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991.
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   
992.
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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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   
999.
The Mesolithic communities of northwest Europe have generally been considered inherently mobile, and all the material evidence associated with them has been interpreted accordingly. This has resulted in entrenched, theoretically polemical and largely hypothetical mobility models, focusing on seasonal rounds and extraction activities. However, recent reanalyses of the ethnographic sources, and discoveries of both substantial and ephemeral Mesolithic structures, as well as new data from recent innovative lithic and scientific analyses (including DNA, isotope research on human remains, and geochemical analyses of lithic artefacts), have forced us to rethink the rather static models of Mesolithic mobility strategies. This paper, examining Mesolithic hunter-gatherer mobility and settlement models from Britain and Ireland, is part of that reassessment. In particular, it assesses the impact of the multiple lines of consilience on our understanding of Mesolithic habitation of landscapes. These include the archaeological evidence and the efficacy of recent theoretical and methodological approaches that have been employed to interpret it.  相似文献   
1000.
This paper aims to examine some societal principles that underlie the development of horse-drawn chariots in Inner Eurasia during the Middle and Late Bronze Age (cal. 2050–1750 BC). Analysis is based on an evaluation and re-examination of the archaeological evidence for horse-drawn chariots, and the social constructs they entail. Chariots were developed in the zone of the Northern Eurasian steppes before c. 2000 BC in the context of complex but stateless societies. Because chariots depend on a set of developed skills, valuable resources, and complicated technologies, which involve several outstanding improvements to previously known solutions, they require specific conditions for their development and maintenance in social life. Most fundamentally, they require a group of people with an interest in this complex technology: a class of military elites characterized by aggrandizing behavior. The competition between collectives of military elites for resources, power and prestige brought into life the earliest chariot complex in the world.  相似文献   
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