Ecological niche modelling (ENM) is a computer-based method to extrapolate the niche probability of a species through machine learning using (1) known location of a species’ occurrence and (2) environmental factors such as temperature, precipitation and elevation. ENM is applicable to prehistoric archaeology based on the assumption that human behaviour and niche constructions were largely constrained by environmental factors. This paper applies ENM to a large-scale data of Upper Palaeolithic (UP) occupations in the Kanto-Koshinetsu region of eastern Japan in order to quantitatively assess and visualise ecological niche of UP populations to understand their behavioural strategies. Spatial niche probability was calculated with reconstructed palaeoclimatic data and landform indices for the Last Glacial Maximum (21ka), taking into consideration four major lithic groups (trapezoids, kakusuijo-sekki, backed blades and microliths), which may reflect different strategies in resource procurement. Results indicated that niche probability was generally high in Musashino, Sagamino and Shimousa uplands in the southern Kanto region, although the observed site distribution was probably biased by intensive rescue excavations due to urban developments. The distance to the obsidian outcrops in the central highland remarkably contributed to the model. A closer look revealed two patches of high niche probability area in the Hakone mountains for the kakusuijo-sekki, backed blades and microliths. These patches were probably parts of a ‘niche corridor’ in association with the transportation of obsidian raw materials between the central highland and Hakone area via the Fujikawa valley.

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The distribution of obsidian sources in the Central Highlands, Nagano Prefecture, shows a dense concentration in a mountainous area between ca. 1,200-2,000m a.s.l.. Upper Paleolithic hunter-gatherers intensively exploited good-quality obsidian nodules from the area for lithic tool production. Obsidian lithic assemblages derived from the Central Highlands are widely distributed over the entire Chubu-Kanto region. The present paper examines the historical changes in land-use with respect to obsidian procurement in the Central Highlands using a comparative analysis between three different types of chronology during the marine isotope stage 3-2 （MIS 3-2） : 1) the sequence of Upper Palaeolithic site distribution patterns in the Central Highlands, 2) changes in obsidian use according to the source areas based on the provenance analysis of Upper Palaeolithic obsidian assemblages from the Chubu-Kanto region, and 3) plaeoclimatic and palaeovegetational changes during MIS 3-2 in the Central Highlands. From the results of the comparative analysis, it is highly likely that multiple factors, such as the concealment of the earlier (pre-MIS 2) site distribution caused by periglacial processes, environmental deterioration during the Last Glacial Maximum, and marked changes in procurement activities for obsidian, had significant impact on the changes in Upper Palaeolithic land-use in the Central Highlands.

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During the end of the Pleistocene (ca. 16,000 to 11,500calBP), bifacial hunting weaponry (e.g., bifacial projectile points and stemmed points) was widely distributed in the northern circum-Pacific region. In the Japanese islands, lithic assemblages assigned to the same period were also characterized by lithic assemblages associated with various bifacial hunting weaponry including large and wide-shaped points, narrow-shaped points, stemmed points, and triangular arrowheads. Although many researchers have focused on the lithic typology, the manufacturing technology, and the chronological sequence concerning those bifacial hunting weapons, the detail of how they were used remains unclear.
In order to examine the human adaptation to palaeoenvironmental changes in the terminal Pleistocene in the largest Japanese island of Honshu, this paper analyzes the breakage pat-terns, particularly focusing on impact breakage (impact fracture) and morphological variations of those points from central Honshu, and discusses a transition in the relations between the type of hunting weaponry and the hunting method. A macrofracture analysis is the most practical and effective method for evaluating human hunting behavior from the stone tool analysis. The analysis confirmed that several bifacial hunting weapons dealt with in this study clearly show the fractures including impact fractures.
A comparative analysis between breakage patterns and morphological features demonstrated that the wide-shaped points were used as thrusting spears (or in another way) and darts ; the narrow shaped points as darts ; and the stemmed points as arrowheads. Additionally, the relation between the morphological variations and the convincing evidence for reshaping of the stone tools indicated that the narrow-shaped points were frequently maintained during hunting activities. These findings suggest that bifacial points were frequently used in hunting weaponry. Accordingly, the way of using bifacial hunting weaponry changed from thrusting spears and darts to arrowheads during the terminal Pleistocene in central Honshu. It is likely that the substantial changes in use of bifacial hunting weaponry and hunting activities are tightly correlated with paleoenvironmetal changes.

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Although recent chronological studies of the Palaeolithic and Incipient Jomon period have strikingly progressed on the basis of radiocarbon dating and tephrochronology, the settlement patterns of prehistoric hunter-gatherers are still not well explored. This paper first takes a retrospective view of the theory of settlement pattern study including optimal foraging theory developed in American archaeology, and, next, discusses diachronic change and inter-regional differences in settlement patterns in the Kyushu region during the terminal Pleistocene, through the analysis of tool kit diversity, tool category diversity, lithic raw material distribution, and composition of archaeological features.
As the result, hunter-gatherers just before the Late Glacial were thought to be highly mobile and to place much importance on hunting activity. During this stage, the mobility magnitude of North Kyushu hunter-gatherers was higher than that of South Kyushu hunter-gatherers. Also, after the onset of the Late Glacial warm period, North Kyushu hunter-gatherers continued a similar settlement pattern and mobility strategy, while South Kyushu hunter-gatherers suddenly started using various lithic tools and lithic technologies, expanded their diet breadth, constructed different archaeological features, and switched to a sedentary way of life. The environmental change and increase of population density caused by Late Glacial climate change might have been major contributing factors to this change.

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We conducted radiocarbon dating of terrestrial and marine remains from the Akamido archaeo-logical site and Choshichiyachi shell midden to evaluate the marine reservoir effect during the initial Jomon period in the inner Hachinohe Bay and to reconstruct the chronology of these sites. The results of radiocarbon dating showed that these shell middens at Akamido pottery type were formed at ca. 8,150-8,000calBP. The ΔR values were estimated at 243±51 to -167±62 ¹⁴C years, and showed clear differences based on the habitat of the marine samples. These data indicated that we should apply the mean ΔR values classified by habitat between marine samples.

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The status of domesticated plants in the Jomon period has started to be argued specifically with the recent development of archaeobotany. This review reveals the existence and the composition of domesticated plants such as the perilla, Glycine, and Vigna Ceratotropis in the central highlands of Japan in this period, according to the plant impressions based on replica-SEM analysis. This paper points out that the cultivation of these herbaceous plants and the management of woody plants such as Castanea occurred and progressed during the process of vegetation change and resource management in secondary vegetation around human settlements.

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Archaeology is a promising research field for the examination of the causes, conditions, and consequences of long-term culture change. This paper discusses the mechanisms of long-term change in ecosystems and subsistence-settlement systems (economic and social systems) from the perspective of historical ecology and resilience theory. The paper starts with a hypothesis that a highly specialized subsistence strategy can support a larger community for a short period, but a decrease in subsistence and food diversity makes the subsistence systems and their associated community more vulnerable in the long run. Under this hypothesis, climate change can be a trigger, but not necessarily the main cause, for a major change in socioeconomic systems. Archaeological data from the Early to Middle Jomon periods of northeastern Japan, particularly lithic assemblage and floral data from the Sannai Maruyama site in Aomori Prefecture, are examined to test this hypothesis. Assuming that lithic assemblage diversity reflects food and subsistence diversity, the results are consistent with the hypothesis. The approach adopted here can be beneficial for developing a new, interdisciplinary discussion on human-environmental interaction and the importance of maintaining food/subsistence diversity as well as biodiversity. Further study is necessary to examine the importance of other natural and cultural factors, such as climate change and incipient social inequality. Refinements of the chronological scale on the basis of AMS ¹⁴C dates are also needed.

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This paper discusses the cultural landscape during the Yayoi Age, reconstructed through a review of geomorphological and vegetational changes at the Aoya-Kamijichi site located in Aoya plain, Tottori Prefecture. The landforms for the settlement of Yayoi people was formed through the accumulation of bed load caused by the regression, around 4,400 to 3,600yrsBP. The pollen analysis indicated that the Cryptomeria japonica (Japanese cedar) forest rapidly expanded in the lowland along with the aforementioned geomorphological change. Given that numerous wooden artifacts excavated from this site are made of Japanese cedar wood, it seems that C. japonica was an important resource for the Yayoi people. During the Late Yayoi Age, rice cultivation had probably spread to a relatively wide area of the Aoya plain. Consequently, the grassland area including paddy fields had increased during this Age. In contrast, it seems that the forest, area including the C. japonica forest and Aesculus turbinata forest, had diminished.

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Main factors for the formation of “Kurobokudo” layer (black humic volcanic ash soil) are as follows. (1) Tephra material : Its weathering products combine easily with humus. (2) Humid and warm or cool climate : The black humic layer could not be formed throughout the volcanic ash soil in northern Japan under the cold climate conditions during the Last Glacial. (3) Grassland vegetation : The black humic layer is formed under grassland vegetation whereas the brown humic layer is formed under climax forest.
We could find two epochs for the development of the Kurobokudo layers in Japan since the Last Glacial. The first epoch (ca. 40ka) is in the late marine isotope stage (MIS) 3, accompanied by the sudden increase in palaeolithic remains. The second epoch (ca. 10ka) corresponds to the beginning of the Jomon period in the MIS 1, when rapid change to the humid and warm climate encouraged human activities. Thus, it seems that the Kurobokudo layers have developed under semi-grassland vegetation resulting from human activities such as the burning and deforestation in man-made ecosystems since the prehistoric period.

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