The shape of technology to come: An examination of evolutionary relationships between bifacial and core technologies at the Lower-Middle Palaeolithic boundary across regions in Eurasia

The origin of Levallois prepared core technology is a subject of debate among Palaeolithic archaeologists. While some argue for a single African origin for this style of core reduction, increasing support is found for a multiple-origin model in which Levallois technology independently evolves out of underlying technology in different regions of Africa and Eurasia. Within a multiple-origin framework, it has been proposed that the technology is realized through the evolution of either Late Lower Palaeolithic core technology or Acheulian bifaces. We explore these hypotheses by examining the relationships between early Levallois technology, proposed transitional types, and Lower Palaeolithic production systems in geographically discrete lithic assemblages in the Armenian Highlands and Britain. The sites of Nor Geghi-1 (Armenia) and Purfleet (Britain) are the focus of this study as they contain evidence for the in situ evolution of Levallois technology. Landmark-based geometric morphometrics is applied to high-quality three-dimensional scans of lithic artifacts from Lower-Middle Palaeolithic sites in the two regions. As this research is focused on morphological characteristics, we also explore factors outside of human decision-making that may affect shape diversity (i.e., raw material, size, reduction intensity). Our results indicate that the appearance of Levallois prepared core technology is likely the outcome of distinctive processes in the two regions. These results further support the growing body of research that argues for a multiple-origin model early prepared core production systems.