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The recovery of ancient DNA from archaeological wheat samples under different preservation conditions was assessed using a number of genetic markers. It was possible to amplify nuclear DNA from desiccated grains but not from charred. The desiccated grain was from a pre-Hispanic grain silo in Gran Canaria and showed excellent DNA preservation, enabling the amplification of the ribosomal DNA markers IGS and ITS, the upstream region of the HMW-glutenin locus and single-locus nuclear microsatellites. Our results demonstrated the presence of both durum and bread wheat in an assemblage of naked grain. We were also able to identify different genotypes in durum wheat and compare these with extant landraces, providing insights into the agrarian practices of the ancient Canarians and the origin of their crops.  相似文献   
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Memories are crucial to our construction of place. They simultaneously offer an anchor for identity and different temporalities to encounters with landscapes. Memory allows different spaces, pasts, and futures to become embedded in particular locales. Yet the spontaneous assemblages of meaning that memory enables are not apolitical. Thus the mechanisms and processes by which meaning is articulated in these encounters are fundamental to our understandings of place. This paper, therefore, brings together the work of Henri Bergson on memory and Paul Ricoeur on narrative, to examine the stories individuals produce which define the self. By drawing on research into the lives of young people in the countryside, the paper does three things: it discusses the role of memory in creating identity; it examines the political process of narrative by which memories become woven into understandings of place and create a bricolage of the here; and finally, it offers the ‘storied-self’ as a resolution of the competing constructions and experiences of personal continuity and the inconsistencies and constant change in the project of the individual.  相似文献   
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Relict arable soils dating fromc.AD700 provide an opportunity to identify early arable land management practices in the agriculturally marginal landscapes of the Lofoten archipelago, northern Norway. Synthesis of field survey and soil thin section micromorphology supported by image analysis suggests that there was deliberate management of erodible sandy soils in sloping locations to create small areas of cultivation terrace, with a range of materials used as soil amendments to stabilize the accumulated soil and enhance fertility. Small areas of sandy soils in more gently sloping locations were also cultivated, again with a range of materials used as amendments and which contributed to a significant increase in soil thickness. The last phase of cultivation commenced during the late 1800s and involved the reclamation of wetter, peaty soils by spade. These patterns of arable land management are repeated in different parts of Lofoten and indicate that despite the climatic and economic marginality of arable activity in Lofoten, land management practices were developed and applied to permit barley production from small areas.  相似文献   
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