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Friedrich von Huene’s important scientific research on tetrapod fossils from Central Brazil has received little attention, even though it represents a significant contribution to early studies of vertebrate paleontology in the country including the first discoveries of dinosaur fossils in Brazil. von Huene described five reptile taxa in two papers published in important German scientific journals and used these specimens to make paleogeographic inferences regarding the Cretaceous of the Southern Hemisphere. von Huene warrants recognition as the first specialist to describe in detail the fossil reptile fauna of Central Brazil, which was made possible only by his network of contacts with important and influential naturalists of the cities of Rio de Janeiro and São Paulo.  相似文献   

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Alfred Russel Wallace The British naturalist Alfred Russel Wallace (1823–1913), well known as co‐discoverer of the “Darwinian” principle of natural selection, came from an ordinary background. Wallace left school aged 14 and never attended University. He became a land surveyor and studied, in his spare time, the works of the most famous naturalists of his age. After extensive expeditions (Amazon, 1848–1852; Southeast Asia, 1854–1862), Wallace spent the rest of his life in England as a free‐lance science writer. His contributions to systematics (he discovered/described many new species), evolutionary biology, zoogeography, anthropology and other branches of the live sciences are summarized in his 22 books and ca. 700 papers. Since Wallace became an adherent of spiritualism and mixed up supernatural phenomena with scientific facts in some of his later books, he remains a controversial figure in the history of the life sciences.  相似文献   

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Dr Chris Potten is a singularly influential figure in the field of epithelial biology. His contributions have been seminal and include the introduction of the epidermal proliferative unit and of the concept of epidermal stem cells. With around 400 scientific papers and reviews to his credit as well as two books, he has certainly made his mark. His contributions have been recognised by the award of the Curie medal and recently the Weiss medal for radiation biology. Dr. Potten graciously agreed to be interviewed for this Special Issue of The International Journal of Developmental Biology. This interview was conducted via e-mail during June -August 2003.  相似文献   

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Sterol molecule: structure, biosynthesis, and function.   总被引:7,自引:0,他引:7  
K Bloch 《Steroids》1992,57(8):378-383
This review briefly summarizes key researches on the structure of the sterol molecule from its very beginnings to the definitive elucidation in 1932. Cholesterol biosynthesis treated in somewhat greater detail covers the period from the 1930s to the 1960s. As a historic contribution, it presents researches previously published in numerous books, reviews, and original papers. The selection of topics, dictated by limits of time and space, is necessarily arbitrary and a personal choice. Readers of this journal will be familiar with the relevant chemical structures. Structural formulas are therefore omitted.  相似文献   

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Warren MA 《Bioethics》1987,1(2):189-198
Warren's book, Gendercide: The Implications of Sex Selection (Totowa, N.J.: Rowman and Allanheld; 1985), was reviewed by Helen Bequaert Holmes in the January 1987 issue of Bioethics. Here, Warren responds to the review by clarifying some of her moral arguments and continuing to defend the point of view that selecting the sex of children before conception or before birth is not always sexist, socially harmful, or disrespectful of the child as an end in itself.  相似文献   

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This article examines the study of natural history on the imperial periphery in late colonial Spanish America. It considers the problems that afflicted peripheral naturalists—lack of books, instruments, scholarly companionship, and skilled technicians. It discusses how these deprivations impacted upon their self-confidence and credibility as men of science and it examines the strategies adopted by peripheral naturalists to boost their scientific credibility. The article argues that Spanish American savants, deprived of the most up-to-date books and sophisticated instruments, emphasised instead their sustained experience of local nature and their familiarity with indigenous knowledge. It details how some creole naturalists, such as the Mexican José Antonio Alzate, questioned the applicability of European classificatory systems to American fauna and flora, and it analyses the complex relationship between natural science and creole patriotism.  相似文献   

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This study, with the purpose of summarizing the large aggregation of Food Plant Ethnobotany studies to find research history, current status and probable future trend, is based on the following questions: (1) What have been studied on traditional food plants previously? (2) What are studying on traditional food plants at present, and how? (3) What will be studied on traditional food plants in future? To conduct this survey, we searched for papers in Web of Science databases, using combinations of keywords, and the survey was limited to the studies published before June 30th, 2014. CITESPACE software was used to analyze the cited references of these papers. Nine hundreds and fifty four papers published from 1991 to 2014 were found. Analyzing these 954 papers and their cited references, we discovered that documentation of traditional food plants uses is the main study field in past and at present. Quantitative methods, dissemination of traditional knowledge, proper management of local plants resources, and nutritional and pharmaceutical components of food plants will be studied more in future. This paper will help to get a clue of Food Plant Ethnobotany.  相似文献   

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孙建财  刘任涛  王真  田颖 《生态学报》2024,44(14):6405-6415
放牧是草地管理和利用的主要方式,对草地生物多样性及其生态系统结构与功能产生深刻影响。土壤动物作为草地生态系统的重要组成部分,由于其生物生态学特性而使其分布受到放牧干扰的显著影响。然而,放牧如何影响土壤动物多样性尚缺乏系统总结与梳理。通过文献计量分析发现,关于放牧对土壤动物的影响研究论文中,美国发文最多(18.36%),其次是中国(16.39%),新西兰以12.14%的占比位居第三;国内外相关发文量经历了三个阶段:1999-2006年为起步发展阶段,2007-2013年为稳步发展阶段,2014年至今为快速发展阶段,国内外发文量分别在2021、2020年达到最高(15篇、81篇);相关论文的引用率逐年升高,2021年以3813次的引用率达到最高,说明放牧对土壤动物的影响研究引起了越来越多国内外学者的关注和重视。总结发现,放牧对土壤动物分布的影响主要以地上栖居和地下栖居土壤动物为研究对象,既包括直接作用途径,亦包括间接作用途径,而且作用方向取决于放牧强度和放牧方式。综合分析表明,以往的研究多注重于放牧对土壤动物产生的影响,忽视了放牧对土壤动物产生影响的作用途径的深入研究。根据我国草地资源分布特征及放牧对土壤动物的影响研究现状,提出未来我国在此领域研究的重点,为未来草地土壤动物多样性研究提供新思路。  相似文献   

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The review of the present status of limnological studies in India is based on Indian publications in Hydrobiologia since the inception of the Journal. About 325 Indian papers have appeared up to 1979; nearly two-third appeared in the last one decade. Ponds occupy first place among the freshwater bodies studied. There are only a few papers on the rivers and streams. The emphasis of studies on flora is generally on taxonomical and morphological aspects. Among the studies on fauna, several relate to different aspects of Crustacea, and taxonomy of rotifers. Fish studies published in Hydrobiologia do not reflect the trends of progress in India. Work on production, energy flow and functioning of ecosystems is limited. About thirty papers relate to estuarine and marine environments. Suggestions for future work are made in the light of present studies and the gaps.  相似文献   

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The lives and contributions of Ross and Joyce Bell are described with particular attention to studies of invertebrate natural history in the state of Vermont and carabid beetles of several groups, including the world rhysodine fauna. Their work, all done at the University of Vermont, was mainly taxonomic in nature and included aspects of the biology of the species considered. During their careers they described more than 75% of the c. 340 rhysodine species known to science. Ross Bell also wrote a number of seminal papers about the basal relationships of the Adephaga and the comparative anatomy of carabid coxal cavities. Ross and Joyce inspired several generations of students at UVM to take up advanced work in entomology and natural history.  相似文献   

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Kenya has a rich mammalian fauna. We reviewed recently published books and papers including the six volumes of Mammals of Africa to develop an up-to-date annotated checklist of all mammals recorded from Kenya. A total of 390 species have been identified in the country, including 106 species of rodents,104 species of bats, 63 species of even-toed ungulates(including whales and dolphins), 36 species of insectivores and carnivores, 19 species of primates,five species of elephant shrews, four species of hyraxes and odd-toed ungulates, three species of afrosoricids, pangolins, and hares, and one species of aardvark, elephant, sirenian and hedgehog. The number of species in this checklist is expected to increase with additional surveys and as the taxonomic status of small mammals(e.g., bats, shrews and rodents) becomes better understood.  相似文献   

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Allozyme and mitochondrial DNA variation were analysed to examine evolution of the nine species of springsnails (genus Tryonia) living in the Death Valley system (Owens and Amargosa basins) of southeastern California and southwestern Nevada. Both allozyme and mtDNA evidence indicate that this highly endemic fauna is non-monophyletic. Species from the upper Amargosa basin comprise a clade most closely related to snails living in the Colorado basin. Snails from the lower Amargosa basin (Death Valley trough) reflect a complex evolutionary history and two of these species are more closely related to an estuarine species from western California than to other snails of the region. These results indicate a commonality of pattern with the well-studied Death Valley pupfishes (Cyprinodon), which also are non-monophyletic and include species that are most closely related to Colorado basin congeners. These biogeographic patterns are interpreted within the context of a recently proposed model for the early history of the lower Colorado River.  相似文献   

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This paper reviews published knowledge on how to deal with invasive species during biological quality assessments in European river systems for water management and assessments of ecological quality required, for example, by the European Water Frame Work Directive. The papers studied included international papers and some standards for water assessment. An overview of the current state of neozoa research showed that many different topics are treated, comprising biogeography and fauna records, species replacements and effectiveness of colonisation, life cycles, competition between native and invasive species, habitat quality and pathways of migration. Additionally, some papers have been published recently on the integration of neozoa in index-based assessment systems. Although the decline or increase of alien species populations and the corresponding impacts on indigenous populations were frequently observed, the mechanisms behind the invasions often remain hypothetical. In the reviewed papers, issues such as possible reasons for coexistence, tolerances, quality of habitat or water, life history traits and introduction of diseases were rarely covered. Few neozoa are sufficiently investigated to be categorised as indicators. After discussing the advantages and disadvantages of inclusion or exclusion, inclusion of invaders in assessments of both biodiversity (all species) and human impact (only species classified in their specific tolerance) is suggested. Further research is required to (1) update and assign ecological profiles of the non-indigenous species currently and (2) assess the effects of new invaders on native communities.  相似文献   

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