The Initial Upper Paleolithic in Central and East Asia: Blade Technology, Cultural Transmission, and Implications for Human Dispersals

Archaeological assemblages labeled as Initial Upper Paleolithic are often seen as possible evidence for dispersals of Homo sapiens populations in Eurasia, ca. 45,000 years ago. While most authors agree that the IUP can be recognized by a set of shared features, there is far less consensus on what these features are, and what they mean. Because of methodological challenges inherent to long distance comparisons, documenting and establishing a firm connection between archaeological assemblages remain difficult and often draw legitimate skepticism. There could be many reasons why Paleolithic hunter-gatherers used comparable technologies, but it usually comes down to two kinds of processes: cultural transmission or convergence. In other words, technological similarities may illustrate a cultural link between regions or may be caused by mechanisms of independent reinvention between more distantly related populations. Here, I focus on three assemblages from the Siberian Altai, Zabaikal region, and North Mongolia to address one main question: is there such thing as a united IUP in Central and East Asia, or are we looking at unrelated yet comparable adaptive processes? First, I describe the common structure of lithic blade production at the sites, with special attention to derived features relative to the regional sequence. After comparing the complexity of the production system with those of other lithic technologies, I suggest that this coherent, intricate, yet unprecedented technological pattern found across contiguous regions in Asia is better explained by transmission processes than by multiple unrelated reinventions, or local developments. The blade production system described in Siberia and Mongolia reoccur as a package, which is consistent with indirect bias and/or conformist cultural transmission processes. Overall, the results point toward close contact between individuals and hunter gatherer populations, and supports the recognition of a broad cultural unit to encapsulate Asian IUP assemblages. Considering other lines of evidence, the geographical and chronological distribution of Asian IUP lithic technology is consistent with a dispersal of Homo sapiens populations in Central and East Asia during the Marine Isotopic Stage 3, although the geographical origin of such movement is less clear.