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91.
Microcredit is a concept that has gained widespread acceptance by international development agencies and major donors. It is viewed as a way to correct both governmental and market failure in Sub-Saharan Africa. Many view microcredit as a method for linking the formal and informal sectors of African economies to increase the reach of the formal sector. Extending the reach of the formal economy through microcredit is possible, and desirable, depending on macroeconomic reforms, respect for traditional financing relationships, and local control of institutions. However, very little has been done to determine the extent to which microcredit programs actually increase economic well-being. The model program, Grameen Bank of Bangladesh, has been studied and evaluated, but replications may not be inherently successful. The literature accepts that microcredit will increase economic well-being, if programs are correctly designed. Program design issues cannot be resolved, however, until economic well-being is measured and associated with specific designs.  相似文献   
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Arguments about genocide played a central role in how the government of Biafra and its supporters framed Biafran assertions of independence. Claims that genocide was occurring first cited violence directed against Igbos in northern Nigeria during 1966, before expanding to include both Nigerian military action against civilian targets in Biafra and the use of starvation as a weapon of war. Belief in Nigeria's genocidal intentions became a central tenet of emergent Biafran nationalism, and drew on both distorted representations of Nigeria and on historical analogies with the Nazi genocide against Jews. While the determination by a team of international observers that genocide was not occurring eroded the persuasiveness of Biafran genocide claims abroad, it did little to undercut Biafrans' belief that they were marked for extermination.  相似文献   
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ABSTRACT

Shellfish are a crucial resource for past and present subsistence-level societies around the world. Despite the diversity of environments in which shellfish are exploited, an examination of the global patterns of shellfish exploitation reveal surprisingly common patterns in the opportunities allowed and constraints imposed by relying on shellfish. These commonalities, linked to the fundamental features of shellfish and their exploitation, can illuminate diverse social and ecological factors likely to influence variability in their archaeological signatures. Here we review contributions to this special issue and explore common trends in shellfish use and its archaeological consequences.  相似文献   
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ABSTRACT

Archaeological evidence of shellfish exploitation along the coast of Sahul (Pleistocene Australia-New Guinea) points to an apparent paradox. While the continental record as a whole suggests that human populations were very low from initial colonization through early Holocene, coastal and peri-coastal sites dating to that time are dominated by small, low-ranked, littoral taxa to the near-complete exclusion of large, higher ranked, sub-littoral species, precisely the opposite of theory-based expectations, if human populations and predation rates were indeed as low as other data suggest. We present a model of shellfish exploitation combining information on species utility, transport considerations, and prey life-history that might account for this apparent mismatch, and then assess it with ethnographic and archaeological data. Findings suggest either that high-ranked taxa were uncommon along the Pleistocene coastlines of Sahul, or that abundant and commonly taken high-ranked prey are under-represented in middens relative to their role in human diets largely as a function of human processing and transport practices. If the latter reading is correct, archaeological evidence of early shellfishing may be mainly the product of subsistence activities by children and their mothers.  相似文献   
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To investigate potential human impacts on California Channel Island shellfish stocks over the past 10,000 years, we measured 1718 owl limpet shells from 19 archaeological components on San Miguel Island. Inhabiting the middle intertidal zone of Pacific Coast rocky shores, owl limpets are slow-growing mollusks that can live for 30 years and reach lengths of over 100 mm. Recent ecological studies indicate that owl limpets are highly susceptible to heavy human predation, which results in reduced mean shell sizes among Lottia populations along the coasts of Alta and Baja California. On San Miguel Island, we identified a significant trans-Holocene reduction in mean owl limpet size, beginning more than 6500 years ago and accelerating at least 4400 years ago. Fluctuations in limpet size show no clear correlation with changes in sea surface temperature and marine productivity, suggesting that increased predation by growing human populations was primarily responsible for the reduction in Lottia size over time. Our results provide further evidence that prehistoric peoples significantly influenced nearshore fisheries long before the development of the commercial and industrialized fisheries of historic times.  相似文献   
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