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Until now, the oldest known human hair was from a 9000-year-old South American mummy. Here we report fossil hairs of probable human origin that exceed that age by about 200,000 years. The hairs have been discovered in a brown hyaena (Parahyaena brunnea) coprolite from Gladysvale cave in South Africa. The coprolite is part of a hyaena latrine preserved in calcified cave sediment dated between 195,000 and 257,000 years ago. This find supports the hypothesis that hyaenas accumulated some of the early hominin remains found in cave sites, and provides a new source of information on Pleistocene mammals in the Sterkfontein Valley.  相似文献   
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Soil multi-element analysis is now a routine technique employed to help answer questions about space use and function in and around archaeological sites. The pattern of enhancement of certain elements, including P, Pb, Ca, Zn, and Cu, has been shown by numerous studies to correlate closely with the archaeological and historical record. Interpretation of these soil signatures, however, has generally been more problematic. One approach to the problem has been the use of ethnographic or “known” sites to guide interpretation, but how confidently can results from one site be extrapolated to another? This study of abandoned farms tests the site specificity of soil multi-element signatures of past space use through the use of discriminant models. Data analysis suggests that one to one comparisons of similar sites are much less accurate (38% accuracy) than comparisons based on a wider range of sites (59.3% accuracy), even when the latter have contrasting geology. The results highlight the importance of individual anthropogenic practices during occupation and abandonment in the development of diagnostic soil geochemical signatures.  相似文献   
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This study uses stable isotope analyses (δ13C and δ15N) of human bone collagen to reconstruct the diet of three Romano-British (first to early fifth century AD) populations from Gloucestershire in South West England. Gloucestershire was an important part of Roman Britain with two major administrative centres at Gloucester (Glevum) and Cirencester (Corinium) and numerous smaller settlements and farmsteads. To investigate potential dietary differences between the rural and urban populations of Roman Gloucestershire, we compared human bone collagen stable isotope values from 32 individuals from urban Gloucester with those of 46 individuals from two rural cemeteries at Horcott Quarry and Cotswold Community, respectively. Seven individuals from urban Gloucester were buried in a mass grave; all others were buried in single inhumations. Results show small but significant differences in stable isotope ratios between the urban and rural populations which indicate that the urban population might have consumed slightly more marine and/or freshwater resources than the people living in the rural communities. We interpret this difference as a direct reflection of Rome’s influence on Gloucester’s population and the town’s economic status. Subtle differences in stable isotope ratios were also observed at the site level, as burial practice does correlate with diet in some cases. Overall, the results from this study demonstrate that diet, as reconstructed through stable isotope analysis, is a very sensitive, if settlement-specific, indicator of social differentiation and culture change.  相似文献   
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A key area in the analysis of urban structural evolution is identifying discontinuities. Effective analysis could improve long‐term forecasting and provide a better understanding of how to steer an urban system toward a desirable future state. We use a simple aggregate retail model to demonstrate an algorithm for identifying discontinuities in model parameter space. Explorations of retailing in both Greater London and South Yorkshire in the United Kingdom illustrate how understanding a system's potential for discontinuity can provide insights for both policy makers and retail businesses. The Harris and Wilson model, described in the section so‐named, is used as a simple archetype to illustrate the new framework. This model can be developed in a straightforward way to incorporate further refinement. In “ Executing the model and visualizing the results ,” we describe a single model run and in “ Investigating discontinuities ,” we explain our framework for detecting and analyzing discontinuities. “ Identifying discontinuities in the London retail system ” shows the results of applying this methodology to the Greater London retail system, and in “ Practical applications ,” we explore the policy applications for this technique as related to the decline of town centers in the South Yorkshire retail system. Some concluding comments are offered in “ Conclusions .”  相似文献   
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Netzwerk DVAG     

DVAG intern

Netzwerk DVAG  相似文献   
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