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In biology, man is an object of research; therefore the question might be asked whether inspirations can go from biological data to the reflections on the mind-matter relation in man. The social aspect of man, as treated by sociobiology, is left out of consideration. The knowledge that man is mind, or has a mind, is no result of biological research. It is a datum from philosophy. The biologist, however, is living in a culture which knows about the mental character of man, and this is incorporated in his investigations. He knows that mental activities are connected with processes in the central nervous system and that, especially in the brain, localizations of mental activities are found. As a result of the split-brain experiments with patients and animals, some have arrived at the conclusion that there is a double consciousness. An approach from biology can lead to statements of a philosophical character, as, for example, statements about the unity, or even identity, of mind and matter. The theories of identity meet with great interest in scientific circles, and the truth value of identity statements is investigated. The system theory is taken into consideration. On a philosophical level a revaluation of the concept of matter can lead to a different sort of identity theory.  相似文献   

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As an essential and basic biological discipline, prokaryotic systematics is entering the era of genomics. This paradigmatic shift is significant not only for understanding molecular phylogeny at the whole genome level but also in revealing the genetic or epigenetic basis that accounts for the phenotypic criteria used to classify and identify species. These developments provide an opportunity and a challenge for systematists to reanalyze the molecular mechanisms underlying the taxonomic characteristics of prokaryotes by drawing the knowledge from studies of genomics and/or functional genomics employing platform technologies and related bioinformatics tools. It is expected that taxonomic books, such as Bergey’s Manual of Systematic Bacteriology may evolve into a systematics library indexed by phylogenomic information with an comprehensive understanding of prokaryotic speciation and associated increasing knowledge of biological phenomena.  相似文献   

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蜱螨的系统分类至今尚存在很多争议,尤其是目以上的分类地位很不统一。随着分子生物学技术在各个领域的渗透,结构生物学和发育生物学等领域的发展,人们对蜱螨的认识越来越深入。本文就蜱螨高级分类阶元中争论较大的几个方面做一讨论,主要包括蜱螨的分类基础、单源性问题、姐妹群及内部类群间的关系。  相似文献   

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Realist philosophies of science posit a dialectical relation between theoretical, explanatory knowledge and practical, including taxonomic knowledge. This paper examines the dialectic between the theory of descent and empirical, Linnaean taxonomy which is based on a logic of traditional classes. It considers the arguments of David Hull to the effect that many of the practical problems of empirical classification can be resolved by means of an ontology based upon the theory of descent in which species taxa are regarded as individuals rather than as classes or natural kinds.Contra Hull, it is argued that this view is, at best, only partially consistent with taxonomic practice and that it cannot sustain experimental practice which presupposes that species taxa be regarded as natural kinds. An outline is given of a possible alternative dialectic between a field theory of morphogenesis and a rational systematics involving a logic of relations.  相似文献   

7.
Under brief consideration is the problem of primary or secondary status of the judgments about taxa relative to the judgments about characters in the biological classifications. The following formal definition of taxonomic system (classification) TS is provided: TS = BT[T, C(t), R(t), R(c), R(tc)], where BT is a biological theory constituting content-wise background of the system, T is a set of taxa, C(t) is a set of taxonomic characters, R(t) is a set of relationships among taxa (similarity, kinship, etc.), R(c) is a set of relationships among characters (homology, etc.), and R(tc) is a set of correspondences among taxa and characters. The latter correspondences may be complete or incomplete. At ontological level, there two basical traditions exist in biological systematics regarding R(tc) according to which the biological diversity is patterned either as a set of groups of organisms (taxa) or as a set of their properties (characters). In the first case, taxon is "primary" relative to character (in cladistics); in its opposite, character is "primary" relative to taxon (in scholasticism, classical typology, classical phylogenetics). At epistemological level, incompleteness of the taxon-character correspondence makes classificatory procedure iterative and taxonomic diagnoses context-dependent. The interative nature of classificatory procedure makes the "primary" or "secondary" status of both taxa and characters relative and alternating. This makes it necessary to introduces a kind of uncertainty relation in biological systematics which means impossibility of simultaneous definition of both extensional and intentional parameters of the taxonomic system at each step of classificatory iterations.  相似文献   

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Sponges are an important source of secondary metabolites showing a great diversity of structures and biological activities. Secondary metabolites can display specificity on different taxonomic levels, from species to phylum, which can make them good taxonomic biomarkers. However, the knowledge available on the metabolome of non-model organisms is often poor. In this study, we demonstrate that sponge chemical diversity may be useful for fundamental issues in systematics or evolutionary biology, by using metabolic fingerprints as indicators of metabolomic diversity in order to assess interspecific relationships. The sponge clade Homoscleromorpha is particularly challenging because its chemistry has been little studied and its phylogeny is still debated. Identification at species level is often troublesome, especially for the highly diversified Oscarella genus which lacks the fundamental characters of sponge taxonomy. An HPLC–DAD–ELSD–MS metabolic fingerprinting approach was developed and applied to 10 Mediterranean Homoscleromorpha species as a rapid assessment of their chemical diversity. A first validation of our approach was to measure intraspecific variability, which was found significantly lower than interspecific variability obtained between two Oscarella sister-species. Interspecific relationships among Homoscleromorpha species were then inferred from the alignment of their metabolic fingerprints. The resulting classification is congruent with phylogenetic trees obtained for a DNA marker (mitochondrial COI) and demonstrates the existence of two distinct groups within Homoscleromorpha. Metabolic fingerprinting proves a useful complementary tool in sponge systematics. Our case study calls for a revision of Homoscleromorpha with further phylogenetic studies and identification of additional chemical synapomorphic characters.  相似文献   

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Systematics and taxonomy are essential: they respectively elucidate life's history, and organize and verify biological knowledge. This knowledge is built of interrelated concepts which are ultimately accounted for by biological specimens. Such knowledge is essential to decide how much and what biodiversity survives human onslaughts. The preservation of specimens in natural history collections is the essential part of the process which builds and maintains biological knowledge. These collections and the human expertise essential to interpret specimens are the taxonomic resources which maintain accurate and verifiable concepts of biological entities. Present and future knowledge of the complexities and diversity of the biosphere depends on the integrity of taxonomic resources, vet widespread ignorance and disregard for their fundamental value has created a global crisis. Preservation of specimens in natural history collections is chronically neglected and support to study and manage collections is very insufficient. The knowledge held by experienced taxonomists is not being passed on to younger recruits. Neglect of collections has destroyed countless specimens and threatens millions more. These threats to taxonomic resources not only impinge on systematics but all biology: this tragedy jeopardizes the integrity of biological knowledge. The consequences for environmental conservation and therefore humanity are also of dire severity and the biodiversity crisis adds unprecedented weight to the barely recognized crisis in taxonomy and systematics.Where correspondence should  相似文献   

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一般来讲,进化学派承认分支学派对系统学的研究作出了有意义的贡献,如应用分支分析方法重建系统发育,应用共有衍征确定分类群之间的分支关系以及应用外类群方法来判断性状的极性等,都对系统学的方法有所改进。但分支学派的致命缺点是拒绝接受并系类群。我们属于进化学派,认为并系类群是可以接受的。例如,根据分子资料分析,Zabelia属可以包括于Abelia属内。Zabelia属不但在花粉上和Abelia属不同,可能由于它占有了新的生态位,获得了新的特征,如叶柄基部膨大两两联合,并宿存以保护腋芽。有理由认为它们应独立成属,并不由于Zabelia属从Abelia属分出而使后者成为一个并系类群而把它们合并。分支学派的一些学者认为生物名称作为交流的工具和生物信息储存系统应有明晰的、唯一的和稳定的特性。但具等级的林奈命名系统并不具有这些特性来命名分支和种。最后,PhyloCode被提出。PhyloCode对分支的命名方法有3种,即分支结点定义、分支基干定义和衍征定义。我们认为林奈命名系统作为传媒系统在生物学界的应用已近250年,若要废弃它而采用PhyloCode,必然会在命名方面引起一片混乱。但我们并不是说PhyloCode的拥护者所提出的建议一无是处,我们建议他们宜继续进行研究。由于应用生物学种概念于植物界产生了许多问题,因此多为植物系统学家所抛弃。分支学派的兴起,推动了系统发育种概念的提出。该概念基于3个特征,即自征、区别特征和基本排它,因此分别命名为自征种概念、特征种概念和谱系种概念。事实上,目前大多数植物系统学家仍然应用着形态–地理学种概念,但我们在划分种时,必须有尽可能多的资料,特别是要将传粉、繁育系统、分子系统学资料和形态学资料结合起来。  相似文献   

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In this essay, three currently hotly debated issues in biological systematics, i.e., the paraphyletic group, the PhyloCode, and the phylogenetic species concept, have been briefly reviewed. (1) It is widely acknowledged that cladistics has made some positive contributions to the study of systematics. In particular, the employment of outgroup analysis for assessing character polarities, the application of synapomorphies to the inference of relationships between taxa, and the use of cladistic methods for reconstructing phylogeny, have all greatly facilitated the improvement of systematic approaches. A fatal flaw in cladistics is its refusal to accept paraphyletic groups. Frankly, we are adherents and practitioners of phyletics, and hence consider paraphyletic groups to be acceptable. For example, an AFLP analysis has shown that Zabelia (Caprifoliaceae) can be included in Abelia, but the members in Zabelia differ from those in Abelia not only in pollen morphology, but also in having persistent petioles dilated and connate at base, thus enclosing axillary buds, characters of adaptive significance obtained possibly when Zabelia members entered a new ecological niche, so we consider that they are better treated as two independent genera, though indeed such a treatment makes Abelia paraphyletic. (2) Some cladists pointed out that as the tool for communication and the system for information storage and retrieval, biological nomenclature is required to be unambiguous, unique and stable. They criticise the Linnaean rank-based system of nomenclature for failing to satisfy such requirements for the naming of clades and species. To address this problem, the PhyloCode is proposed in recent years, in which three definitions for clade naming are given, i.e., the node-based, the stem-based, and the apomorphy-based. We are of the opinion that since the Linnaean binominal system of botanical nomenclature has existed for nearly 250 years, the rejection of this system and the adoption of the PhyloCode would create a state of chaos in botanical nomenclature. This does not mean that there exist no merits in the proposals made by the PhyloCode supporters. We suggest that further studies should be conducted for its practical application. (3) It has been well known that there are many problems with the application of the biological species concept in plants, and thus at the present time the majority of plant systematists actually seldom use this concept in their practical work. The rapid development of cladistic approach has motivated the proposal of the phylogenetic species concept. This species concept is established based on three criteria, i.e., the autamorphy, the diagnosability and the basal exclusivity, hence the autamorphy species concept, the diagnosability species concept, and the genealogical concept are created respectively. Nevertheless, the morpho-geographical species concept is still predominantly adopted in plant systematics. When using this species concept, however, we should also take into account the data from other sources, particularly those from pollination biology, breeding system and molecular systematics.  相似文献   

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An attempt has been made to establish axiomatically the principles of biological classification. It is shown that if phylogenetic classification is based on the notion of dichotomous origin of new taxa implied in Hennig's theory of cladism then the outcome must be a hierarchy in the form of a dichotomous dendrogram. Since the rules of traditional classification do not lead to this type of "phylogenetic tree" it is concluded that the conventions of ordinary systematics do not permit the erection of a "natural system".  相似文献   

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杨亲二 《生物多样性》2016,24(9):1024-23
对洪德元先生最近在《生物多样性》(2016年第24卷第3期)发表的《关于提高物种划分合理性的意见》一文中的部分观点进行了进一步阐述。强调我国植物确实还存在大量种级水平的分类学问题有待解决, 我国植物分类学研究在一些重要发展阶段(如系统阶段和物种生物学阶段)上存在明显缺失, 需要弥补。指出分类学发展到今天, 不宜再强调“经典分类学”和“实验分类学”之分, 应采用多学科手段解决分类学问题; 我国应加强植物分类专著水平的研究工作, 注意培养年轻一辈植物分类学专著工作者; 在分类处理中应用居群概念和统计学方法时应特别谨慎; 在系统植物学中接受物种概念的多元性是必要的, 但要向达到广义的生物学种概念努力, 不宜以有所谓的“归并派”和“细分派”之分为借口而完全主观地划分物种。  相似文献   

14.
葡萄属野生资源在整个葡萄属(Vitis L.)的系统演化中占有十分重要的地位。葡萄属野生资源分布广泛,种间杂交容易,形态变异较为复杂,造成分类工作难度较大。长期以来,部分野生种的分类一直存在争议。本文从世界葡萄属植物的分类历史出发,对葡萄属野生种分类研究进展进行了综述。传统的分类方法不能够很好地解决不同种之间的亲缘关系,近十几年来,多种分子标记被应用于葡萄属的系统发育研究,并构建了葡萄属系统发育的基本框架。但是,分子系统学研究工作开展的远远不够,而且多数研究仍然受到资源的限制。未来建议加强葡萄属野生资源的收集和保护,并开展更全面的分类学修订工作。同时,充分利用分子系统学的相关技术手段,进一步阐明各野生种的分类地位。  相似文献   

15.
Compared with Hennig's phylogenetical systematics which has as its aim the retracing of genealogical relations between taxonomic groups, evolutionary morphological systematics is equally justified. Classifications of basic plans, morphological types, and morphofunctional systems of organisms serve as the foundation of evolutionary morphological systems. They are constructed on the basis of thorough understanding and further iteration of morphological transformation in phylogenetical branches based on the constructional pecularities of the morphofunctional systems. The evolutionary morphological approach in systematics is important especially for elaborating macrosystems dealing with vastly divergant groups where it is impossible to trace their real genealogy. The general principles of evolutionary morphological systematics are considered. A variant of the classification system of the Plathelminthes is suggested.  相似文献   

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SHORT NOTES     
Bock, W. 2000. Heuristics in systematics. Ostrich 71 (1 &; 2): 41–44.

Avian systematics is not only part of the science of ornithology, but serves heuristically as a foundation for many other analyses in ornithology. Systematics can be divided roughly into two major areas, namely species-level analyses and supraspecific classification. Of greatest significance is the distinction between provisional classifications and standard sequences, the latter are based on widely accepted classifications and have major useful functions such as the arrangement of taxa in handbooks, check-lists, and museum collections. The species concept is part of evolutionary theory, not systematics, and applies to contemporaneous groups of individual organisms. Clear distinctions separate the species concept, the species category, the species taxon, and the phyletic lineage—all usually designated as the “species”. The frequent practice of recognising all distinctive allopatric forms as separate species taxa results in two discrete classes of species taxa which largely destroys their usefulness for other biological analyses, including conservation efforts.  相似文献   

17.
The ability of the taxonomic community to heed Charles Godfray's wake‐up call to create ‘unitary’ taxonomic systems and make them available on the internet is hampered by real difficulties over achieving taxonomic consistency, and a cultural reluctance amongst systematists to embrace consensus. This paper explores these issues by examining the taxonomic history of an African milkweed butterfly, Amauris damocles sensu lato. Recent differences of opinion over the classification of this insect relate to fundamental differences in the theory and practice of systematics, from creationism through authoritarianism to cladistics, differences of a kind that will forever bedevil the distributed taxonomic system. If practical unitary schemes are to emerge, then the taxonomic community will need to adopt new ways of managing and recording taxonomic change, and develop a more responsible attitude towards the needs of others who are dependent of the primary products of systematics ‐names, and the classification schemes they symbolize.  相似文献   

18.
For ferns and lycophytes, the Neotropics is a hotspot of diversity (3000–4500 species), and second only to Southeastern Asia in richness and endemism. This paper presents the current state of knowledge on fern and lycophyte systematics in the Neotropics, and emphasizes sampling sufficiency and current taxonomic and phylogenetic knowledge. Plant systematics plays an important role in documenting diversity and geographic distribution patterns that are needed to understand relationships and evolutionary patterns, and a vital role in species conservation. Although in recent decades this field of science has undergone a revolution because of new approaches and techniques, data presented in this work shows that large gaps remain and there is still a long path towards fully understanding fern and lycophyte systematics in Neotropics. Approaches and how to choose areas that should be targeted in order to try to fulfill these knowledge gaps are discussed.  相似文献   

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The main purpose of the present review is to draw attention to growing problems in the modern systematics and phylogenetics which are presently underestimated by the professional community. The dramatic reduction of the importance of ontogeny and morphology in phylogenetic studies of the second part of the 20th century is considered among the major factors of the modern taxonomic and evolutionary paradigm. The deep contradiction of modern approaches, which either merely consider systematics and phylogeny as genealogy or even in a neotypolgical manner irrespective of the evolutionary idea, is demonstrated. Thus, despite the widespread opinion that the evolutionary theory is the major basis for taxonomy, the processes, which in fact caused the origin and formation of the systematic hierarchy are often considered as redundant for the procedure of classification. In this respect, the classical, but well forgotten statement that evolution is a modification of ontogeny is specially highlighted. Tight relationships between evolution, ontogeny, systematics, and phylogenetics are prima facie obvious, but also presently underestimated, although the field of the evo-devo is continuously growing. Paradoxically, even despite the outburst of various molecular ontogenetic approaches, the commonly accepted evolutionary paradigm still lacks a general theory for changes in the shape of organisms. As a step towards the development of such a theory, a synthesis (or more exactly, resynthesis) of still largely independently developing major biological fields, i.e., ontogenetic and evolutionary studies, on the one hand, and traditional taxonomy, on the other hand, a new concept of ontogenetic systematics is proposed. The new concept is intended for integration of supposedly ??immobile?? traditional taxonomy with the dynamics, but predominantly considered as hypothetical, evolutionary field based on the process of ontogeny, which, in contrast to the evolution itself, can be observed in the real time. Therefore, it is concluded that, for instance, the evolution of the main group of living organisms Metazoa, is primarily the evolution of a very limited number of ontogenetic cycles that were formed as early as the Early Cambrian. A significant underestimation of cyclic properties of ontogeny in the evolution and systematics is shown. Using two model groups, echinoderms of the class Ophiuroidea and dorid nudibranch mollusks (Gastropoda: Doridacea), practical importance of the integrative approach developed here is demonstrated. The ??disruption?? of the ancestral ontogenetic cycle and further formation of a new descendant cycle (which implies some continuity of ancestral and descendant characters) is considered to be a major evolutionary pattern. The model proposed implies either progressive (addition of stages and characters) or regressive (reduction of already existing stages and structures) modification of ancestral taxon, the diagnosis of which corresponds to the model of its ontogenetic cycle. In the extreme cases of disruption of the ancestral ontogenetic cycle, adult characters of descendants are substituted by juvenile ancestral features, demonstrating paedomorphoses in the narrow sense. Within the framework of the approach proposed, the evolutionary and ontogenetic models of ancestral ontogenetic cycles of brittle stars and dorid nudibranchs are developed and discussed. Based on the original material of the extinct Paleozoic ophiuroid group Oegophiurida, the origin of key evolutionary novelties is discussed. A major conclusion of the present review is the high necessity of integration of new molecular data with already well-established taxonomic hierarchy and ontogenetic information as a basis for the development of the general theory of transformations of organisms, i.e., the theory of evolution in its true sense.  相似文献   

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