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971.
While pioneers of archaeology in any given region have established the foundations of the discipline, their views have not remained unchanged in places such as Europe, North America and Australasia. In these regions, successive generations of researchers changed the direction of their work based not just on new observations but also in light of new methods and theories. For example, the idea of a Bronze Age revolution popularised by V. G. Childe in Europe was superseded by multiple alternatives over the years. In southern African Iron Age studies, John Schofield, Gertrude Caton-Thompson, Roger Summers, Keith Robinson and Peter Garlake created an impressive platform upon which successors could build. Confronting firm disapproval from more experienced researchers in the early 1980s, Huffman speculated that the evolution of sociopolitical complexity in our region was a linear relay from Mapungubwe to Khami via Great Zimbabwe. This position was sustained as the conventional wisdom largely, we argue, because no new research was being carried out in key areas of the region, and too few students, in particular African ones, were being trained to expand the focus of investigation. Here, we present new data to support our argument, that the pathway to sociopolitical complexity in southern Africa was multilinear. We propose looking forward rather than back, and to continue to seek the exposure of scales of interaction between multiple but chronologically overlapping entities associated with the rise of sociopolitical complexity in southern Africa.  相似文献   
972.
Grass silica short cell phytoliths were sampled from the four lowermost archaeological strata in excavation 1 at Wonderwerk Cave and offer an independent record of climatic change during an episode of Early Stone Age hominin occupation at the cave. Linked to differences in growing season temperature and the geographic distribution of C3 and C4 grasses in southern Africa, fossil grass phytoliths were used to trace palaeoenvironmental shifts at the site. The results suggest that Early Pleistocene environmental conditions at the cave fluctuated: between wetter and drier summer–rainfall growing conditions (C4) towards the end of the Olduvai subchron and the beginning of the subsequent interval of reversed polarity, to mostly dry and cooler winter–rainfall growing conditions (C3), that continued throughout the interval. It ended with a shift towards increased summer rainfall aridity at around one million years ago. The fluctuation between markedly wetter and drier C4 conditions at the cave (NADP-me grass types vs. NAD-me grass types) does not support the premise that the expansion of C4 grasslands was always coupled with increased aridity.  相似文献   
973.
The discovery of Kef en-Naga site, an open-air human occupation in northeastern Algeria, was favored by a sandstone quarrying where work truncated much of the archaeological sequence on its cross-section. A multidisciplinary rescue excavation conducted on this site provided, for the first time in the region, the evidence of superimposition of two stratigraphic levels (lower and upper) of sandy clay deposits formed in humid paleoenvironmental conditions. Besides, XRD analysis show that a large amount of hematite (Fe2O3) is localized at the lower level of the stratigraphic section, where iron is found in oxide form due to the moisture. As for rock magnetic property characterization analysis, the various magnetic parameters have strong values in the upper level, and the grains are small-sized. However, various magnetic parameters are lower at the lower level and the magnetic grain concentration is reduced. Although the site is lacking faunal and carpological remains, thereby depriving us of reliable dates, the two stratigraphic levels are correlated to the Holocene according to archaeological and paleoenvironmental considerations. The lower level likely corresponding to an early Epipaleolithic culture marked by the production of microliths using a microburin blow technique, while the upper level is related to a subsequent Epipaleolithic phase, characterized by the disappearance of microburin blow technique, the dominance of an industry on flakes and the existence of pressure debitage.  相似文献   
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This article proposes a different approach to the long generation controversy that divided naturalists in eighteenth-century Europe between those in favour of preformationism, on the one hand, and supporters of the theory of epigenesis on the other. This controversy has mostly been studied through the publications of the intellectual elite, that was constituted of medical doctors, natural historians, philosophers, and theologians. Rather than reviewing the ideas and antagonisms of the direct agents of the controversy, I will attempt to approach it from the margins. What is the legacy of a long-term controversy when it seems to be over? How was such an extended controversy perceived by contemporaries that would only have a fragmented access to quarrel? What is the role of scientific disputes in the education of doctors? I will address these questions by analyzing four essays written by medical students of the Royal Medical Society of Edinburgh.  相似文献   
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978.
Hardly any other city in North Rhine-Westphalia has such a green image as the city of Münster. It embodies the image of a livable city in Germany. Other North Rhine-Westphalian cities also work on their external perception and are approaching the task of getting a greener image for themselves in many ways. A central question is how it is done precisely and whether urban green infrastructure can be a locational factor to affect location-based marketing. This article deals with the strategies of various cities in North Rhine-Westphalia.  相似文献   
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