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31.
This paper considers the transition from Howiesons Poort to post-Howiesons Poort technologies at the rock shelter site of Klein Kliphuis, South Africa. The transition at this site is shown to be gradual, with incremental changes in material selection and in the size and shapes of flakes and cores. Implements which appear to blend characteristics of those distinctive of the earlier and later industries appear briefly at the mid-point of the transition. The results suggest that there is unlikely to have been an occupational hiatus between the Howiesons Poort and post-Howiesons Poort. Explanations for the Howiesons Poort phrased in terms of population expansion and contraction are also difficult to support. Technological changes at this time may relate to environmental variation, though the limited nature of terrestrial archives documenting changes in resource productivity necessitate that any such suggestion be made with caution. 相似文献
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Abstract Quantitative methods of content analysis have become established in most subfields of political science, but remain relatively unutilized in studies of political theory, despite the exclusive focus of that subfield on textual sources. This article develops a variation of content analysis—termed usage analysis—and employs it to resolve a standing debate in scholarship on Cicero's political theory regarding the synonymy of the major Latin terms for the state (civitas and res publica). The resulting distinction between these concepts then informs an exposition of Cicero's ideal state not as the Roman Republic itself or the mixed constitution alone, but as a universal, everlasting political society supported by justice, a mixed constitution, and active citizenship. 相似文献
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Domestic Pigs in Africa 总被引:1,自引:0,他引:1
Marcel Amills Oscar Ramírez Ofelia Galman-Omitogun Alex Clop 《African Archaeological Review》2013,30(1):73-82
The history of African pig breeds is still controversial due to the relative scarcity of archaeological and genetic data clarifying their origins. While these breeds might descend from Near Eastern pigs entering the continent via Egypt during the Neolithic, Africa may be a primary domestication locus for pigs, as indicated for other species such as cattle and donkeys. In this regard, characterisation of the mitochondrial gene pool of African pig breeds has revealed a very low frequency of Near Eastern alleles, suggesting that, if Fertile Crescent pigs played a part in the foundation of African breeds, their genetic signature has been substantially erased. Interestingly, genetic analysis of western and eastern African pig breeds has revealed a strong phylogeographic pattern, with the latter harbouring Far Eastern alleles at high frequencies. This finding is consistent with data obtained for chickens and confirms that livestock was transported in ancient times, from the Far East to Africa as a consequence of the Indian Ocean trade. European colonisation of Africa also involved the introduction of exotic swine breeds such as Iberian pigs. The confluence of the highly divergent European and Far Eastern Sus scrofa gene pools contributed to significantly enrich the genetic reservoir of African swine breeds, favouring their adaptation to environmental conditions that are often harsh. Conservation of this genetic legacy will be of utmost importance to ensure the prosperity of current resource-based subsistence farming systems in Africa. 相似文献
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Alex G. Cook Robert B. Blodgett R. Thomas Becker 《Alcheringa: An Australasian Journal of Paleontology》2013,37(3):181-207
Over 50 identifications of Tertiary pollen are reviewed. The pollen assemblages indicate rain-forest through most of the Tertiary, but the requisites for pollen preservation are biased towards the wetter climates. The present day geographical affinities of the botanical groups are largely with taxa of the tropical zone and Australia-wide taxa. There is geographic variation in the fossil pollen assemblages when southeastern Australia is compared with Central Australia and Queensland. The major changes in the fossil floras coincide with climatic change, indicating the influence of climate on the evolution of plant assemblages. The older phytogeographic concepts are inappropriate for the fossil record, especially when considered in conjunction with palaeoclimates and palaeogeography. It is unfortunate that palynology has given little information of the evolution of floras in drier climatic regimes, or of the evolution of the eucalypts. 相似文献
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Neil S. Davies Ivan J. Sansom Robert S. Nicoll Alex Ritchie 《Alcheringa: An Australasian Journal of Paleontology》2013,37(4):553-569
The Stairway Sandstone is a 30–560 m thick succession of Middle Ordovician siliciclastic sedimentary rocks within the Amadeus Basin of central Australia, deposited in the epeiric Larapintine Sea of northern peri-Gondwana. The Stairway Sandstone is significant as one of only two known Gondwanan successions to yield articulated arandaspid (pteraspidomorph agnathan) fish. Herein we use the ichnology of the Stairway Sandstone to reveal insights into the shallow marine habitat of these early vertebrates, and compare it with that of other known pteraspidomorph-bearing localities from across Gondwana. The Stairway Sandstone contains a diverse Ordovician ichnofauna including 22 ichnotaxa of Arenicolites, Arthrophycus, Asterosoma, Cruziana, Didymaulichnus, Diplichnites, Diplocraterion, ?Gordia, Lockeia, Monocraterion, Monomorphichnus, Phycodes, Planolites, Rusophycus, Skolithos and Uchirites. These ichnofauna provide a well-preserved example of a typical Ordovician epeiric sea assemblage, recording the diverse ethologies of tracemakers in a very shallow marine environment of flashy sediment accumulation and regularly shifting sandy substrates. New conodont data refine the age of the Stairway Sandstone to the early Darriwilian, with ichnostratigraphic implications for the Cruziana rugosa group and Arthrophycus alleghaniensis. 相似文献
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Alex Gibson Sheena Asthana† 《Transactions (Institute of British Geographers : 1965)》2000,25(3):303-319
Notwithstanding the recent change of government, UK educational policy continues to stress school performance tables, parental choice and competition – reflecting an acceptance by New Labour of Tory notions concerning the role that market mechanisms play in improving school performance. In view of the 1997 Education White Paper's insistence that the new government's goal was to 'overcome the spiral of disadvantage … passed from one generation to the next', this implies that the DfEE remains unimpressed by long-standing arguments concerning the socially-divisive consequences of market forces in education.
This paper seeks to add empirical weight to this debate. Arguing that recent analyses of aggregate levels of social stratification have masked polarization occurring at the local level, our analysis places schools in the context of the local markets within which they operate. This yields clear evidence that educational markets tend to exacerbate existing differences between schools in terms of both their performance and social status. 相似文献
This paper seeks to add empirical weight to this debate. Arguing that recent analyses of aggregate levels of social stratification have masked polarization occurring at the local level, our analysis places schools in the context of the local markets within which they operate. This yields clear evidence that educational markets tend to exacerbate existing differences between schools in terms of both their performance and social status. 相似文献
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