**4. Discussion: lithic technology and human behavior**

Lithic technology, as defined by Odell (2001), incorporates the various processes that lead to the production of stone tools, including strategies of modification and reduction sequence, knapping equipment, as well as knowledge of raw materials and operative forces [17]. In this regard, lithic technology is an important method to understand the behavior of prehistoric humankind, their societies and history [18]. For the lithic technology during the Early to Middle Paleolithic sites here, we can assume they are products of early to archaic *Homo* species such as *Homo erectus*, while the lithic materials from Upper Paleolitihic sites (Hexidong Cave and some cave sites in Tonglu), they can be recognized as products by *Homo sapiens*.

However, with the limit of direct C14 dating of each site, it is yet hard to discuss the change and develop of lithic technology during the Pleistocene from the view of human evolution and behavior here. Thus we focus on lithic technology and human behavior in general by applying the concept of *Chaîne Opératoire*. This concept was developed to attempt describing and understanding the processes of culture transformation [19], so that it emphasis on the dynamics [20]. The analysis based on the concept of *Chaîne Opératoire* should consider the lithic artifacts as a life-cycle human being, and all of stages from raw material procurement to tool modification, utilization, maintenance, and finally discarding should be included [21].
