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Sarah K. Brown Christyann M. Darwent Benjamin N. Sacks 《Journal of archaeological science》2013,40(2):1279-1288
The domestic dog fulfills many functions for their human companions, such as hauling, guarding, and protection. Consequently, humans have taken dogs to nearly every corner of the globe. Recent translocations of Western dogs stemming from the Victorian era dog fancy have erased some of the ancient genetic signatures of these earlier migrations. Here we used DNA of ancient and modern dogs from the North American Arctic of Alaska and Greenland to assess their genetic continuity in time and space. We successfully sequenced 23 archaeological (ca. AD 1250–1910) and recent (ca. AD 1930–1990) surface-collected Canis bone and tooth samples and compared them to 51 modern Inuit Sled Dogs and to published sequences of modern Alaskan Malamutes (and additional Inuit Sled Dogs) to test for evidence of lineage replacement or genetic continuity through time. Ancient samples from Alaska and Greenland and modern sequences from Greenland all contained a high frequency of haplotype A31, which was previously described only in modern North American Arctic dogs. Thus, A31 was a common thread tying the entire North American Arctic together prior to European colonization and, in the Eastern Arctic, indicates genetic continuity between past and present dogs as well. However, A31 is rare in modern Alaskan dogs, consistent with post-colonization replacement by Eurasian matrilines. 相似文献
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Geography's debates about how to maintain a sense of morally responsible action often emphasise the problematic nature of caring at a distance, and take for granted particular kinds of moral selfhood in which responsibility is bound into notions of human agency that emphasise knowledge and recognition. Taking commodity consumption as a field in which the ethics, morality, and politics of responsibility has been problematised, we argue that existing research on consumption fails to register the full complexity of the practices, motivations and mechanisms through which the working-up of moral selves is undertaken in relation to consumption practices. Rather than assuming that ethical decision‐making works through the rational calculation of obligations, we conceptualise the emergence of ethical consumption as ways in which everyday practical moral dispositions are re‐articulated by policies, campaigns and practices that enlist ordinary people into broader projects of social change. Ethical consumption, then, involves both a governing of consumption and a governing of the consuming self. Using the example of Traidcraft , we present a detailed examination of one particular context in which self‐consciously ethical consumption is mediated, suggesting that ethical consumption can be understood as opening up ethical and political considerations in new combinations. We therefore argue for the importance of the growth of ethical consumption as a new terrain of political action, while also emphasising the grounds upon which ethical consumption can be opened up to normative critique. 相似文献
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Ancient Maya settlement patterns exhibit fractal geometry both within communities and across regions. Fractals are self-similar sets of fractional dimension. In this paper, we show how Maya settlement patterns are logically and statistically self-similar. We demonstrate how to measure the fractal dimensions (or Hausdorff–Besicovitch dimensions) of several data sets. We describe nonlinear dynamical processes, such as chaotic and self-organized critical systems, that generate fractal patterns. As an illustration, we show that the fractal dimensions calculated for some Maya settlement patterns are similar to those produced by warfare, supporting recent claims that warfare is a significant factor in Maya settlement patterning. 相似文献