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71.
Three new species of the Araucariaceae are described from leaf remains, Araucaria readiae from the Early Eocene Regatta Point flora, A. hastiensis from the Middle-Late Eocene Hasties flora, and Agathis tasmanica from the Early Oligocene-Early Miocene Little Rapid River flora. Additionally, emended diagnoses are presented for Araucarioides linearis and A. annulata. A. readiae is the first organically preserved species in the section Eutacta described from Tasmania, A. hastiensis is the first record of a species not in section Eutacta in Tasmania, and A. tasmanica is the first record of Agathis in Tasmania. These species, along with other records from south-eastern Australia indicate the presence of a high diversity of araucarian species in the region in the Early-Middle Tertiary, although no species survive there today. Climatic change and competition from angiosperms may have led to their demise in that region.  相似文献   
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Neighborhoods and Fertility in Accra, Ghana: An AMOEBA-based Approach   总被引:1,自引:0,他引:1  
Fertility levels remain high in most of sub-Saharan Africa, despite recent declines, and even in a large capital city such as Accra, Ghana, women are having children at a pace that is well above replacement level and this will contribute to significant levels of future population growth in the city. Our purpose in this paper is to evaluate the way in which neighborhood context may shape reproductive behavior in Accra. In the process, we introduce several important innovations to the understanding of intra-urban fertility levels in a sub-Saharan African city: (1) despite the near explosion of work on neighborhoods as a spatial unit of analysis, very little of this research has been conducted outside of the richer countries; (2) we characterize neighborhoods on the basis of local knowledge of what we call "vernacular neighborhoods"; (3) we then define what we call "organic neighborhoods" using a new clustering tool-the AMOEBA algorithm-to create these neighborhoods; and then (4) we evaluate and explain which of the neighborhood concepts has the largest measurable contextual effect on an individual woman's reproductive behavior. Multi-level regression analysis suggests that vernacular neighborhoods are more influential on a woman's decision to delay marriage, whereas the organic neighborhoods based on socioeconomic status better capture the factors that shape fertility decisions after marriage.  相似文献   
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Domesticated rice, Oryza sativa L., though a perennial, is nowadays usually cultivated as an annual. This has led a number of commentators to misinterpret the historical record. The older view that rice was domesticated around the Bay of Bengal and in parts of mainland Southeast Asia has been replaced by competing views of earliest domestication in that region and in the Yangzi valley. Botanical considerations point clearly to the retention of perennial characteristics while archaeological and historical evidences point to cultivation with more than a single harvest from an initial planting – the practice of ratooning. Evidence is reviewed briefly for China and more extensively for Southeast Asia. Modern field evidence is used to support the notion that ratooning was probably more widespread in the past and that this practice may represent an early phase in the history of rice agriculture in Southeast Asia as it does in China.  相似文献   
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Drawing on and combining political science and legal frameworks, this article explores the validity of disenfranchising Australian prisoners. The authors examine and critically assess the various arguments used in Australia by both legislators and High Court Justices to defend the practice of disenfranchisement. Such arguments are assessed against liberal democratic principles as well as jurisprudence arising from cases in settings that provide protection for electoral rights in formal charters of rights. The authors show that in settings that entrench voting rights in the Constitution, any infringement attracts strict scrutiny from the courts. Courts insist that any abridgement of voting rights should serve a legitimate government purpose and be proportionate to that purpose. The arguments made for prisoner disenfranchisement by legislators in the Australian context invariably fail both parts of this test.  相似文献   
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BOOKS RECEIVED     
Art Gallaher, Jr. and Harland Padfield, Eds. The Dying Community. Albuquerque: University of New Mexico Press (School of American Research), 1980. xiv + 305 pp.

Nancy Dorian. Language Death: The Life Cycle of a Scottish Gaelic Dialect. Philadelphia: University of Pennsylvania Press, 1981. xiv + 206 pp  相似文献   
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