15 years ago : the discovery of outstanding, yet deformed, fossils
Back in the 1970’s, accidental palaeontological discoveries were reported to the local scientific authorities and several survey, test pits, and excavation campaigns were carried out in the site of Quyuanhekou near the city of Yunxian. In may 1989, an almost complete skull, Yunxian I, was unearthed and, the following year, another one, Yunxian II, was discovered nearby. The site is located 100 m north from the river Han, 1 km west from its merging with the river Quyuan. It stretches out on the fourth terrace, 50 m high and 219 m in true altitude, on the top of a promontory.
The stratigraphy, about ten-meter high, consists of successive layers of sands, gravels and silts resting on a precambrian schist base. The skulls were discovered in Layer 3, associated with abundant lithic and bone material.
Nearly 500 stone tools were unearthed, among which numerous flakes and pebble tools as well as some rare bifaces. Yet the latter were among the first of their kind to be discovered in this part of the world where they were thought not to exist.
Dating this level still remains a debated issue but recent researches tend to give an age of around one million years. The Yunxian fossils, that could belong to the Homo erectus group sensus largo, are thus the oldest currently known in continental Asia. However, these specimens were heavily altered in the course of the fossilization process. The Yunxian I skull was extremely flattened and therefore hardly usable for further palaeo-anthropological analysis. That of Yunxian II was less deformed, an was particularly complete (only its zygomatic bones were missing).
From 2002 to 2004 : scanning, 3D imaging and reconstructing Yunxian II
2D scan and 3D reconstruction
On Henry de Lumley’s impulse and in close collaboration with Chinese scientists from the Hubei province, the project to reconstruct Yunxian II was carried out. Using the successful technologies recently implemented en palaeoanthropology, the damages (deformed, broken and missing parts) were corrected via a completely virtual phase. The purpose was to gather a maximum of information about the story of alterations of Yunxian II in order to reproduce, anti-clockwise, the series of events undergone by this fossil. A three-step procedure was established. Firstly, the hypothesis of reconstitution was discussed on the basis of the data collected from different sources (macroscopic external examination, numerical internal data). Eventually, the reconstruction was achieved, by computer, through 3D imaging. Finally, the reconstructed specimen was produced as a prototype.
From then, this fossil became more usable for an anthropological study. The endocranial capacity appeared to be lower (around 1050 cm3) than what was previously calculated on the basis of the deformed fossil’s external measurements (1220 cm3). The face, more complete, could be compared to that of other fossil and modern hominids. As a result, the layout of Yunxian II facial bones appears to be very similar to that of modern man, thus drawing an ancestral line between “him” and us.
The authors of the reconstruction : Li Tianyuan and Amélie Vialet
This achievement became the subject of numerous lectures in France and abroad and was published in international journals . Finally, the reconstructed Yunxian II skull was first presented to a wider public at the Musée de l’Homme in Paris during the « The First Men in China » exhibition (March, 31st 2004-January, 3rd 2005) and finally offered to our Chinese partners during the last International Anthropology Symposium in presence Mr the French Ambassador in China (October 18th-22nd 2004).
The reconstructed Yunxian II skull handed-in by Mr the French Ambassador in China to the members of the Peking Academy of Sciences
for a pdf version of the article : firstname.lastname@example.org
 A. Vialet et al. (2005) Proposition de reconstitution du deuxième crâne d’Homo erectus de Yunxian (Chine). CR Palevol 4 : 265-274