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1.
The purpose of this review is to provide a global perspective on Oncorhynchus salmonine introductions and put-and-take fisheries based on modern stocking programs, with special emphasis on freshwater
ecosystems. We survey the global introductions of nine selected salmonines of the genus Oncorhynchus: golden trout, cutthroat trout, pink salmon, chum salmon, coho salmon, masu/cherry salmon, rainbow trout/steelhead, sockeye
salmon/kokanee, and chinook salmon. The information is organized on a geographical basis by continent, and then by species
and chronology. Two different objectives and associated definitions of ‘success’ for introductions are distinguished: (a)
seed introduction: release of individuals with the purpose of creating a wild-reproducing, self-sustaining population; and
(b) put-and-take introduction: release of individuals with the purpose of maintaining some level of wild population abundance,
regardless of wild reproduction. We identify four major phenomena regarding global salmonine introductions: (1) general inadequacy
of documentation regarding introductions; (2) a fundamental disconnect between management actions and ecological consequences
of introductions; (3) the importance of global climate change on success of previous and future introductions; and (4) the
significance of aquaculture as a key uncertainty in accidental introductions. We conclude this review with a recognition of
the need to terminate ongoing stocking programs for introduced salmonines worldwide. 相似文献
2.
3.
Colonial Williamsburg, and U.S. history museums generally, claim to transform public history into collective memory. That is, they convey an objective documented history to the public who, absorbing that history, acquires an appropriate collective or national memory. We argue that the emphasis on consumer (visitor) experience at such museums collapses the distance between the reconstructed past (the museum's history lesson) and the visitor's touristic or familial experience at the site. Visitors indeed remember their visits to Colonial Williamsburg, but their specific memories would seem to have little to contribute to any 'collective memory' of a 'national history.' 相似文献
4.
The past, present and future of childhood malaria mortality in Africa 总被引:11,自引:0,他引:11
During the past few years, there has been a historic series of declarations of renewed commitment to malaria control in Africa. Whether the burden of malaria is increasing in Africa is a moot point. This article attempts to re-construct the evidence for the trends in childhood mortality as a result of Plasmodium falciparum infection over the last century in Africa. 相似文献
5.
Anita Herle 《Ethnos》2013,78(2):253-274
Preparations for a centenary exhibition to mark the 1898 Cambridge Anthropological Expedition to the Torres Strait incorporated cross-cultural collaborative work, reflecting the changing roles of museums as sites for contact and research combining curatorial expertise and indigenous knowledge. Specific objects in the collections of the University of Cambridge Museum of Archaeology and Anthropology continue to be active intermediaries in the relationship between museum staff and Torres Strait Islanders and the museum itself has become an important field site. This paper provides an ethnography of the process of creating the exhibition and explores different ways that many of the objects displayed have resonance for Islanders today. 相似文献
6.
《Journal of biological education》2012,46(3):172-174
Analogies between plants and animals are often a source of confusion in the understanding of sexual reproduction in green plants The ancient view that plants are non-sexual because they hold a place below animals on the ladder of nature was still held by many scientists in the 1 8th century. Paradoxically, al this time, Linnaeus and others were also postulating the universality of plant sexuality by using analogies with animals to over-extend the slowly emerging experimental evidence about the functions of floral parts. Today's school leavers seem to have similarly diverse views. A lack of school focus on gamete fusion appears to result in a continuing reliance on analogies with animals, and a belief that plants undergo only a qualified version of sexual reproduction. Suggestions for classroom activities to overcome this are offered, and some wider implications are considered. 相似文献
7.
P. M. Brakefield F. Kesbeke 《Proceedings. Biological sciences / The Royal Society》1997,264(1382):717-723
Experiments on life history genetics are usually performed using constant temperature environments in the laboratory. However, the dynamics of insect growth can be influenced profoundly by daily fluctuations in temperature such as those which characterize field environments. We report here on experiments using different stocks and selected lines of a tropical butterfly, Bicyclus anynana, to examine whether genotype-environment interactions occur for three traits describing pre-adult growth. These traits were measured over two pairs of environments differing in mean temperature, each of which had a constant, and a cycling temperature regime. Development time, pupal weight and growth rate show genotype-environment interactions, especially at comparatively low average temperatures. Researchers should, therefore, take care when extrapolating from the form of genetic covariance matrices and ''trade-offs'' among life history traits found in constant temperature environments to those likely to occur in nature. <br> 相似文献
8.
Une médecine du fonds des âges : trépanations,amputations et tatouages thérapeutiques au Néolithique
《L'Anthropologie》2015,119(1):58-71
The first shepherds and peasants of the European Neolithic period, between VIth century and IIth millennium BC, had acquired serious medical knowledge. The cranial trepanations and the amputation of members accomplished successfully testify perfectly controlled surgical techniques, which indicate a transmissible knowledge. Tattoos towards a therapeutic end reveal however that the medicine of this time still remained under the influence of rituals and magic. 相似文献
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10.
The dark ocean and the underlying deep seafloor together represent the largest environment on this planet, comprising about 80% of the oceanic volume and covering more than two-thirds of the Earth's surface, as well as hosting a major part of the total biosphere. Emerging evidence suggests that these vast pelagic and benthic habitats play a major role in ocean biogeochemistry and represent an “untapped reservoir” of high genetic and metabolic microbial diversity. Due to its huge volume, the water column of the dark ocean is the largest reservoir of organic carbon in the biosphere and likely plays a major role in the global carbon budget. The dark ocean and the seafloor beneath it are also home to a largely enigmatic food web comprising little-known and sometimes spectacular organisms, mainly prokaryotes and protists. This review considers the globally important role of pelagic and benthic protists across all protistan size classes in the deep-sea realm, with a focus on their taxonomy, diversity, and physiological properties, including their role in deep microbial food webs. We argue that, given the important contribution that protists must make to deep-sea biodiversity and ecosystem processes, they should not be overlooked in biological studies of the deep ocean. 相似文献