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This study uses quartz-based optically stimulated luminescence dating to determine when a massive fortification wall (W11186) was constructed in the archaeological site of Tall Zarʿa in the Jordan Valley. A total of 11 samples of sediments were taken from a trench on the north side of the wall (extramuros). The extracted quartz grains had good luminescence characteristics and were identified as well bleached by comparison with feldspar infrared-stimulated luminescence (IRSL) ages. The optical ages showed that the deposition against the wall occurred in two different periods. The first was around 3.20 ± 0.07 ka ago (Iron Age), and the second was around 2.28 ± 0.08 ka (Hellenistic period). Human activity was evident because of the intermixing of cultural material with the presumed naturally deposited units.  相似文献   
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ABSTRACT The paper explores the socially salient contrast between ‘mainlanders' and ‘saltwater people’ in the Buka area in the Autonomous Region of Bougainville, Papua New Guinea, as observed during ethnographic fieldwork in 2004–05. Buka people themselves articulate three at first sight disparate points of contrast between mainlanders and saltwater people. These concern settlement patterns, predominant subsistence activities and different degrees of ancestral knowledge. This paper explores these points and aims to specify their interconnection from the perspective provided by a fourth contrast established ethnographically, that between different modes of objectifying relations on the mainland and ‘at sea’. With a detailed investigation of the ethnographic ‘surface’ of the phenomenon, the paper aims to provide a basis for future in‐depth analyses of various aspects of the mainland‐saltwater contrast in the context of Bougainvillean politics and the sustainability of livelihoods in the area.  相似文献   
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In 2010, the complete mitochondrial genome of a fossil hominin from Denisova Cave, Altai was sequenced on the basis of mtDNA extracted from the hand phalanx of a girl. Modern micro tomographic techniques mark a new stage in the morphological study of extant and fossil hominins, offering opportunities to work with fragmentary material. We have used the nondestructive method of micro computerized tomography for a comparative histological assessment of the Denisova girl's biological age. The diaphyseal and metaphyseal parts of the phalanx, reflecting different ontogenetic stages, were undergoing rapid growth. The histological pattern of the walls of the diaphysis, specifically the lamellar structure with rare osteons, indicates a stage corresponding to 6–7 years in modern children. An altogether different pattern, resembling that of adults, was earlier observed in a Neanderthal child from Okladnikov Cave, Altai. The resemblance between the Denisova individual and extant humans in certain features of growth and skeletal maturation may point to the very early origin of the modern skeletal growth pattern. The Neanderthal pattern is quite distinct and may have originated after these hominins had branched off from the common stem.  相似文献   
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Recent investigations of three archaeological sites in the Nigerian part of the Chad Basin during the Holocene reveal key stages in the cultural development and environmental history of that region. At Dufuna, a dugout boat was dated to around 6000 BC, making it the oldest known boat in Africa and one of the oldest in the world. Boats may thus have contributed to the mobility of the population of the southern edge of the Sahara 8000 years ago and, thereby, to the cultural homogeneity of this period. The pottery site at Konduga is around a thousand years younger than Dufuna but still belongs to the time of Mega-Chad. The site is on the Bama Ridge, an old shoreline. Its pottery, decorated in the Saharan tradition, belongs to the earliest ceramic phase of the West African Later Stone Age, long before the beginnings of food production. Although this site was probably settled by pioneers advancing into a largely flooded landscape along the slightly raised shoreline, the human occupation of the area previously covered by Mega-Chad began along a broad front around 2000 BC. Archaeological and palaeoecological finds from two settlement mounds at Gajiganna are described as case studies for this phase, which predates the well-known site of Daima.
Résumé Les résultats présentés proviennent de recherches récentes sur trois sites archéologiques, dont chacun représente un épisode clé du développement culturel et de l'histoire environnementale du Bassin nigérian du Tchad au cours de l'Holocène. A Dufuna, la découverte d'une pirogue monoxyle, datée d'environ 6000 ans BC, constitue le témoignage le plus ancien d'une embarcation en Afrique et l'un des plus ancien dans le monde. Ce moyen de transport indique la mobilité des populations de la marge sud du Sahara à l'Holocène inférieur et moyen; ce qui a dû contribuer à l'homogénéité culturelle de cette période. Le site à poterie de Konduga est le plus jeune d'un millénaire que Dufuna, mais appartient à l'époque du Méga-Tchad. Le site est installé sur une ancienne ligne de rivage, la Bama Ridge. Sa poterie, décorée selon la tradition saharienne, appartient à la plus ancienne phase à céramique du Later Stone Age ouest-africain, bien avant le début d'une production alimentaire. Vu que ce site ne devait étre occupé que par des pionniers aventurés dans un paysage largement amphibie à la faveur d'un mince cordon émergé, la colonisation de l'espace antérieurement couvert par le Méga-Tchad, débute le long d'un large front vers 2000 ans BC.Les trouvailles archéologiques et paléoécologiques de deux tertres anthropiques à Gajiganna sont décrites commes études de cas illustrant cette phase, qui précède celle du célèbre site de Daima.
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The close link between scientific knowledge, learning, and beliefs is particularly relevant in environmental policymaking and the interaction of environmental with economic development‐focused policies. This article contributes to a more refined understanding of the links among scientific knowledge, belief changes, and the move from a collaborative to an adversarial policy subsystem within the Advocacy Coalition Framework. It analyzes the process of drafting and negotiating the biofuels aspects of the European Renewable Energy Directive, which was dominated by political disagreements between two advocacy coalitions. Their initial agreement on increasing the share of renewable energies in transport turned into conflict after new scientific evidence emerged on the negative environmental and climate change impacts of crop‐based biofuels. The environmental coalition changed its empirical policy beliefs to reflect normative policy beliefs on environmental protection. This change in empirical policy beliefs uncovered a pre‐existing conflict with the normative policy beliefs of the economic development‐focused coalition. As a consequence, the collaborative policy subsystem shifted to an adversarial policy subsystem.  相似文献   
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