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991.
992.
Abner Cohen 《Ethnic and racial studies》2013,36(1):23-41
This article argues that the theoretical problem of the new racism thesis, as originally formulated in the 1980s, was the account of the discursive change it proposed and the role and significance of Powellism in this process. In offering a modification of the thesis I highlight the significance of the use of anecdotal accounts of the plight of ordinary English people in areas of black settlement as central to the re-articulation of racialized common sense in Powellism. I go on to argue that the particular discursive form of the racialized anecdote is one that is developed within Parliamentary debates from at least the mid-1950s onwards and that Enoch Powell is not the author but the elite beneficiary of this ideological work. I suggest that this Commons' sense informs and makes possible the success of the campaign for exclusion of black Commonwealth migrants prior to Powellism, and that Powell fashions his own elite/populist version of such narratives in 1968. Offering an account of racism as a discursive fiction, I argue that the anecdotal form of political racism in post-war Britain is a political and ideological response to the public prohibition on 'race' talk in public space. In offering a tentative theory of post-'race' signification which is consistent with empirical evidence, I argue that the 'moment' of re-articulation of racism in post-war politics is one consistent with the evacuated space of the prohibited notion of 'old' racism. 相似文献
993.
994.
Most mainland New Zealand species ofGentiana are protandrous as are manyGentianaceae elsewhere in the world. Selfing has evolved in some species confined to areas where pollinator availability is limited by weather, for example, inG. lineata. InG. chathamica, endemic to the Chatham Islands, dichogamy has been lost without the evolution of selfing; instead the flowers are approach herkogamous. It is suggested that as herkogamous blossoms can both receive and dispatch pollen during a single insect visit, whereas dichogamous systems usually require two visits, such a system may have evolved inG. chathamica to maintain outcrossing in an area where prospects for insect pollination are poor. 相似文献
995.
The objective of this study was to quantify spatial and temporal variability of anguillid glass eel ingress within and between adjacent watersheds in order to help illuminate the mechanisms moderating annual recruitment. Because single fixed locations are often used to assess annual recruitment, the intra-annual dynamics of ingress across multiple sites often remains unresolved. To address this question, plankton nets and eel collectors were deployed weekly to synoptically quantify early stage Anguilla rostrata abundance at 12 sites across two New Jersey estuaries over an ingress season. Numbers of early-stage glass eels collected at the inlet mouths were moderately variable within and between estuaries over time and showed evidence for weak lunar phase and water temperature correlations. The relative condition of glass eels, although highly variable, declined significantly over the ingress season and indicated a tendency for lower condition A. rostrata to colonize sites in the lower estuary. Accumulations of glass eels and early-stage elvers retrieved from collectors (one to >1500 A. rostrata per collector) at lower estuary sites were highly variable over time, producing only weak correlations between estuaries. By way of contrast, development into late-stage elvers, coupled with the large-scale colonization of up-river sites, was highly synchronized between and within estuaries and contingent on water temperatures reaching c. 10−12° C. Averaged over the ingress season, abundance estimates were remarkably consistent between paired sites across estuaries, indicating a low degree of interestuary variability. Within an estuary, however, abundance estimates varied considerably depending on location. These results and methodology have important implications for the planning and interpretation of early-stage anguillid eel surveys as well as the understanding of the dynamic nature of ingress and the spatial scales over which recruitment varies. 相似文献
996.
997.
M. J. ROBERTS 《Zoological Journal of the Linnean Society》1983,77(3):217-291
A total of 36 spider species of the families Theridiidae, Tetragnathidae and Araneidae are recorded from Aldabra atoll. Of these, 26 are described as new, together with one new subspecies. The taxonomy of the new species is discussed and, for comparative purposes, five other species not from Aldabra are illustrated. One new synonymy is established. Records for each species are given with, in some cases, notes on biology. The possible biological significance of the egg sac strings found in some species is considered. Finally, the biogeographical affinities of the Aldabra species are briefly discussed. 相似文献
998.
999.
Jean Gaudant 《Geobios》1980,13(5):683-703
The study of fossil Fishes preserved in the «calcaires à Bythinies of Montmeyan, la Mourotte and Saint-Julien-le-Montagné basins (Var. France), makes possible the demonstration of their referal to the family Characidae: These Fishes, here mentioned as Eurocharax tourainei nov. gen., nov. sp., clearly differ from the Lower Eocene Characid fishes of Languedoc and Paris Basin by their set of teeth. The brackish condition of the “calcaires à Bythinies is taken into account for explaining the probable biogeographical history of these Fishes. 相似文献
1000.
报道我国园蛛科2新种:阿克苏园蛛Araneus aksuensis,皇冠扇蛛Zilla crown-ia。 相似文献