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In the densely populated region of East Asia, it is important to know the mechanism, scale, and frequency of heavy precipitation brought about during the monsoons and typhoons. However, observational data, which cover only several decades, are insufficient to examine the long-term trend of extreme precipitation and its background mechanism. In humid areas, the transport flux of a suspended detrital material through a river system is known to have an empirical power relationship with precipitation. Thus, the sedimentation flux of a fine detrital material could potentially be used as a proxy for reconstructing past heavy precipitation events. To test the idea that the sedimentation flux of detrital materials records past heavy precipitation events (e.g., typhoons), we focused on the detrital flux estimated from the annually laminated sediment of Lake Suigetsu, central Japan, which is capable of accurately correlating the age of detrital flux with the precipitation record. We first established a precise age model (error within ±1 year in average) beginning in 1920 A.D. on the basis of varve counting fine-tuned by correlation between event layers with historical floods. The flux of the detrital material (g/cm 2 /year) was estimated on the basis of Al 2 O 3 content (wt%), dry bulk density (g/cm 3

The radiocarbon (14C) calibration curve so far contains annually resolved data only for a short period of time. With accelerator mass spectrometry (AMS) matching the precision of decay counting, it is now possible to efficiently produce large datasets of annual resolution for calibration purposes using small amounts of wood. The radiocarbon intercomparison on single-year tree-ring samples presented here is the first to investigate specifically possible offsets between AMS laboratories at high precision. The results show that AMS laboratories are capable of measuring samples of Holocene age with an accuracy and precision that is comparable or even goes beyond what is possible with decay counting, even though they require a thousand times less wood. It also shows that not all AMS laboratories always produce results that are consistent with their stated uncertainties. The long-term benefits of studies of this kind are more accurate radiocarbon measurements with, in the future, better quantified uncertainties.

This paper re-examines lithic technological variability of the Early Ahmarian, one of the early Upper Palaeolithic cultural entities in the Levant, which has often been regarded as a precursor of the Protoaurignacian (the early Upper Palaeolithic in Europe) in arguments for the occurrence of a cultural spread in association with the dispersal of Homo sapiens from the Levant to Europe. Using quantitative data on several lithic techno-typological attributes, we demonstrate that there is a significant degree of variability in the Early Ahmarian between the northern and southern Levant, as previously pointed out by several researchers. In addition, we suggest that the technology similar to the southern Early Ahmarian also existed in the northern Levant, i.e., the Ksar Akil Phase 4 group (the KA 4 group), by introducing new Upper Palaeolithic assemblages from Wadi Kharar 16R, inland Syria. We then review currently available stratigraphic records and radiocarbon dates (including a new date from Wadi Kharar 16R), with special attention to their methodological background. As a result, we propose alternative chronological scenarios, including one that postulates that the southern Early Ahmarian and the KA 4 group appeared later than the northern Early Ahmarian with little or no overlap. On the basis of the alternative scenarios of chronological/geographical patterns of the Early Ahmarian variability, we propose four possible relationships between the Protoaurignacian and the Early Ahmarian, including a new scenario that the appearance of the Protoaurignacian preceded those of similar technological entities in the Levant, i.e., the southern Early Ahmarian and the KA 4 group. If the last hypothesis is substantiated, it requires us to reconsider the model of a Levantine origin of the Protoaurignacian and its palaeoanthropological implications.

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The life history of a female individual skeleton (ST61) from the Edo period (AD 1603(AD -1868 was investigated by using multi-tissue and multi-isotope analyses. Her gravestone and historical documents revealed that ST61 was a grandmother of a chief retainer of the Akashi clan who died in 1732 aged 77 years. Radiocarbon and sulfur stable isotope analyses indicated that the contribution of marine foods to the ST61 diet was relatively low (17.2% protein) despite the relatively higher nitrogen isotope ratio of the rib bone collagen. Carbon and nitrogen stable isotope analysis of the serial section of tooth dentin along the growth lines indicated that breast milk was not the major protein source of ST61 after roughly 1-1.5 years of age, although this weaning pattern was not evident from the oxygen stable isotope ratios of her tooth enamel serial sections. The carbon stable isotopes in tooth dentin collagen and tooth enamel apatite suggested that her diet from 0.5 to 5 years of age possibly contained a small proportion of C 4 plants. Stable isotope ratios of the rib bone and the tooth dentin collagen differed, consistent with historical documents describing a residential change at the age of 27. The calibrated radiocarbon ages of the associated rice hull were at least 80-120 years older than the year of death of ST61. Sulfur stable isotope ratio of the rice hull suggested that fish fertilizers might have been used for paddy rice at that time. Multi-tissue and multi-isotope analyses can provide information of several kinds from different time windows even from an individual skeleton.

The oxygen isotopic composition of precipitation is sensitive to the atmospheric dynamics (Dansgaard, 1964;Jouzel et al., 1994). Therefore, the tree-ring cellulose δ 18 O is increasingly used for paleoclimate reconstruction of recent centuries (e.g.,