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The purpose of this paper is to emphasize the benefits of adopting non-destructive energy dispersive X-ray fluorescence (ED-XRF) as a first-order technique to determine chert whole-rock geochemistry for archaeological sourcing. Chemical signatures for the Touladi and La Martre prehistoric quarries from the lower St. Lawrence and Gaspé Peninsula region of Quebec, Canada, are determined and serve as references to test the provenance of regional chert artifacts. Chert experimental flakes, created from quarry geological hand samples, are analyzed and used to validate the method. Archaeological flakes and tools recovered from three archaeological sites are analyzed and tested against quarry samples. Geochemical diagrams and Principal Component Analysis are used to establish artifact-quarry relationships. The effects of surface weathering on the geochemical analysis of archaeological chert artifacts are presented. Sample restoration and research avenues are discussed and proposed to further enhance the robustness of future chert geochemical data sets. 相似文献
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Prehistoric behavioral depression of cormorant (Phalacrocorax spp.) on the northern California coast
Resource depression is often assumed to result from the over-exploitation of a prey species leading to declines in its population, and therefore availability, to human hunters. However, two other forms of resource depression are noted in the ecological literature: behavioral and micro-habitat depression. Data presented in this paper demonstrate resource depression of cormorants (Phalacrocorax spp.), a coastally breeding and semi-pelagic bird genus, at a coastal site in northern California. Citing modern cormorant behavior and a lack of evidence for intensive rookery exploitation, it is argued that the observed resource depression resulted from changes in cormorant behavior that decreased encounter rates for human hunters. Such behavioral depression is cited as a buffer to the extirpation of prey in mainland settings. 相似文献
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Adrian Green 《The Seventeenth century》2014,29(4):403-409
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Adrian J. Pearce 《Colonial Latin American Review》2013,22(3):422-440
The colonial mines of Huancavelica in central Peru boasted unique status, as the sole significant colonial American source of mercury, the main catalyst in the production of silver. This importance notwithstanding, Huancavelica remains relatively little known, in part because its historiography lies widely dispersed among journals and edited collections. This article seeks to facilitate further research by reviewing all significant existing work on the mines (more than eighty publications in total). In doing so, it provides a new guide to the history of Huancavelica, designed primarily to highlight major areas still requiring the attention of scholars. 相似文献
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G. Michael Taylor Soren Blau Simon Mays Marc Monot Oona Y.-C. Lee David E. Minnikin Gurdyal S. Besra Stewart T. Cole Paul Rutland 《Journal of archaeological science》2009,36(10):2408-2414
We have amplified Mycobacterium leprae DNA from the skeleton of an adult human female exhibiting signs of lepromatous leprosy (LL). The remains were excavated from the site of Devkesken 6 on the Ustyurt plateau of Uzbekistan and date to between the 1st and 4th centuries AD. Recovered DNA was fragmented but of sufficient quality and quantity to allow a series of biomolecular genotyping methods to be applied. These methods included variable nucleotide tandem repeat (VNTR) typing of two microsatellite and one minisatellite regions and also single-nucleotide polymorphism (SNP) typing for nine informative loci.Genotyping showed that the causative strain of M. leprae exhibited a SNP-type 3 profile, characteristic of cases associated geographically with Europe and North Africa. Further SNP sub-typing was performed and the data obtained from the Uzbek leper was compared with the same loci amplified from a case of LL recovered from Blackfriars, Ipswich, UK dating to between the 13th and 16th centuries AD. Unique group 3 subtypes were found in both the Uzbek case and Ipswich 1914. These appear to be ancestral to recent type 3 strains. Mycolic acid analysis confirmed the presence of M. leprae in the Uzbek samples. Phylogenetically informative SNPs and other polymorphic loci will contribute to the study of human migrations, as well as the origin and spread of leprosy. 相似文献