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The need for experiments to study physical aspects of craft of the past is stated, as well as the necessity for them to have clear aims and to follow the established principles of scientific enquiry. These principles are discussed in this joint paper by ten maritime archaeologists and others, together with methods and some points of management critical to their application in this field.  相似文献   
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We review evidence from human biology—paleopathological and isotopic paleodietary studies on ancient Maya skeletons—to assess the validity of ecological models of the Classic Maya collapse, in which elevated disease and deteriorating diet are commonly assumed. To be upheld, the health arguments of ecological models require that the Maya disease burden (1) was greater than that for many other societies and (2) increased over the span of occupation. The dietary argument requires (1) consistent change in diet from Preclassic and Early Classic Periods to the Terminal Classic and (2) increasing social divergence in diet. A correlation between diet and disease is necessary to link these arguments. Neither pathology nor isotopic data consistently support these criteria. Instead, it appears that local environmental and political factors created diversity in both disease burden and diet. In view of the human biological data, we are skeptical of ecological models as generalized explanations for the abandonment of Classic Maya sites in the southern lowlands.  相似文献   
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Madagascar's culture is a unique fusion of elements drawn from the western, northern, and eastern shores of the Indian Ocean, and its past has fascinated many scholars, yet systematic archaeological research is relatively recent on the island. The oldest traces of visitors are from the first century AD. Coastal settlements, with clear evidence of ties to the western Indian Ocean trading network, were established in several places over the next millennium. Important environmental changes of both plant and animal communities are documented over this period, including the extinctions of almost all large animal species. Urban life in Madagascar began with the establishment of the entrepôt of Mahilaka on the northwest coast of the island in the twelfth century. At about the same time, communities with ties to the trade network were established around the island's coasts. From the fourteenth to the sixteenth century, social hierarchies developed in several regions of the island. During the succeeding two centuries, Madagascar saw the development of state polities.  相似文献   
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One of the major features of the continental geography of North America that was still misunderstood at the beginning of the nineteenth century was the drainage system between the Mississippi River and the Pacific. At the beginning of the century, Americans thought of the drainage system as symmetrical, with all major streams heading in a common source region and flowing in several directions to the Mississippi, the Arctic, the Pacific and the Gulf of California. The desired water route across the continent was based upon this view. During the first half of the nineteenth century the concept of the common source region and the water route underwent revision. Geographical information from early explorers like Lewis and Clark and Pike reinforced the older theories but gradually gave way before more accurate data acquired by the men of the Rocky Mountain fur trade. The fur trade lore was tested by John Charles Frémont in the 1840's and a new image was developed, one of a continental divide rather than a common source region. Although the idea of a commercial route across the continent still persisted after Frémont, it was viewed as a land route, crossing the Continental Divide at South Pass, rather than one by water.  相似文献   
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