Holocene climatic fluctuation and lithic technological change in northeastern Hokkaido (Japan)

Abstract In Japan, a body of archaeological assemblages with radiocarbon dates has been providing better understanding of relationship between lithic technology, pottery culture, settlement system, social change, and environment. This paper presented newly conducted radiocarbon dating on charred residue on potteries from Initial Jomon sites in northeastern Hokkaido. This work evidenced current pottery typological chronology and allows us to confirm diachronic lithic technological change associated with these potteries. Regarding the lithic technology, it became clear that lithic technological change into sophisticated blade technology suddenly occurred around 8400 cal BP, then lasted for very short time period until 8000 cal BP in northeastern Hokkaido, and that there was a clear technological gap between this sophisticated blade technology and the previous or subsequent simple flake technology. Since lithic raw material procurement strategy changed during this period, it is supposed that settlement system and foraging strategy might also be reorganized. According to the correspondence between duration of the sophisticated blade technology and global climatic fluctuation, it is likely that 8.2 ka climatic event (maximum duration is roughly 8300–8050 cal BP) was responsible for this sudden change of blade technology. At present, regional environmental change driven by this global climatic fluctuation is not evidenced yet, but there is enough possibility that sudden appearance of sophisticated blade technology might have been caused not only by simple population dynamics or diffusion, but by rapid change in environmental condition.