Spatiotemporal variability in lithic technology of Middle-to-Upper Paleolithic Asia: A new dataset and its statistical analyses

The dispersal processes of anatomically modern humans in Asia during the late Middle to early Upper Paleolithic periods have been a focus of intensive research in recent years through interdisciplinary approaches including genetic, paleoanthropological, and archeological studies. However, sparse datasets, often only available from limited time-space contexts have not produced a satisfactory picture of the vast geographic extension of this continent. This study investigated how the chrono-spatial patterning of lithic technological records, which are widely available across Asia, might contribute to our better understanding of the population dynamics in this period. The study is based on a large database (PaleoAsiaDB) recently developed by the authors to accommodate the relevant datasets, including geographical coordinates of each site and available radiometric dates, for the Middle and Upper Paleolithic periods in Asia. Each of the 895 lithic assemblages was characterized in terms of the presence/absence of 24 lithic modes/submodes that were adapted from the work of John Shea to fit our research objective. The dataset was analyzed using exploratory statistical methods, including principal component analysis. The results revealed marked spatiotemporal patterns in technological variability from the late Middle to early Upper Paleolithic periods. Some can be interpreted as a result of modern human dispersal, whereas others are better explained from ecological and other perspectives rather than authorships. Although this study has obvious limitations due to its reliance on the information sourced from the literature, it provides a global synthesis of lithic variability in the crucial period of the dispersals of modern humans on a continental scale for the first time. The results serve as a guide to be tested with evidence from other research strategies, such as genetics and fossil studies.