Migration and adaptation of Jomon people during Pleistocene/Holocene transition period in Hokkaido, Japan

摘要

This study examined temporal changes in the archaeological records of the Pleistocene/Holocene transition in Hokkaido, northern Japan, based on assemblage composition, radiocarbon ages, projectile point flaking pattern, and site distribution, with a particular focus on the lithic reduction technique. It explained the formation processes of Jomon society in response to climate change as follows. In Hokkaido, pottery emerged during the Late Glacial (LG) warm period (ca. 15,000-13,000 cal BP) because the Incipient Jomon people migrated from Honshu to the north. The Incipient Jomon communities coexisted with the Terminal Upper Paleolithic (TUP) people that had continued to occupy the region since the stage prior to the LG warm period, but the Incipient Jomon population was relatively small. During the LG cold period (ca. 13,000-11,500 cal BP), the subsistence and settlement strategies adopted by the Incipient Jomon people could not continue in Hokkaido. There is currently no reliable evidence of human activity during the LG cold period. Nevertheless, the analysis of stone tool-making patterns has revealed that stone tool making originating among the TUP people is found in an early Initial Jomon assemblage from the Taisho 6 site. It has an accepted date range of 11,000-10,000 cal BP. This indicates that TUP people's more mobile lifestyle might have enabled them to adapt to the LG cold environment. In the initial Holocene, there was a change in subsistence strategy evidenced in the increase in pottery vessels and the emergence of tools for processing of plant foods. The dramatic warming at the beginning of the Holocene is thought to have significantly changed the TUP people's subsistence strategies and lifestyles.