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Isotopic analyses of incrementally developed dental tissues can be used to reveal patterns of movement and diet in animals. However, the suitability of these methods for the reconstruction of herd movements has not yet been demonstrated. Inter-individual behavioural and isotopic variability at the herd scale, and the implications for archaeological and palaeocological applications, can only be demonstrated through the testing of modern animals. In this pilot study, dual-element isotopic profiles were created from incrementally developed dental tissues of five individuals selected from a modern herd of migratory Alaskan caribou (Rangifer tarandus granti). Enamel from second and third molars from the individuals was sequentially sampled in order to reconstruct time-series isotopic profiles. Variation in the strontium (87Sr/86Sr) and oxygen (δ18OCARB) isotope ratios of sequentially sampled enamel were compared to documented herd movement patterns and local geological and environmental conditions. Four individuals displayed the same general trends, although absolute isotopic values varied. One individual displays a very different trend and may represent a behavioural outlier or an immigrant from a semi-domesticated reindeer herd. The implications of this study to herd movement reconstruction in the past are discussed.  相似文献   
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Stable isotope analyses of modern coastal and salt-marsh plant species (‘salt-loving’ plants or halophytes) have demonstrated that these are significantly enriched in 15N compared to other terrestrial plants. Coastal salt-marshes were far more extensive in the past than they are today. They represented a vast and much-exploited resource in many areas of the UK and north-western Europe and were considered to be prime land for the grazing of animal stock.  相似文献   
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The penetration by western capitalism of the pre-capitalist world laid the foundations for an externally oriented, distorted and dependent form of development. This occurred through the subordination of indigenous societies and the highly selective exploitation of local resources by foreign capital. The means by which this occurred are directly expressed in the historical evolution of an underdeveloped country's space-economy. The case study of Fiji is used as an illustration of this process.  相似文献   
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