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1.
The problems are discussed related to development of concepts of rational taxonomy and rational classifications (taxonomic systems) in biology. Rational taxonomy is based on the assumption that the key characteristic of rationality is deductive inference of certain partial judgments about reality under study from other judgments taken as more general and a priory true. Respectively, two forms of rationality are discriminated--ontological and epistemological ones. The former implies inference of classifications properties from general (essential) properties of the reality being investigated. The latter implies inference of the partial rules of judgments about classifications from more general (formal) rules. The following principal concepts of ontologically rational biological taxonomy are considered: "crystallographic" approach, inference of the orderliness of organismal diversity from general laws of Nature, inference of the above orderliness from the orderliness of ontogenetic development programs, based on the concept of natural kind and Cassirer's series theory, based on the systemic concept, based on the idea of periodic systems. Various concepts of ontologically rational taxonomy can be generalized by an idea of the causal taxonomy, according to which any biologically sound classification is founded on a contentwise model of biological diversity that includes explicit indication of general causes responsible for that diversity. It is asserted that each category of general causation and respective background model may serve as a basis for a particular ontologically rational taxonomy as a distinctive research program. Concepts of epistemologically rational taxonomy and classifications (taxonomic systems) can be interpreted in terms of application of certain epistemological criteria of substantiation of scientific status of taxonomy in general and of taxonomic systems in particular. These concepts include: consideration of taxonomy consistency from the standpoint of inductive and hypothetico-deductive argumentation schemes and such fundamental criteria of classifications naturalness as their prognostic capabilities; foundation of a theory of "general taxonomy" as a "general logic", including elements of the axiomatic method. The latter concept constitutes a core of the program of general classiology; it is inconsistent due to absence of anything like "general logic". It is asserted that elaboration of a theory of taxonomy as a biological discipline based on the formal principles of epistemological rationality is not feasible. Instead, it is to be elaborated as ontologically rational one based on biologically sound metatheories about biological diversity causes.  相似文献   

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生物分类是生物学领域最基础的研究工作,生物多样性是当前生命科学研究热点之一。概述了生物分类思想的历史发展,探讨了基因组多样性研究中的伦理问题。  相似文献   

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Polar Biology - The Bellingshausen and Amundsen Seas are among the least studied Antarctic areas. Pycnogonids constitute a common and conspicuous component of the Antarctic marine fauna. Antarctic...  相似文献   

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Mycorrhiza management in forestry must be predicated on an understanding of fungal biology and ecology. A fundamental building block of the biology and ecology of any organism is accurate identification and an understanding of its relationship to other organisms. The taxonomy of the larger fungi has been largely based on morphological classification of sexual structures but now Taxonomy routinely incorporates mating studies, and biochemical and molecular data. Taxonomy may not revolutionize theories on mycorrhiza but can clarify some of the inconsistencies due to misrepresentation or over-generalizations and inappropriate conclusions drawn from studies with inaccurately identified fungi. To illustrate this, we discuss and example where incorrect fungal names were repeatedly erroneously applied in morphological and physiological research reports on this fungus, e.g. Laccaria laccata. In this case subsequent taxonomic study revealed the reason for the conflicting research results reported for this fungus. We discuss the status of identifying the ectomycorrhizal fungi in various forest communities in Australia and the relationships of this process to assessing their use in forestry. Recent intensive efforts to collect, isolate and identify Australian ectomycorrhizal fungi have revealed an enormous and unique species diversity, e.g., for truffle-like fungi, over 2000 collections from the last five years alone have yielded 2 new families, 24 new genera, and about 184 new species. Nearly 95% of the described and undescribed fungi from Australia are novel, with some 22 genera and 3 families endemic. In most cases the current systematic knowledge of mycorrhizal fungi is inadequate to support clear framework for Australian taxa. This reflects the traditional Northern Hemisphere view of the world, the uniqueness of the Australian fungal flora, and how poorly it is known. For example, the genus Hymenogaster had been widely acknowledged as the most reduced member of the Cortinariaceae. However recent work on Hymenogaster species from the Southern Hemisphere has offered a number of alternative affinities to various species. We also discuss the role proper identification of the organisms involved plays in understanding the ecosystem. Emphasis should be placed on how species diversity equates with physiological and genetic diversity and how a sound taxonomic understanding of species and their systematic position is essential to properly manage them. Accurate taxonomic information will continue to be required as the basis for assessing the role of ectomycorrhizal fungi in sustained ecological development. Of particular significance is the role of ectomycorrhizal fungi in maintenance of plant diversity in natural ecosystems and those disturbed by management. In conclusion, we present some key research areas involving the use of taxonomy that need priority attention.  相似文献   

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The RUBICODE project draws on expertise from a range of disciplines to develop and integrate frameworks for assessing the impacts of environmental change on ecosystem service provision, and for rationalising biodiversity conservation in that light. With such diverse expertise and concepts involved, interested parties will not be familiar with all the key terminology. This paper defines the terms as used within the project and, where useful, discusses some reasoning behind the definitions. Terms are grouped by concept rather than being listed alphabetically.  相似文献   

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The biodiversity of cyanobacteria is paradoxical since these bacteria vary in cytological characters although are metabolically uniform. Cyanobacterial phylogeny is also paradoxical as the structural genes of rRNA are too conservative for a large phylum. On the paradoxical evolutionary tree, neighbors have strongly contrasting phenotypes, while objects with similar phenotypes demonstrate a heterological structure of 16S rDNA. The systematics of cyanobacteria is paradoxical, too, since it is logically contradictory: on the one hand, phylum BX Cyanobacteria generally is separated on molecular-biological grounds. On the other hand, in accordance with the traditional botanical algorithm used in classification of blue-green algae, this phylum is artificially subdivided into morphological groups (ultrastructural characters are taken into account only in rare cases). A unique trait of the taxonomy of cyanobacteria (with rare exceptions, e.g., Cyanobacterium stanieri) is its general nonusage of the category of species. The species epithet is replaced by a stain index (e.g., Anabaena PCC 7122).  相似文献   

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A comparative ultrastructural study was made of both thin- and thick-walled oocysts of Cryptosporidium parvum. According to the authors' findings, all the oocysts in C. parvum should be considered as thin-walled, since their walls have been composed of a single membrane or of two, closely apposed membranes without any additional substance in between. Despite the presence of two types of wall-forming bodies (WFB) in the maturing macrogamete or zygote, there is no evidence of their involvement in oocyst wall formation. In this concern, the function and destiny of WFB in C. parvum oocysts still remain obscure. Similar structure of the oocysts wall was reported elsewhere for thin-walled oocysts of fish coccidia of the genera Goussia and Eimeria. In C. parvum, the "thick-walled" oocysts differ from oocysts with thin walls in the availability in the former of a single sporocyst. The sporocyst wall consists of two unequal layers: a thin outer layer and a thicker inner one, in which a characteristic suture line is occasionally seen. By this feature the thick-walled oocysts of C. parvum bear similarities with oocysts of the cyst-forming coccidia (Cystoisospora, Toxoplasma, Sarcocystis) and of the genus Goussia: in all these the valves making up the sporocyst wall are joint just along the suture line. The literary and the authors' own data make it possible to suppose that the suture detected in C. parvum oocysts is located in the sporocyst wall, joining its valves, rather than in the oocyst wall proper, known to be composed of one or two, closely apposed unit membranes. Again, the availability of a suture (or sutures) in the sporocyst hardly provides enough reason to relate C. parvum with either cyst-forming, or fish coccidia, since this structure itself may be of a convergency character, rather than of systematic value. This may be substantiated, at least in part, by the authors' previous findings (Beyer, Sidorenko, 1984) of a similar structure, originally referred to as a "slit channel", in the intraerythrocytic capsule around gamont stage of haemogregarines--the adeleid coccidia of the genus Karyolysus. The suture-like structure could have originated in the evolution independently in different groups of parasitic protozoa to serve eventually as a suitable mechanism for immediate separation of elements involved in protective formation harbouring different developmental stages, including, for example, sporozoites in the eimeriid coccidia, or gamonts in the adeleid coccidia.  相似文献   

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The ideas of wholeness of superorganism units consist of three constituents: 1) emergeness of properties of the whole; 2) structureness; 3) separability of the whole. Emergeness is a character of both integrated and complex units. Integrated units in strict sense are those that consist of functionally different parts. Species but not super-specific taxa are integrated units. The ideas of unity are based on formula "unity is an aggregation of shape and matter". In taxonomy the idea of archaetype can be used as a shape. Superspecific taxa but not species are recognized as unitary units in taxonomy. Unitary but not integrated units can be considered as individuals.  相似文献   

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Ixodid ticks are recognized world-wide as major vectors of arboviruses, rickettsiae, spirochaetes and parasitic protozoa of man and domestic animals. Some ticks also inject a debilitating, sometimes fatal, paralytic toxin in their saliva. All these factors are transmitted via the salivary glands and mouthparts of the feeding tick. Tick feeding is a prolonged and complex process. Major developmental events occurring within the tick during feeding, as well as extensive tick-host interactions, all influence the likelihood of pathogen transmission. In this review, Reuben Kaufman discusses the sequence and complexity of these interactions.  相似文献   

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The species problem, despite decades of heated debates, has not been resolved yet. Recently, two new species concepts have been published, the mitonuclear compatibility species concept and the inclusive species concept. I briefly discuss them, together with a recent attempt at standardizing taxonomic decisions, in the broader framework of what I believe is an inherent limitation of taxonomy—imposing a discrete system on a continuous process (evolution) that leads to fuzzy boundaries in nature. In the light of this, taxonomists, biologists in general and conservationists alike will have to accept the fact that completely nonarbitrary species delimitation is impossible. This has serious ramifications in all disciplines that rely on species, and particularly species counts, as a basic currency for quantitative analyses (ecology, evolutionary biology) and practical decision-making (conservation and environmental policy).  相似文献   

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M Zaider 《Radiation research》1990,123(3):257-262
This paper reviews general concepts for understanding the effects of two or more agents. Models describing exposures to mixed fields of radiation are developed on the basis of very general postulates, and some of their consequences are examined against a set of experimental data.  相似文献   

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Gibson S 《Bioethics》2004,18(3):221-233
When one thinks about the ethics of abortion, one inevitably thinks about rights, since it is in terms of the concept of rights that much of the debate has been conducted. This is true of overtly feminist as well as non-feminist accounts. Indeed, some early feminist writers--Judith Jarvis Thomson and Mary Ann Warren, for example--employ a model of rights that is indistinguishable, or virtually indistinguishable, from that of their non-feminist counterparts. However, more recent feminist writers have developed a different understanding of 'a woman's right to choose.' In this paper, I will begin by outlining the non-feminist debate over the moral permissibility of abortion. I will suggest that this debate is irresolvable, since at its heart is an 'essentially contested concept', that of personhood. I will then consider the way in which some feminist writers have attempted to reconceive the terms of the abortion debate and suggest an expanded account of women's right to abortion, drawing on the work of Susan Sherwin. Finally, I will argue that there is a further element to a 'woman's right to choose' that expands on and provides a conceptual link between feminist and non-feminist understanding of abortion.  相似文献   

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