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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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During the late prehistoric period (ad 1250–1550) in the southeast USA, when native populations transitioned to living in permanent, nucleated settlements practicing maize agriculture, most experienced a decline in health. However, some research shows that not all groups experienced the decline in the same way as there were regional differences in dental caries and iron deficiency anaemia frequencies and patterns of physical activity. Therefore, the purpose of this study is to determine if regional differences in health also existed between late prehistoric upland and coastal inhabitants from one part of the southeastern USA. Pathological lesion frequencies were calculated for 441 individuals from 23 upland archaeological sites and compared with previously published data for 340 individuals from 11 coastal sites. Significant differences in lesion frequencies were observed between upland and coastal groups. For example, upland adult men have more carious teeth among the maxillary first incisors, maxillary second molars, mandibular canines, and mandibular second molars. For women, greater caries frequencies are found among the maxillary first and third molars, mandibular first incisors, and mandibular third premolars. Upland children show higher percentages of caries for 14 tooth classes. Coastal juveniles have a greater frequency of porotic hyperostosis, and more of them exhibit an enamel hypoplasia. Periosteal lesion frequency is greater for the coastal group at the humerus, radius, femur, and tibia. Lesions indicative of degenerative joint disease are more often found on the thoracic spinal segment, sacrum and shoulder of upland men with upland women having more lesions at the cervical, thoracic, and lumbar spinal segments, the sacrum, and the shoulder. Taken together, these results show that adults from the upland region consumed more maize and lived a more physically demanding life while coastal adults struggled more with infection. Among children, more coastal inhabitants were anaemic and more of the experienced significant growth disturbances. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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Edmond Halley made two scientific voyages in the Atlantic Ocean as captain of the HMS Paramore between 1698 and 1700. Following these voyages he published the first map showing lines of equal magnetic declination in 1701. Halley did not reveal how he constructed the map, however, and it remains unknown. In this study, a construction procedure is hypothesized that uses mathematical tools that were available in his day, namely arithmetical averages and Isaac Newton’s method of divided difference for fitting a polynomial curve to data. To enable his map construction, a method is suggested whereby Halley could have created new data to augment the situations where insufficient data were collected.  相似文献   
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The post-war settlement among the policy elite is central to much historical literature. This article considers the rise and fall of the idea of ‘industrial democracy’, and its relationship to this settlement. The elite failed to respond coherently to claims for workplace democracy. The notion that politicians could work with ‘the unions’ and ‘industry’ was shown to be deficient. The unions contained numerous views, many hostile to industrial democracy in the form proposed by Bullock and the TUC. Industry was almost uniformly antagonistic. The notion of consensus ostensibly underpinned the attempts of Labour and Conservative politicians to progress this issue. In truth, this was a curious approach. The debate over Bullock was, at root, an argument over whether the owners of capital should cede some of their power in favour of organised labour. There was never likely to be agreement on this. The inconclusive debate over Bullock ultimately showed how fragile the consensus was. The political elite could not forever smooth over underlying disagreements between capital and labour, or between groups of workers with differing interests.  相似文献   
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