A Sino-American scientific team, lead by Dr. GAO Xing, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, carried out a systematic archeological investigation from June to July, 2009 in the Tibetan Plateau Margin Region, and six sites were discovered. A large number of archeological remains such as stone artifacts, broken animal bones, hearths, charcoals have been unearthed, according to a preliminary report published in the latest issue of Acta Anthropologica Sinica 2010 (2).

“The stone artifacts in the Tibetan Plateau Margin Region consisted of cores, flakes, chunks, microblade cores, microblades, and retouched tools”, said YI Mingjie, lead author, a graduate student under the direction of Dr. Gao at IVPP , “As a dominative tool type, some of the scrapers were retouched elaborately. The stone assemblage at this region shows that the flake industry and microblade industry were used synchronously in the majority of the sites.”

Some charcoals collected from the hearths are able to yield radiocarbon dates. The age of Yantaidong (also called “Ten Hearths”) Site is about 10360±60 yr BP, and Baifosi (also called “White Buddha Temple”) Site is dated back to 4280±40 yr BP. According to sites discovered in this region, archeologists suggest that at the last time of human living space’s expansion, Tibetan Plateau got its chance to attract human to move in, mainly due to: 1) the increase of human’s ability to get food, 2) broad spectrum revolution of people’s diet, 3) the progress of tool-making technology, 4) the pressure of natural resources, 5) the warm and wet weather conditions during interglacial stage. With these factors, human caught the opportunity to move into Tibetan Plateau gradually.

During 40-25ka BP, the last interglacial, climate was moist and warm, which provided possibility for human to move in. “Archeological materials showed that the human presence in the region around the time 30kaBP, in the form of seasonally capturing resources. Lenghu locality 1 and Xiao Qaidam Lake are the possible representatives”, said Dr. Gao, team lead and coauthor, “But it still needs a further study on the chronology of these sites.”

The age from 25 ka BP to 18 ka BP was the Last glacial maximum, the cold and dry climate offered a poor living condition, and the condition lasted to 15 ka BP. No human remain in this period has been found yet.

After 15 ka BP, the climate of Tibetan Plateau margin region became suitable for human. A few sites have been found, and some of them, such as Heimahe Site and Yantaidong Site suggest a type of social and foraging organization involving multiple family groups occupying the location for an extended period of time, probably it stands for a systematic seasonal use.

“The discoveries and excavations are important to enriching the information of the culture in Tibetan Plateau Margin Region and helpful to study the early human’s behavior and technology in this region”, said P. Jeffrey, coauthor, Department of Anthropology, University of California Los Angeles.

Fig. 1  Location of excavated sites in 2009 in the Tibetan Plateau margin region (Images by YI Mingjie).

Fig.2  Lithic artifacts discovered from Tibetan Plateau margin region (Images by YI Mingjie).