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1.
Evidence from several disciplines supports the proposition that following the Wisconsinan and an initial but brief moist phase of the Holocene, there was a gradual drying trend in the mid-continent Prairie Peninsula that peaked about 7000 years ago, a pattern that was not reversed until about 4000 years ago. Except for minor perturbations, conditions during the past four millennia have essentially been similar to those of the present. Studies in palynology and geomorphology have shown that the climatic regimes of the early/mid Post-glacial had a marked influence on both the biota and landscape erosional patterns, especially along the margins of the Prairie Peninsula. Measurable changes in the landscape and attendant biota show a time-transgressive pattern of drought related phenomena recorded palaeo-ecologically from west to east.Few studies of archaeological sites in the Prairie Peninsula have examined the evidence in and around the sites themselves for data reflecting local environmental dynamics. In fact, earlier models proposed for explaining the evolution of food-procuring systems in eastern North America virtually ignored potential changes in the natural environment. This paper examines data from two archaeological sites along the prairie-forest border in Missouri that contain long cultural sequences. Evidence is presented that pronounced changes in the natural environment occurred and that these biophysical variables are indeed critical for understanding the evolution of food-procuring societies in the American Midwest. 相似文献
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ABSTRACT This paper examines the role of the structure of transportation rates in the Weber-Moses triangle model. It shows that, in Zeigler's analysis, the appearance of the price elasticities of demand for inputs actually vanish by a simple application of the envelope theorem. Applying comparative statics analysis, we show when transportation rates are a function of quantity and distance, the assumptions that the production function is homogeneous of degree one and the transportation rates elasticities with respect to quantity and distance are constant are not sufficient to insure that the optimum location is independent of the level of output. This result is significantly different from that obtained by either Miller and Jensen or Zeigler. 相似文献
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Drid Williams 《Oceania; a journal devoted to the study of the native peoples of Australia, New Guinea, and the Islands of the Pacific》1987,57(4):314-315
Society and the Dance: The Social Anthropology of Process and Performance. Edited by Paul Spencer. Cambridge: Cambridge University Press. 1985. Pp. x + 214. Price: $A22.00 (paperback), $A66.50 (hardback). 相似文献
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