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This paper analyzes the interaction between science, philosophy and politics (including ideology) in the early work of J. B. S. Haldane (from 1922 to 1937). This period is particularly important, not only because it is the period of Haldane's most significant biological work (both in biochemistry and genetics), but also because it is during this period that his philosophical and political views underwent their most significant transformation. His philosophical stance first changed from a radical organicism to a position far more compatible with mechanical materialism. The primary intellectual influence that was responsible for this shift was that of F. G. Hopkins. Later, Haldane came to accept Marxism and its official metaphysics, dialectical materialism, a move that let him accept the materialist conception of the world while still maintaining a resolute distance from mechanism. Throughout all these changes, what is most obvious is the influence of science on Haldane's philosophical views. An influence in the opposite direction is far less apparent.Parts of this paper are extracted from a longer work which concerns the interactions between philosophy and science throughout Haldane's scientific career (Sarkar forthcoming). The general conclusions reached here, from a consideration of Haldane's work only from 1922 to 1937 (see Section 6), remain the same for the rest of his life, as is detailed in the longer work. Thanks are due to R. S. Cohen, J. F. Crow, A. R. Fersht, J. Maynard Smith, R. C. Olby, D. Paul, M. Ruse, J. Stachel and S. Sturdy for helpful discussions and comments and criticism of the positions outlined in this paper. This is Contribution No. BTBG-92-4 from the Theoretical Biology Group, Boston University.  相似文献   

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R. Lespinasse 《Genetica》1985,66(2):151-151
Comment on the article ‘The B-chromosomes of Locusta migratoria I. Detection of negative correlation between mean chiasma frequency and the rate of accumulation of the B's; a reanalysis of the available data about the transmission of these B-chromosomes’ — Some critical remarks on the said article (published in Genetica 64: 155–164, 1984) are presented.  相似文献   

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During the late-glacial eruption of the Laacher See volcano 12,900 b.p. the whole area of the Neuwied Basin, middle Rhine region, was covered by several metres of the Laacher See Tephra (LST) damaging but also partly conserving the former vegetation. This gave the unique opportunity to study plant remains in situ and to estimate the spatial biodiversity of plant taxa within the area investigated at the end of the last glacial as if in a snapshot of 12,900 years ago. Different kinds of plant material can be found because of different preservation conditions namely imprints, charcoal and waterlogged remains. Investigations of this material from several places within the Neuwied Basin and the Brohl valley north of it allowed the reconstruction of the former vegetation at different scales from local to regional. This resulted in a large scale draft of a vegetation map of the studied area also based on the distribution and the stage of soil development at that time. As to whether thermophilous trees were already present is discussed but largely rejected. Electronic Supplementary Material Supplementary material is available for this article at  相似文献   

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Acknowledgments

We appreciate the invaluable contributions of the following reviewers during the editing of Vol. 8 Nos. 1–2.  相似文献   

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Summary The genus Calicophoron N?smark, 1937 is redefined. Only the following species originally assigned by N?smark to the genus are considered valid: C. calicophorum (Fischoeder, 1901) N?smark, 1937 (type species); C. papillosum (Stiles & Goldberger, 1910) N?smark, 1937; and C. raja N?smark, 1937. The following species previously assigned to the genus Paramphistomum Fischoeder, 1901 are considered valid but moved to the genus Calicophoron N?smark, 1937 in new combinations: C. bothriophoron (Braun, 1892); C. microbothrium (Fischoeder, 1901); C. papilligerum (Stiles & Goldberger, 1910); C. clavula (N?smark, 1937); C. microbothrioides (Price & McIntosh, 1944); C. sukari (Dinnik, 1954); C. phillerouxi (Dinnik, 1961); C. daubneyi (Dinnik, 1962) and C. sukumum (Dinnik, 1964). The genus Bothriophoron (Stiles & Goldberger, 1910) Grétillat 1958 is synoymized with Calicophoron N?smark, 1937. Paramphistomum crassum Stiles & Goldberger, 1910, P. cauliorchis Stiles & Goldberger, 1910, P. ijimai Fukui, 1922, P. (Cauliorchis) skrjabini Popova, 1937, P. erschovi Davydova, 1959, Calicophoron orientalis Mukherjee, 1966, C. wuchengense Wang, 1979 and Cotylophoron skrjabini Mitskevich, 1958 in part are considered synonyms of Calicophoron calicophorum (Fischoeder, 1901) N?smark, 1937. C. zhejiangense Wang, 1979 is regarded a synonym of C. papillosum (Stiles & Goldberger, 1910) N?smark, 1937. P. vangrembergeni Van Strydonck, 1970 and P. togolense Albaret, Bayssade-Dufour, Guilhon, Kulo & Picot, 1978 are considered synonyms of Calicophoron phillerouxi (Dinnik, 1961) n. comb. and Ceylonocotyle petrovi Davydova, 1961 is synonymized with Calicophoron microbothrioides (Price & McIntosh, 1944) n. comb. The species considered valid under the genus are redescribed and illustrated and scanning electron photomicrographs of the tegumental surfaces of some species are provided. A key to the species is given. Part of a thesis approved by the University of London for the award of the Ph.D. degree.  相似文献   

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The cyanogenic -glucosidase (linamarase) was purified from white clover leaf tissue. The enzyme is a homodimer with a molecular weight of 105 300–103 400 daltons estimated from molecular exclusion chromatography. The effect of buffer ions on the pH optimum and charge properties of the enzyme are presented. A combination of molecular exclusion chromatography and CM cellulose ion exchange chromatography purified linamarase 16 fold to a single 62 000 dalton polypeptide on SDS polyacrylamide gel electrophoresis. This polypeptide represented about 5% of the total soluble leaf protein and can be seen as a prominent band in SDS polyacrylamide gel electrophoresis of crude leaf extracts from Li Li plants. Screening backcross progeny showed that extracts from li li plants, which have no linamarase activity, lack this 62 000 dalton polypeptide. Linamarase is the major glycoprotein in white clover leaf extracts which binds to Concanavalin A-Sepharose.  相似文献   

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Breeding systems were evaluated for 51 plant species according to life form, pollination system, vegetation type, and phenology, in the coastal plain of Paraguaná Peninsula, Venezuela. Sexual systems were no associated to life form, pollination system, vegetation type, and phenology. The frequency distribution of sexual system was 82.3% hermaphroditism, 15.6% monoecy, and 1.9% dioecy. All sexual systems had a peak during the lowest rainfall. Genetic system distribution was 64.8% self-compatibility (including partially self-compatibility) and 35.2% self-incompatibility. Among self-compatible species, 45.1% were autogamous (19.6% not autogamous). The genetic systems were associated significantly to: (1) plant life form: self-compatible species tend to be herbaceous and self-incompatible plants tend to be woody species; (2) vegetation type: self-compatible species were predominant in the three vegetation types, but in the mangrove the frequency of self-compatible and self-incompatibles was similar; and (3) pollination system: most of the self-compatible species were polyphilous. Mating systems: xenogamous and autogamous species were associated only with plant life forms. Xenogamous plants were mostly woody species and autogamous plants were mostly herbaceous species. The high incidence of hermaphroditism, self-compatibility, and autogamy are related to herbaceous life form, polyphilous pollination system, and climatic conditions, together the insularity of the Paraguaná peninsula.  相似文献   

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Systematic Parasitology - Previous phylogenetic analyses of the Acanthocephala have demonstrated that the families Rhadinorhynchidae Lühe, 1912 and Transvenidae Pichelin & Cribb, 2001...  相似文献   

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This work presents a multiscale analysis of the fish diversity of the lower St. Lawrence River which flows from the Laurentian Great Lakes of North America. A database of about 14,000 fish sampling stations from the lower St. Lawrence is linked to five different habitat maps of the study area: hydrographical units, water masses, depth, sediment type and wetland type. We hypothesize that species turnover (beta diversity) will be significant among these habitat maps. For each map, we calculate a UPGMA dendrogram based on the Jaccard coefficient of similarity in species occurrences as a first assemblage–habitat model. A randomization test is then used to identify the significant dendrograms from which we infer fish assemblages. We then show that many species are actually selecting or avoiding habitats. Finally, species selecting particular habitats are described by some selected ecological traits that are expected to occur frequently in those habitats. We found assemblages for the hydrographical units but not for the water masses. The fluvial section is selected by many stenohaline and some euryhaline species, while the freshwater estuary and the brackish estuary are only selected by euryhaline species. In the fluvial section at the hydrographical unit scale, many species associated with lentic habitats are limnophilic and more vegetation-dependent while many species selecting lotic habitats are rheophilic insectivorous species. Significant assemblages are defined for depth, sediment type and wetland type. Taken together, we found strong empirical evidence of a diverse actively selecting littoral assemblage of small, low mobility fishes opposing a channel assemblage of larger, more mobile fishes.  相似文献   

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