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The advent of new techniques of dental ageing has permitted inferences about the age-structures of ancient animal populations on the basis of faunal remains. Unfortunately, inference from archaeological populations of faunal elements to the age-structure of ancient herds is fraught with both sampling problems and logical difficulties. The relationship between a living herd—a dynamic system characterized by growth—and a static archaeological population is more complex than that assumed by current models based on kill-off patterns and survivorship curves. Using a computer simulation, these logical relationships are explored, and the effects of herd growth on the composition of live and death populations are evaluated. By employing the simulation within a deductive framework, constrained by ethnographically derived criteria for reproduction, mortality, and economic viability in the Near East, it is possible to determine whether certain archaeological kill-off patterns could represent viable herding systems. Examples were found to vary widely in terms of both demographic plausibility and economic viability. Some implications for the possible course of ova-caprine domestication in the Near East are discussed.  相似文献   
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A new and recursive algorithm for determining proximal polygons is based on quadtree concepts. The algorithm can use any distance metric, and produces a quadtree of the image of the proximal polygons. This can be converted to vector form, or be incorporated directly into a quadtree-based geographic information system, in order to solve a number of closest-point problems. The algorithm can also produce the Delaunay triangulation, which is the dual of the proximal polygons. Empirically, the running time of the algorithm is proportional to the number of centers raised to the 1.6 power.  相似文献   
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243 blacksmiths in Sierra Leone were interviewed in 1984-85 in an effort to focus on both the activities and attitudes of traditional blacksmiths in the country's economy. Due to the fact of an shortage of foreign exchange with which to import and maintain equipment, agriculture using high-technology equipment accounts for less than 15% of total production. Consequently, blacksmiths are vital to the nations' survival, despite prevailing attitudes toward them. The interviews were conducted in 9 of the 12 districts in Sierra Leone. The blacksmith operates not simply in terms of producing and servicing goods; cultural values frame his position in the community. In all of West Africa, and particularly among Mende-related peoples, there historically exists a mystique surrounding a blacksmith. In some societies, blacksmiths were believed to be witches. The arguments that most likely could account for this would probably lie in the fact that the blacksmith made farm tools and weapons of war, means of survival in the community. Thus, his position was vital. Traditionally the importance of the smith's profession lies in the fact that some of the implements he fabricates and the materials he uses are believed to provide elements of social control or to have healing powers. An appreciation of the cultural significance of the blacksmith demonstrates the degree of attachment of the population to this profession as well as the context within which one could relate to possible technological changes in the trade. An attempt was made in the interview to gather some information about levels of production. The figures represent averages, and production capacity varied owing to a number of factors, including the degree of organization of the unit, the capacity of the head of the forge to keep his team busy when work was intensive, and the degree of energy and determination of an operator to get the greatest amount of work done in 1 day. The most obvious factor influencing production levels was the size of the units. Pricing of commodities and the blacksmith's services depended on a combination of factors, but, generally, in semi-urban areas, where more impersonal relationships tended to obtain, prices appeared relatively more fixed than in rural areas. All smiths interviewed complained about the increasing scarcity of scrap iron. As there is every reason to envisage a continued dependence on informal-sector production by blacksmiths, official attitudes need to take these trades more seriously.  相似文献   
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Biogeographers, ecologists, palaeontologists, and conservation managers often deal with checklists in which not all individuals have been identified to a species level, or the accuracy of species identification is questionable. Is it possible and credible to investigate species richness based on such checklists? Studies on macrofauna in the Far Eastern seas, eastern Arctic seas, and adjacent waters of the Pacific and Arctic Oceans suggest that in different habitats and for diverse taxa, species, and higher taxa richness strongly correlate with each other and increase with an expansion in the study area and sample size according to the species–area law. Such an increase is higher in the bottom zone than in the pelagic. Species and higher taxa richness also show a decrease from lower to higher latitudes, which is in line with the Humboldt–Wallace’s law. According to Willis’ law and self-similarity in the organisation of taxonomic levels, species richness can be assessed based on the genus, family, and order richness. In other words, supraspecies richness itself can tell us the same as species richness and therefore certain global patterns revealed at the species level may also be revealed at the supraspecies level. Such a concordance in general trends among richness parameters at different taxonomic levels in practice implies that species richness can be studied based on lists that lack species identifications or lists with doubtful species identification. We suggest bolder use of supraspecies richness in science and practice, discussing the disadvantages and advantages of this approach.  相似文献   
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This article focuses on the particular moment of the 1945 United Nations charter meeting as a catalyst for a shift in Mary McLeod Bethune's feminist thought. The meeting, where Bethune served as the only African American female delegate, signalled a change in Bethune's thinking about equality for black women, so she used the founding of the United Nations as a platform to promote black women's alliances with other women of colour. Her idea was to reframe black women as citizens of the world, thus putting them in a numerical and ideological majority rather than keeping them in a minority position. Bethune has often been viewed as a reformer of race and gender issues in the early twentieth century, but a focus on her activism has hidden the intellectual contributions that she made to a form of black feminism that emerged out of her work with other clubwomen and through the United Nations in the 1920s through the 1950s. Specifically, this article argues that Bethune's intellectual work created a framework for African American women's feminism that emphasised anti-colonialism and their global alliance with other women of colour throughout the world.  相似文献   
120.
This paper is a statistical and geological study of the results of analysis of flint from British and West European flint mines, carried out by emission and atomic absorption spectroscopy. Groups of flint specimens were studied from each geographically separate flint mining area. Flints were analysed for a group of easily measured trace elements shown by previous work to be generally present. The ratios between the trace elements form a consistent pattern for each flint mine and statistically valid differences of pattern can be recognized between different flint mines. A geological investigation shows that the measured trace elements may be derived from clay minerals and explains geographical and statistical variation in the composition of flint in terms of its mode of origin in the chalk. An advanced statistical technique allows individual flint specimens of unknown origin to be attributed by their composition to one or other of the identified flint sources. The archaeological implications of this study are discussed.  相似文献   
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