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Jon M. Erlandson Todd J. Braje Torben C. Rick Nicholas P. Jew Douglas J. Kennett Nicole Dwyer Amira F. Ainis René L. Vellanoweth Jack Watts 《Journal of archaeological science》2011
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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Some researchers detected a new-found subsidiarity in rural policy after England’s 2001 Foot and Mouth Disease epidemic, with regional and sub-regional institutions working together to implement an economic recovery strategy. While such research began to link debates on the new regionalism and the rescaling of agro-food governance, its conception of the latter focused too narrowly on the ‘turn to quality’, thereby overlooking other important aspects of food relocalisation. Based on interviews conducted in England’s South West and West Midlands regions, this paper examines whether the attitudes of key actors from regional and sub-regional governance institutions provided a sound basis for partnership working on the food relocalisation policies recommended in the Government’s Strategy for Sustainable Farming and Food. It finds different attitudes on the part of regional and sub-regional actors, with the former favouring regional foods and the latter local foods. Despite scepticism from both groups about the ability of the England Rural Development Programme (2000–2006) to promote food relocalisation, grants were awarded to both regional and local food entrepreneurs, suggesting that the programme contributed more to food relocalisation than previously thought. 相似文献