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Archaeological investigation of the dentoalveolar complex in situ within a human skull requires detailed measurements using non-invasive techniques. Standard macroscopic and radiographic methods have limitations but large volume micro-computed tomography (LV micro-CT) scanning has the potential to acquire data at high resolution in microns. In this study, archaeological specimens are analyzed using three-dimensional data visualization software from LV micro-CT scans with the aims of (1) determining whether LV micro-CT can act as a single technique to provide detailed analysis of the dentoalveolar complex and (2) how findings from the LV micro-CT technique compare with standard methods. These aims are explored by measuring a range of human skull specimens from a rare archaeological sample requiring non-invasive methods, for multiple dental and alveolar bone health categories. The LV micro-CT technique was the only method to provide a full range of detailed measurements across all categories studied. A combination of macroscopic and radiographic techniques covered a number of categories, but the use of multiple methods was more time consuming, did not provide the same level of accuracy, and did not include all measurements. There were high levels of reproducibility for intra-operator scoring and good inter-operator agreement from four operators with one operator whose results were outliers. As a further investigation of the potential of the LV micro-CT technique, an additional individual, a fragile, fragmented skull of an infant was studied. This investigation confirms the value of LV micro-CT scanning as a non-invasive, accurate, single technique for the extensive analysis of the dentoalveolar complex within archaeological skulls, which also allows the relationship of different tissues to be studied in situ.  相似文献   
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Ancient human migrations provide the critical genetic background to historical and contemporary human demographic patterns. However, our ability to infer past human migration events, especially those that occurred over rapid timescales, is often limited. A key example is the peopling of Polynesia, where the timing is relatively well defined, but the exact routes taken during the final stages and the source populations are not. Here, we discuss the technical limitations of current methods for inferring rapid human migration events, using the final stages of Polynesian migration as an example. We also introduce a promising new proxy method to infer human migrations—patterns of bacterial evolution within ancient dental calculus (calcified plaque). While we focus on Polynesia, this method should be applicable to other past migrations, enhancing our understanding of human prehistory and revealing the crucial events that shaped it.  相似文献   
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A high-resolution chronostratigraphy has been established for an eroding Atlantic round house at Sloc Sàbhaidh (North Uist, Scotland), combining detailed OSL profiling and dating of sediments encompassing the main bracketing events associated with the monument, radiocarbon AMS dates on bone recovered from excavated features and fills within it, and TL dates on pottery and burnt clay. Concordant OSL and radiocarbon evidence place construction of the wheelhouse in the first to second centuries AD, contemporary with dates from the primary occupation. Beneath the wheelhouse, clay deposits containing burnt material, attest to cultural activity in vicinity to the monument in the preceding second to first centuries BC. At a later date, the southern wall collapsed, was rebuilt, and the interior spaces to the monument re-structured. The chronology for the later horizons identified from the sediment luminescence dates extends to the second half of the first millennium AD, which goes beyond the range of the radiocarbon dates obtained. The data from ceramics encompass both periods. The juxtaposition of the dating evidence is discussed relative to short and longer chronologies for this Iron Age monument. Corollaries of this research are the implications that based on the long chronology, some of the ecofacts (bone) appear to be residual, and that the temporal duration of Hebridean Coarse Ware may extend into the second half of the first millennium AD.  相似文献   
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Establishing the construction sequence of agricultural terraces is extremely complicated due to the nature of their technological foundation and use. A number of methodological approaches have been developed to address this difficulty, such as bulk soil 14C dating, Optically-Stimulated Luminescence (OSL), sediment grain size, or a combination of these, but a fundamental problem of stratigraphic disturbance still exists. In this article, we utilize multiple datasets, including radiocarbon determinations, faunal isotopic signatures, human osteological remains, archaeobotanical data sets, energetics assessments, and spatial data to establish the origins of Philippine Cordillera rice terraces. Dominant historical narratives in the region suggest a 2000–3000 b.p. inception of the terrace systems, but previous Bayesian modeling and current archaeobotanical, ethnohistorical, and ethnographic data indicate that the shift to wet-rice cultivation is a recent phenomenon and a response to the intrusion of the Spanish Empire in the northern highland Philippines.  相似文献   
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