Wushan Man

Is Africa the Only Birthplace of Man?

by Huang Wei

The growing achievements of Chinese archaeologists over the past decade or so have repeatedly challenged the traditional hypothesis that human species evolved in Africa. Many believe that human evolution was diversified, some even boldly suggest that Asia, instead of Africa, is the birthplace of mankind.

Chinese archaeologists have made significant discoveries over the past year in Anhui Province located at the mid-lower reaches of the Yangtze River, once again challenging the assumption that the human species first appeared in Africa, a theory which has long dominated the paleoanthropological world.

Prior to this, their numerous discoveries in relation to the Wushan Man (Homo erectus Wushanensis 2 million years ago) in the Three Gorges area at the middle reaches of the Yangtze River had already shaken the foundations of this traditional theory.

Early last year, the Study of Evolution of Early Hominid and the Related Environmental Background--the largest ever domestic archaeological research project headed by famous paleontologist Prof. Qiu Zhanxiang--was initiated. This program is aimed at finding primitive human fossils and human traces of living over 2-4 million years ago in the vast areas east of the Qinghai-Tibet Plateau, including the Yunnan-Guizhou Plateau and the east Yangtze River valley, so as to provide evidence for the recent paleoanthropological supposition that the human species might also have evolved in East Asia, especially in the east of China's Qinghai-Tibet Plateau, thus finally solving the mystery of human evolution.

The team led by Dr Jin Changzhu from the Institute of Vertebrate Paleontology and Paleoanthropology under the Chinese Academy of Sciences (CAS) took the lead in making breakthroughs.

Remarkable Discoveries

During the early 1990s, archaeologists unearthed a large number of fossils of mammals dating back 3-6 million years in the Huainan area, Anhui Province. During the excavation which began in April 1998, Dr Jin's team again found a large number of well-preserved animal fossils from that period.

"This area is very promising in containing ancient human fossils, 3-6 million years old, when human evolution was just at its dawn,'' said Jin Changzhu, who graduated from the Changchun Geological Institute in 1976 and later gained a Ph.D at Osaka City University in Japan. With rich archaeological experience, Jin's instincts told him that the excavation should be focused on the south of the Yangtze River because the warmer and more humid climate there was more favorable for the birth of the human race. He then resolutely led his team into the Lailishan Mountain in Suncun Town of Fanchang County, Anhui. The ensuing results prove Jin's was a historic decision leading to finds that would shake the foundations of the world's authoritative theories.

Jin and his colleagues soon discovered an important fractured deposit from the Early Pleistocene in the Lailishan Mountain. They named it "Renzidong''. After 25 days of trial excavation and sorting, they found some fossilized upper and lower jawbones and teeth of Procynocephalus--higher primate species, more than 50 kinds of vertebrate fossils, and some stones which were believed, after preliminary examination, to bear marks of manual work of early hominid. Through research, the team estimated the geological age of this area to be about Early Pleistocene, exactly what they wanted to find.

Large-scale excavation began in September 1998, during which dozens of stone and 10-odd bone artifacts, both bearing apparent marks of manual work, were unearthed from the 32-meter deposit of Renzidong. Some authoritative archaeologists, including Prof. Zhang Senshui and Huang Weiwen, Paleolithic experts, personally went to the excavation site and conducted detailed identification. They corroborated that these artifacts were cultural remains of early hominid.

Shortly after, an international academic symposium was held in Beijing to celebrate the 90th birthday of the famous Chinese archaeologist Jia Lanpo. At the conference, some domestic experts and their counterparts from Japan, the Republic of Korea and Taiwan carefully studied these stone and bone artifacts and agreed that they must be related to human activities.

Along with these stone and bone artifacts, some 100 fossil specimens of 60 varieties were also unearthed. Vertebrate fossils found at Renzidong are rich in variety, with the primitive species of mammals making up a larger component, all extinct long ago.

They include Sinomastodon, Homotherium, Equus sanmensis, Tapirus Hypolagus, Brachyrhinomys and Mimomys. Most of them are common finds in the Late Pliocene-Early Pleistocene strata, and they all became extinct in the Early Pleistocene. According to Jin, the discovery of Equus sanmensis indicates that these animals lived in a period no earlier dating back 2.5 million years.

"Further determination can be made only after comparing them with the results of the Wushan Man studies,'' said Jin.

During the past decade or so, various dating techniques have corroborated that the primitive human and vertebrate fossils unearthed at Longgupo of Miaoyu Town in Wushan County, Chongqing Municipality, located in the Three Gorges area of the Yangtze River, are as old as 2-2.04 million years. Therefore, the Wushan Man is determined to be the earliest Homo (H.) habilis so far found in Asia.

The species of animals found in Renzidong are similar to those at Longgupo, with 15 being identical. However, the former has a higher extinct rate than the latter. Thus, the geological era the former lived in could be traced back to about 2-2.4 million years, Jin said.

"Based on this, we began thinking about those stone and bone tools found in the 2-2.4-million-year-old stratigraphic interval. Who made them, and who used them?''

To answer this question, Jin and his colleagues went to Fanchang's Renzidong again last May and made a more meticulous excavation. Digs produced more stone and bone artifacts with apparent manual chipping marks. This made Jin more confident that 2-2.4 million years ago, prior to the appearance of the Wushan Man, early hominid already lived and bred in the middle and lower reaches of the Yangtze River.

At present, sorting, identification and research work is being undertaken in Beijing with various specimens brought back from Fanchang, and Jin's team also plans to further verify the date of the geological layer of Renzidong through palaeomagnetic dating and ESR (electron spin resonance).

Doubt and Challenge

An idea commonly acknowledged by the paleoanthropological community believes that the Lamapithecus are the earliest ancestors of man, and their physical forms constitute the direct ancestral features of the human species. Some 4-5 million years ago, Lamapithecus evolved into Australopithecus. Being able to walk upright on foot and beginning to use natural tools, Australopithecus is regarded as the earliest form of man, and is followed by H. habilis with a bigger brain, although smaller than that of H. erectus. H. habilis, who began making stone tools, is followed by H. erectus and then H. sapiens. H. erectus learned to use fire, while the physical features of H. sapiens were more similar to those of modern man. With a brain volume considerably bigger than that of H.erectus, H. sapiens finally evolved into the human beings of today. H. habilis lived about 2-4 million years ago.

Past archaeological records showed complete fossil series, consisting of Australopithecus, H. habilis, H. erectus and H. sapiens, and 2-million-year-old stone tools, had been unearthed only on the African continent. Therefore, the archaeological circles commonly believed that man evolved in Africa. However, fossils of H. erectus have been found on every continent, especially in Asia. Scholars then inferred that some 1.6 million years ago, H. erectus began migrating from Africa to Asia, Europe and other continents.

During the 1980s when the hypothesis of man evolving in Africa prevailed, Chinese scientists found respectively in Lufeng and Yuanmou of Yunnan Province, Lufengpithecus (belonging to Lamapithecus) dating back 8 million years and Yuanmouensis (4 million years). They also unearthed fossils of Yuanmou Man or H. erectus Yuanmouensis (late H. habilis, or early H. erectus believed by some others) dating back 1.7 million years. The lack of fossils 2-4 million years ago obviously offered support to the traditional theory of human evolution.

This gap, however, has been filled in the 1990s when the date of the Wushan Man fossils and stone artifacts was finally determined. In addition, a large number of fossils of H. erectus, most dating back no more than 1 million years, were unearthed at the middle and lower reaches of the Yangtze River in the east of the Qinghai-Tibet Plateau.

In fact, experienced Chinese archaeologists Jia Lanpo and Yang Zhongjian said more than once many years ago that according to China's geological and geographical conditions and ecological environment, this area should have contained abundant primitive human fossils and related cultural remains, and that Asia and China in particular are very possibly the birthplace of early man.

With the growing of rich early human evidences in Asia, many Chinese archaeologists, represented by Wu Xinzhi, research fellow with the Institute of Vertebrate Paleontology and Paleoanthropology, commonly believe that it is possible to find human fossils in the same stratigraphic interval containing anthropoid fossils, because the living environment suitable for anthropoids was also suitable for humans.

Scientists unanimously hold the view that the formation of the Great Rift Valley in East Africa is a factor promoting the evolution from ape to man. Then, did the rising of the Qinghai-Tibet Plateau also offer such an opportunity? Moreover, the formation of the Great Rift Valley and the rising of the Qinghai-Tibet Plateau both occurred during the late Cenozoic period. This provides evidence for Chinese scientists to believe that the movement of the latter made the tropical jungles in the middle and lower reaches of the Yangtze River in the east Qinghai-Tibet Plateau (today's Yunnan, Guizhou and Sichuan) turn into subtropical open forest and grassland, an alteration forcing anthropoids to change their methods of moving and physical structure and gradually evolve into H. habilis, H. erectus, H. sapiens and modern man.

Following the discovery of the Wushan Man site, the finding of the Early Pleistocene ruins in Fanchang has greatly encouraged Chinese scientists.

Jin's analysis shows that Fanchang lies on the lower reaches of the Yangtze River. Its natural geographical location is within the northern subtropical sphere. Judging from the nature of primitive animal group composition and ecological circumstances, this area had an environment of forest and grassland in the Pliocene. Along with the climatic changes, especially the influence of the Quaternary Glacier, the forest gradually disappeared, and grassland rapidly expanded. This geographical environment created favorable living conditions for the early human species.

Jin said that the discovery of the stone tools and bones with apparent cut marks from Renzidong indicates that the area is one of the sites with the earliest human traces of living so far found in Asia. The find demonstrates that the period of primitive hominid living in the middle and lower reaches of the Yangtze River is much earlier than original records. This is of great significance in the seeking of clues of early human traces in Asia so as to reveal the mystery of Asian human evolution.

Dr Jin held that the finding of a large amount of ancient stone tools in Fanchang itself has proved the great significance of the existence of the Wushan Man. At the same time, it once again indicates that more than 2 million years ago, early H. habilis who could use stone tools began living in the Yangtze River basin. It also reminds the archaeological circles that a new approach should be applied while probing into the mystery of human evolution.

If the east Qinghai-Tibet Plateau is proved to be the birthplace of human species, there would be two possibilities. One will prove that human evolution is diversified. On the one hand, human beings in Asia might have come from Africa more than 1.6 million years ago. On the other hand, it is much more likely that there was a branch of human species that independently evolved from ape to man in China in remote antiquity.

The other possibility is that Asia might be the birthplace of the human race, instead of Africa.

"No matter what the outcome, the achievements of Chinese scientists over the past decade or so have posed a strong challenge to the hypothesis of man evolving in Africa that has long dominated the paleoanthropological world,'' Jin said.

Currently, scientists involved in the Study of Evolution of Early Hominid and the Related Environmental Background are still making explorations in Yunnan's Yuanmou, Three Gorges area of the Yangtze River and Nihewan area in north China (located in Yangyuan County, Hebei Province, where a large number of stone artifacts dating back more than 1 million years have been unearthed in recent years).

Jin estimated that the excavation work will last for at least six to seven years in Fanchang. "More encouraging results will be achieved in the end,'' said Jin.