The relationship between microblade morphology and production technology in Alaska from the perspective of the Swan Point site

Microblades are one of the stone tools that spread toward the northeast with wide range human migration after the Last Glacial Maximum in Beringia, and are key to understanding the first migrants to the New World. The Yubetsu method was one of the most widely spread techniques in western Beringia. In Eastern Beringia, Swan Point is the only archaeological site bearing microcores from the East Beringian tradition phase I (here after EBt-I) layer which were produced by the Yubetsu method. There are three archaeological complexes in interior Alaska following EBt-I: the Nenana, Chindadn, and Denali. The former two complexes bear distinctive Chindadn points and the latter has Campus type microcores. Cultural continuity of the local complexes has been argued for decades in discussing the peopling of the Americas. However, because the distinctive Yubetsu microcore is only found at the Swan Point site, discussing cultural connection among these complexes based on microcores is difficult. The Chindadn point was also considered to have roots in the Old World, but no candidate yet has been confirmed. In contrast, large numbers of microblades have been found in EBt-I, Chindadn and Denali complexes, and also in the Northern Archaic tradition, although their production methods are different. In this study we use microblades from EBt-I and Northern Archaic tradition components at Swan Point to elucidate co-occurrence of microcore technological and microblade morphological changes. Results from this study show continuous production of microblades for slotted osseous point weaponry was stable through time. Given that cultural change occurred, the results provide a framework to discuss the continuity of hunting weapon technology and its relationship with hunting prey, indirectly, and with zooarchaeological studies.