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91.
Stable isotope analyses have been applied to human and faunal bone collagen from the Varna I and Durankulak cemeteries to explore palaeodietary adaptations in the Neolithic and Eneolithic (Copper Age). The results suggest both populations primarily utilised terrestrial, C3-based diets, despite their proximity to the Black Sea. The wider δ15N range of the Durankulak humans likely indicates the differential utilisation of terrestrial meat sources, which is probably related to the degree to which primary and/or secondary ovicaprid products were consumed, particularly since ovicaprid δ15N values differ from other herbivores. The isotopic distribution of Varna I reflects a linear relationship between δ15N and δ13C, suggesting that a minority of individuals enriched in both isotopic parameters supplemented their diets with marine resources. These burials include the well known ‘chieftain’ (burial 43) and show notable material wealth by way of grave goods. At the population level, however, there is no significant correlation between stable isotope values and material wealth at Varna I, a fact with implications for theories regarding emergent social/economic hierarchies in Balkan prehistory. Five burials at Durankulak were found to have relatively enriched δ13C and δ15N values with respect to the rest of the population. These burials reflect a prominently marine-based or mixed terrestrial C3-based diet that included C4 inputs, possibly from millet, for which the limitations of stable isotope analysis on bulk collagen are not able to differentiate. AMS dating has shown that these burials belong to a much later period.  相似文献   
92.
Little is known about the diversity of volcanic glass sources used in prehistoric northeast China. Although preliminary research established the presence of a number of sources in archaeological sites from this area, the exact location of these sources was not known (Jia et al., 2010). A recent geoarchaeological survey of three source areas and new data derived from portable X-ray Fluorescence elemental analysis (pXRF) has revealed not only the location and use of two new geological sources in northeast China but also extended our understanding of the geologic context of volcanic glass from Tianchi/Paektusan Volcano, the major geological source of volcanic glass in northeast China. Furthermore, understanding the geological history of these new sources clarifies why they were only found in archaeological sites dated to the Holocene.  相似文献   
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This article outlines recent advances in establishing and understanding the prehistoric sequence in mainland Southeast Asia. Research has been unevenly distributed, varying from virtually none in Cambodia to a marked intensity in Hong Kong and the adjoining mainland. A new pattern is becoming apparent, due in no small part to the new findings in southern China. It is argued that despite its long history of occupation, beginning withHomo erectus almost a million years ago, tropical Southeast Asia was occupied by scattered inland groups and larger, possibly sedentary coastal foragers until exposed to intrusive agricultural societies during the third millennium BC. These communities, which originated ultimately in the Yangzi Valley, brought with them rice cultivation and were responsible for the wide distribution of Austroasiatic languages. The three divisions of this language superfamily are now distributed from eastern India to southern China. Following a relatively brief Neolithic period, small and autonomous communities, particularly in Lingnan and Bac Bo (Guangdong and Guangxi provinces of China and the area of the Red River Delta), were exposed to exchange contact with the Shang state of the Chinese Central Plains, and this brought exotic jades and bronzes. Within this context, a local bronze industry was established between 1500 and 1000 BC over much of Southeast Asia, but without any obvious social developments until the middle of the first millennium BC, when several major changes occurred. These incorporated iron smelting and forging and exposure in the southern parts of the region to Indian mercantile contact and along the northern margins to the expanding Chinese empire. Adaptations varied regionally, from the establishment of warrior chiefdoms to counter the Chinese to the construction of water control systems in the arid heart of Southeast Asia to alleviate environmental unpredictability. It is within these regional changes that we can identify trends toward the establishment of states, some of which persisted in an unbroken lineage to the present.  相似文献   
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Palaeoanthropologists and archaeologists have advanced a wide range of explanatory narratives for the various movements of Homo erectus/Homo ergaster, and the first modern Homo sapiens, “Out of Africa”—or even back again. The application of Occam's razor—a parsimonious approach to causes—gives a more cautious approach. There is nothing in the available evidence that would require the ability for a human water crossing from Africa before the later Pleistocene, whether across the Strait of Gibraltar, the Sicilian Channel or the southern Red Sea (Bab el-Mandab). A parsimonious narrative is consistent with movements across the Sinai peninsula. The continuous arid zone from northern Africa to western Asia allowed both occupation and transit during wet phases of the Pleistocene; there is no requirement for a “sponge” model of absorption followed by expulsion of human groups. The Nile Valley as a possible transit route from East Africa has a geological chronology that could fit well much current evidence for the timing of human migration. The limited spatial and temporal opportunities for movements “Out of Africa,” or back again, also puts particular difficulties in the way of the gene flow required for the multiregional hypothesis of the development of modern Homo sapiens.  相似文献   
97.
Parking coupon programs help downtown shopping areas attract consumers away from suburban shopping centers. Here we conduct an empirical analysis of retailer participation in such a program. Consistent with expectations, participation was higher for stores in shopping centers than for street-front retailers, for stores receiving subsidies for coupon purchase, and for stores selling comparison-shopping goods than for stores selling goods bought on one-stop, single-purpose or multipurpose-shopping trips. Participation also varied with numbers of competitors, chain membership, and store vintage. Apparently, participation is a local public good for downtown retailers and stores are inclined to free ride.  相似文献   
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For more than half a century, the Robert E. Lee Camp Soldiers' Home in Richmond, Virginia, provided shelter, food, and medical care to some of the South's neediest Confederate veterans. Applications to the Lee Camp home offer valuable insight into the post-war experiences of a substantial number of Confederate veterans and highlight the enduring effects of the Civil War upon those who fought in it. For such men, the long-term physical and economic ramifications of the conflict largely exceeded the capabilities of existing avenues of social assistance and necessitated the augmentation of state-based welfare efforts. Moreover, applications to the Lee Camp soldiers' home indicate some of the cultural assumptions which informed the home's application process and demonstrate the duality of purpose that has often been regarded by historians as a key characteristic of Confederate veterans' welfare.  相似文献   
100.
We report a successful extraction and sequencing of ancient DNA from carbonized rice grains (Oryza sativa) from six archaeological sites, including two from India and four from Thailand, ranging in age from ca. 2500 to 1500 BP. In total, 221 archaeological grains were processed by PCR amplification and primary-targeted fragments were sequenced for comparison with modern sequences generated from 112 modern rice populations, including crop and wild varieties. Our results include the genetic sequences from both the chloroplast and the nuclear genomes, based on four markers from the chloroplast and six from the nuclear genome. These markers allow differentiation of indica rice from japonica rice, the two major subspecies of Asian rice (O. sativa) considered to have separate geographical origins. One nuclear marker differentiates tropical and temperate forms of subspecies japonica. Other markers relate to phenotypic variation selected for under domestication, such as non-shattering, grain stickiness (waxy starch) and pericarp colour. Recovery and identification of sequences from nuclear markers was generally poor, whereas recovery of chloroplast sequences was successful, with at least one of four markers recovered in 61 % of archaeological grains. This allowed for successful differentiation of indica or japonica subspecies variety, with japonica identified in all the Thai material and a mixture of indica and japonica chloroplasts in the two Indian assemblages. Rice subspecies was also assessed through conventional archaeobotanical methods relying on grain metrics, based on measurements from 13 modern populations and 499 archaeological grains. Grain metrics also suggest a predominance of japonica-type grains in the Southeast Asian sites and a mixture of japonica and indica in the Indian sites with indica in the minority. The similar results of grain metrics and ancient DNA (aDNA) affirm that grain measurements have some degree of reliability in rice subspecies identification. The study also highlights the great potential of ancient DNA recovery from archaeological rice. The data generated in the present study adds support to the model of rice evolution that includes hybridization between japonica and proto-indica.  相似文献   
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