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The history of the introduction and dispersal of village chickens across the African continent is a subject of intense debate and speculation among scholars. Here, we synthesize and summarise the current scientific genetic and nongenetic knowledge in relation to the history of the species on the continent. Sociocultural, linguistic, archaeological and historic data all suggest a complex history for the species in Africa, characterized by multiple maritime and/or terrestrial introductions over time and several dispersal routes towards and within Africa. Molecular genetics information supports these observations and in addition suggests possible Asian centers of origin for African domestic chickens, including South Asia and Island Southeast Asia. However, both sets of data were until now too limited in their geographic scope, both within Africa and in comparison with chickens from Asia, to unravel the history of the species in detail. We anticipate that further continent-wide studies combining archaeological, ancient and/or modern genetic information may shed new insights on the history of the species. These will contribute to a deeper understanding of the history of trading networks and human interactions within Africa and between African and Asian societies, at the root of the development and expansion of African civilizations. 相似文献
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James P. Allan Marc J. O'Reilly Richard Vengroff 《The American review of Canadian studies》2013,43(4):497-519
Recent calls for a greater emphasis on the teaching of Quebec literature from primary school to cégep once more link the teaching of Quebec literature with the survival of a language and a culture. The current debate echoes those which have taken place over the last 100 years, both under the denominational system of education and since the Révolution tranquille. Different pedagogical and ideological factors have influenced not only whether Francophone Canadian literature has been taught, but also what has been taught and how it has been taught. Anxieties about the status, history and definition of “notre littérature” have recurred throughout the century, as have concerns about the relationship between the literature of Quebec and the literature of metropolitan France. This article will discuss the teaching of literature in Quebec since 1900 to conclude with a consideration of the teaching of Francophone Canadian literature in Quebec today. 相似文献
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