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Here we present the stable isotope ratios of carbon and nitrogen measured in bone collagen extracted from humans, dogs, herbivores and fish from Mesolithic and Neolithic coastal and inland sites in Denmark. Bones of freshwater fish from several Early Mesolithic lake-side sites have δ13C values surprisingly similar to those seen in marine fish. We propose a model, based on δ13C and δ15N, for the correction for both marine and hard water reservoir effect in radiocarbon dates. A strong reliance on aquatic protein is demonstrated for the Mesolithic inhabitants of the region from the middle of the Early Mesolithic onwards. A significant part of the protein in the diets of the dogs and humans from the Middle and Late Mesolithic was of marine origin, even at inland sites. This observation points to a high degree of (seasonal) coast-inland mobility. The isotopic evidence indicates that during the Neolithic small quantities of aquatic foods were still common sources of dietary protein.  相似文献   
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Carbon and nitrogen stable isotope values were measured from bone collagen extracted from archaeological Nubian human (n = 54) and faunal (n = 61) populations from the site of Kerma, Sudan. Collagen suitable for isotopic analysis was extracted from 22 faunal and 48 human samples from the Eastern cemetery site, dated to the Middle Kerma (c. 2050–1750 BC) and Classic Kerma (c. 1750–1500 BC) periods respectively. The isotopic data indicate that the human dietary regimen included a mix of C3 and C4 plant-derived components, with a larger C4 component than previously reported in archaeological Egyptian Nile Valley populations. Elevated δ15N values are attributed to consumption of dietary resources from a 15N-enriched terrestrial ecosystem. The faunal isotope data also indicate the consumption of C3 and C4 plants. The large range of δ13C values measured in both the human and faunal samples supports previous work suggesting that a significant portion of the populations buried at Kerma may have originated elsewhere, further confirming the Nile Valley as a major corridor for population movement in the region.  相似文献   
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Here we report δ13C and δ15N measurements of serial sections of human deciduous and permanent tooth dentine from archaeological samples taken from the medieval village site of Wharram Percy, Yorkshire, UK. We found a pattern of enrichment, for both δ13C and δ15N, where the tooth crown was greater than the cervical part of the root, which in turn was greater than the apical portion of the root and the associated rib collagen values. This pattern reflects a decrease in the consumption of isotopically enriched breast milk and the introduction of less enriched weaning foods in the diet. The (mean±SD) difference between the deciduous second molar crowns and corresponding rib samples from the same individuals after 2 years of age was 1.2±0.4‰ for δ13C and 3.2±0.8‰ for δ15N. The δ15N values are as predicted, but as there were no C4plants at Wharram Percy, this 1.2‰ enrichment in δ13C represents clear evidence of a carbon trophic level effect in collagen from breastfeeding infants. Carbon and nitrogen results also show that the infant diet among those who died in infancy did not differ from those who survived into childhood. This study demonstrates the promise of using dentine serial sections to study the temporal relationships of breastfeeding, weaning, and dietary patterns of single individuals.  相似文献   
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It is now three decades since Waterbolk introduced evaluation criteria to 14C chronology. Despite this, and other subsequent attempts to introduce quality control in the use of 14C data, no systematic procedure has been adopted by the archaeological community. As a result, our databases may be significantly weakened by questionable dates and/or questionable associations between dated samples and the archaeological phenomena they are intended to represent. As the use of chronometric data in general becomes more ambitious, we must pause and assess how reliable these data are. Here, we forward a set of evaluation criteria which take into account archaeological (e.g. associational, stratigraphic) and chronometric (e.g. pre-treatment and measurement) criteria. We intend to use such criteria to evaluate a large 14C dataset we have assembled to investigate Late Glacial settlement in Europe, the Near East and North Africa, supported by the Leverhulme Trust. We suggest that the procedure presented here may at least form the basis of the development of more rigorous, scientific use of 14C dates.  相似文献   
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Many indigenous populations are experiencing rural-to-urban migration. In making this transition, indigenous peoples are entering industrial societies where most income derives from wages or salaries, and formal educational achievement is crucial in determining economic prospects. This research analyzes the gap in test score results between Aboriginal and non-Aboriginal students in public schools in the Canadian province of British Columbia. It finds a strong effect of school quality, as measured by non-Aboriginal achievement, on Aboriginal achievement. It also finds a nonlinear negative relationship between Aboriginal achievement and the number of Aboriginal students in a school over the empirically observed range. It thus suggests a possible trade-off and dilemma between, on the one hand, policies that enable Aboriginal students to concentrate in a few schools able to provide a culturally sensitive curriculum and, on the other, policies to maximize Aboriginal academic achievement.  相似文献   
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Archaeological fish bones reveal increases in marine fish utilisation in Northern and Western Europe beginning in the 10th and 11th centuries AD. We use stable isotope signatures from 300 archaeological cod (Gadus morhua) bones to determine whether this sea fishing revolution resulted from increased local fishing or the introduction of preserved fish transported from distant waters such as Arctic Norway, Iceland and/or the Northern Isles of Scotland (Orkney and Shetland). Results from 12 settlements in England and Flanders (Belgium) indicate that catches were initially local. Between the 9th and 12th centuries most bones represented fish from the southern North Sea. Conversely, by the 13th to 14th centuries demand was increasingly met through long distance transport – signalling the onset of the globalisation of commercial fisheries and suggesting that cities such as London quickly outgrew the capacity of local fish supplies.  相似文献   
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This paper presents 19 AMS radiocarbon dates from nine pre-Hispanic Caribbean (Taíno/Lucayan) wooden sculptures in the British Museum collections, provenanced to Jamaica, Hispaniola and the Bahamas. Together with strontium isotope results and wood and resin identifications, these data build a material and chronological context for some of the most recognised examples of Taíno art – from duhos (ceremonial seats) and cemís (free standing depictions of deities, ancestors and spirits) to canopied stands used to hold hallucinogenic drugs during the cohoba ceremony. Each sculpture widens our understanding of Caribbean carving traditions, stylistic variation, chronologies and material resource utilisation. A group of three sculptures recovered from Carpenters Mountains, Jamaica, carved by AD 1300 and brought together as a ceremonial ‘set’, each appear to have had their inlays renewed over a century later, suggesting long-term use. Three key examples of the main Caribbean duho categories (high-back, low-back and extended), provide insights into the diversity of styles present in the region post-AD 1100. The British Museum's corpus enables an exploration of regional styles, and potentially the work of individual artists.  相似文献   
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