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The Problem of Disciplines/The Discipline of Problems   总被引:1,自引:0,他引:1  
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The successful conservation of biodiversity depends in part upon an accurate assessment of the diversity to be preserved. This assessment is in the domain of systematics, taxonomy, and general comparative biology. Specimens play a central role in this science, and research collections thus represent the touchstone of biodiversity. The massive job of describing and understanding avian diversity is far from complete, yet the specimen basis for much-needed work is not being added to our collections; current holdings are inadequate. The dwindling influx of specimens is due primarily to opposition to collecting, which is fueled by (1) focusing conservation at the level of the individual; (2) unfamiliarity with population biology; (3) misunderstanding of scientific research; (4) typological thinking; and (5) misplaced morality. Specimen-based avian research has a long and scientifically strong history, and the benefits of this research have been extensive. Our research collections must serve as functional biological libraries. The majority of avian populations can easily withstand the relatively tiny levels of collecting required to keep this science vigorous. Insofar as avian conservation necessarily includes the preservation of a myriad of species comprising the ecosystems upon which birds rely, this problem has broad implications for the conservation of biodiversity.  相似文献   

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The traditional theory of exhaustion is revised to allow for long run capital mobility. This model is extended to include the impact of cumulative environmental damages on the optimal path of resource use. Models and optimal markets are then analyzed for cases where minerals are available over a continuum of quality and where recycling ameliorates inevitable exhaustion of non-renewable resources. Finally, the impact of technological change on long run trends in mineral prices is examined.  相似文献   

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The recent extnction of the Caribbean monk seal Monachus tropicalis has been considered an example of a human‐caused extinction in the marine environment, and this species was considered a driver of the changes that have occurred in the structure of Caribbean coral reef ecosystems since colonial times. I searched archaeological records, historical data, and geographic names (used as a proxy of the presence of seals) and evaluated the use and quality of these data to conclude that since prehistoric times the Caribbean monk seal was always rare and vulnerable to human predation. This finding supports the hypothesis that in AD 1500, the Caribbean monk seal persisted as a small fragmented population in which individuals were confined to small keys, banks, or isolated islands in the Gulf of Mexico and the Caribbean Sea. This hypothesis is contrary to the assumption that the species was widespread and abundant historically. The theory that the main driver of monk seal extinction was harvesting for its oil for use in the sugar cane industry of Jamaica during the 18th century is based primarily on anecdotal information and is overemphasized in the literature. An analysis of reported human encounters with this species indicates monk seal harvest was an occasional activity, rather than an ongoing enterprise. Nevertheless, given the rarity of this species and its restricted distribution, even small levels of hunting or specimen collecting must have contributed to its extinction, which was confirmed in the mid‐20th century. Some sources had been overlooked or only partially reviewed, others misinterpreted, and a considerable amount of anecdotal information had been uncritically used. Critical examination of archaeological and historical records is required to infer accurate estimations of the historical abundance of a species. In reconstructing the past to address the shifting baseline syndrome, it is important to avoid selecting evidence to confirm modern prejudices. Puntos de Referencia Cambiantes y la Extinción de la Foca Monje Caribeña  相似文献   

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The Popularity of Biodiversity   总被引:1,自引:0,他引:1  
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The Psychology of Survival   总被引:1,自引:0,他引:1  
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The Politics of Carbon   总被引:1,自引:0,他引:1  
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