Masami Izuho

Toward an Understanding of Technological Variability in Microblade Assemblages in Hokkaido, Japan

Five decades of research history on the late Upper Paleolithic in Hokkaido (northern Japan) shows that microblade assemblages appeared by approximately 20,000 B.P. and that various microblade technologies were developed during late Pleistocene. The empirically observed good association between the morphological features of lithic raw materials and the reduction sequences of microblade cores demonstrates that morphological features of procured lithic raw materials (i.e., size and surface condition), which were constrained by unique geological and geoarchaeological characteristics in Hokkaido, created remarkable variability in reduction methods of microblade technology. This implies that geoarchaeological perspective can contribute to understanding technological variability in microblade assemblages in northeastern Asia.

Lithics and climate: technological responses to landscape change in Upper Palaeolithic northern Japan

Abstract Studies of human behavioural responses to climate change have begun to address traditional archaeological questions in new ways. Hitherto, most of these studies have focused on western Eurasia, but the question of human response to rapid climatic changes in northern Japan during the Upper Palaeolithic period opens up new perspectives. Combining artefact studies and palaeoenvironmental evidence, Japan provides a case study for how quickly modern humans adapted to new environmental challenges, and how that adaptation can be charted through the lithic technologies employed in different geoclimatic circumstances.

Last Glacial Maximum Human Occupation of the Transbaikal, Siberia

Abstract We analyze the late Pleistocene radiocarbon chronology of the Transbaikal region of Siberia and conclude that humans inhabited the area during parts of the Last Glacial Maximum, but completely abandoned it between 24,800 and 22,800 cal yr BP. Moreover, the distinct contrast between non-microblade producing sites and those with microblades on either side of the radiocarbon gap suggests that the new technology arrived with recolonization.

Human Adaptive Responses to Environmental Change During the Pleistocene-Holocene Transition in the Japanese Archipelago

It is well known that environmental conditions from the Late Pleniglacial to the Preboreal fluctuated abruptly. To explain lithic technological and human behavioral change for this period, the influence of environmental changes driven by climatic fluctuation should be addressed. This paper discusses human adaptive responses to environmental change during the Pleistocene-Holocene transition (19,000 ~ 10,000 cal BP) in the Japanese archipelago, compiling radiocarbon ages that have recently accumulated throughout this archipelago and analyzing diachronic and interregional variability of lithic technology, its organizational characteristics, and its role in reflecting human responses to environmental change. Through these analyses, we consider human behavioral variation within the context of paleoenvironmental changes during this transitional period.

New AMS Dates from the Shukubai-Kaso Site (Loc. Sankakuyama), Hokkaido (Japan): Refining the Chronology of Small Flake-Based Assemblages during the Early Upper Paleolithic in the Paleo-Sakhalin-Hokkaido-Kuril Peninsula

ABSTRACT This paper reports accelerator radiocarbon dates obtained from 14 charcoal specimens recovered from the Shukubai-Kaso site (Loc. Sankakuyama), which was excavated in 1973. The small flake-based assemblage from the site has been chronologically attributed to represent the oldest archaeological occupation in Hokkaido. Because the new radiocarbon dates, stratigraphic sequences, and site context do not contradict each other, we conclude that the ages of the archaeological components in Layer III of Shukubai-Kaso (Loc. Sankakuyama) fall within the interval of 29,530 and 28,480 cal yr BP. These ages are close to previously estimated dates for other small flake-based assemblages including the Wakabanomori, Kamiitaira, and Kyu-Shirataki 3 sites. They are also 1500 years older than last glacial maximum (LGM) assemblages on the Paleo-Sakhalin-Hokkaido-Kuril peninsula. These new ages reliably place the small flake-based assemblages in the chronological phase prior to the onset of the LGM.