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The theoretical concept of the biological species and the multidimensional species category, as currently applied by a majority of ornithologists and by many other biologists, replaced the typological-morphological species concept during the first half of this century and became a central tenet of the synthetic theory of evolution. The concept of biospecies is a 'horizontal' concept referring to contemporary reproductive communities at any particular period, e.g. the Recent period or any other time level of the geological past. Historical 'species' concepts as applied by cladists and palaeontologists refer to artificially delimited portions of 'vertical' phyletic lineages for which the application of the term 'species' causes severe problems. Discussions would be simplified if the concept and term 'species' was to be restricted to cross sections of phyletic lineages at any time level and a separate taxonomy outside the Linnaean system of genera and species was to be conceived to deal with phyletic lineages. Under each of the theoretical species concepts, species taxa are assigned broadly to intermediate or narrowly defined taxonomic species categories. Ornithologists of the 19th century applied morphological species concepts, emphasizing morphological character differences between species (rather than distinctness) and the fertility of con specific individuals (rather than the isolation from non-conspecific populations). Nearly all leading museum ornithologists in 19th-century Europe delineated monotypic Linnaean species, whereas the explorer-naturalists of the Gloger-Middendorff school (including Panas, Faber, Gloger, Nordmann, Middendorff, Schrenck, Radde, as well as Schlegel and Blasius) delimited widely circumscribed species taxa. Their researches in the vast territories of eastern Europe, Siberia and the Far East from the late 18th century to the 1880s and, in particular, their rich specimen material, demonstrated direct intergradation of many taxa (geographical varieties) of birds, thus revealing the conspecific nature of numerous narrowly conceived morphospecies previously described by museum workers. The ornithologists of the Gloger-Middendorff school also studied several conspicuous phenomena of geographical character variation in birds (and mammals) across Eurasia, especially plumage colouration (and pelage) and body size, but none of them was an evolutionist. They an adhered to a typological-creationist theoretical species concept. During the late 19th century, the museum specialists' taxonomic notion of narrow morphospecies dominated systematic ornithology in Europe, overtaking the work of the naturalists of the Gloger-Middendorff school, which fell into oblivion. The ornithologists of the Bairdian school in North America (Baird, Coues, Allen, Ridgway) further developed the concept of subspecies after the 1850s and especially from the 1870s onward. Their views were fully in accord with Darwin's theories of evolution' thus they defined the subspecies in a somewhat simplified manner as 'nascent species': These ornithologists were able to base their studies on collections of extensive specimen material which they had obtained during a series of exploring expeditions across the North American continent. Their studies led to the discovery of many aspects of both individual and geographic variation in birds. There are interesting historical similarities between the coinciding taxonomic interpretations and the comparable application of fairly broad limits of morphospecies by the North American ornithologists and the earlier exploring ornithologists in Europe, arrived at Independently by these, research groups, The study of specimens in 'series' (,suites'), beginninng with the naturalists of the Gloger-Middendorff school and, in particular, with the naturalists of the Bairdian school in North America, eventually led to the overcoming of the prevating typological view of variation and the development of 'population thinking'. Influenced by the work of Henry Seebohm in Britain and that of the North American ornithologists, Hartert in England and Kleinschmidt in Germany jointly succeeded in overcoming the strong opposition of the leadi.ng ornithologists in Europe during the 1890s and early 19008 and introduced a concept which soon developed into the biological species concept through the work of Stresemann, Rensch, and in particular, Ernst Mayr. Hopefully, ornithologists will continue the study of taxa at low, intermediate and high levels of microtaxonomic differentiation and will identify the subspecies groups, biological species and the biogeographical species in the world's avifaunas. Cladistic analyses will provide historical {'vertical'} overviews of phyletic lineages at different taxonomic levels.
Speakers of various Southern german dialects may be heard to use two syntactic variants of subordinate clauses which are represented by the following Swabian examples: (1) daß er den net will komme lasse (2) daß er den net komme lasse will Of these two variants of the three-element verbal complex, only the non-dialect counterpart of (2) is accepted as standard modern written German: (3) daß er ihn nicht kommen lassen will In earlier periods of the German language, however, both variants were used by authors of written texts.
Classical mutagenesis
(1992)
Classical genetic analyses require the presence of at least two different alleles per locus. Until the mid 1920's for the different alleles the investigators had to rely on spontaneous mutations. Since then mutagenic agents (mutagens) became available and these discoveries greatly enhanced the power of genetic analyses. Mutation is defined here as a heritable chemical alteration within the gene or the mutation process bringing about the change. Mutant is the individual (cell) containing the mutation. Point mutations are assumed to be free of loss, gain or rearrangement within the nucleotide sequence. Fonvard mutations are changes from the wild type allele (the allele predominant in wild populations) to a new allele, and the reverse process is backmutation. The frequency o/mutation per locus per generation (mutation rate) must be distinguished from mutant frequency, indicating simply the number of mutants in a population. Mutation in the broad sense involves also hereditary changes in chromosome number (polyploidy and aneuploidy) and chromosome structure, visible through the light microscope. The latter types are frequently called chromosomal aberrations. Arabidopsis, without further qualifications, in this context, will refer to Arabidopsis thaliana (L.) Heynh. in its diploid form (2n = 10). This species has three genomes, the nuclear, plastidic and the mitochondrial. Its nuclear genome (n = 5) is the smallest among higher plants (Leutweiler et al., 1984), containing about 0.7 - 1 x 108 bp, and redundancy is very low (Meyerowitz and Pruitt, 1985). The plastid genome is about the same size as that of the mcYority of higher plants, ca. 150 kb. The size of the mitochondrial genome is ca. 400 kb. Arabidopsis is an excellent tool for genetics and its critical features and known mutants have been reviewed (R&Iei , 1970, 1975a,b; Kranz, 1978; Meyerowitz and Pruitt, 1984; Meyerowitz, 1987, 1989; Estelle and Somerville, 1986; Bowman et al., 1988).
The study adressed 4 basic issues: (1) What are the substantive contents of human values? (2) Can we identify a comprehensive set of values? (3) To what extent is the meaning of particular values equivalent for different groups of people? (4) How are the relations among different values structured? These issues required resolution before the antecedents and consequences of value priorities, or cross-cultural differences in such priorities, could be studied effectively. Substantial progress has been made toward resolving each of these issues.
When in 1934, Robert BLEICHSTEINER published the Caucasian language specimina contained in the "travel book" of the 17th century Turkish writer Evliya Çelebi , he was struck by the amount of reliability he found in Evliya’s notations: "(Die Sprachproben) sind, von einzelnen Mißverständnissen abgesehen, und wenn man die falschen Punktierungen und Irrtümer der Kopisten abrechnet, außerordentlich gut, ja zuweilen mit einem gewissen phonetischen Geschick wiedergegeben, was der Auffassungsgabe und dem Eifer Evliyas ein hohes Zeugnis ausstellt. Man muß bedenken, wie schwer das arabische Alphabet, ohne weitere Unterscheidungszeichen, wie sie die islamischen Kaukasusvölker anwenden, die verwickelten, oft über 70 verschiedene Phoneme umfassenden Lautsysteme wiederzugeben imstande ist. Wenn trotzdem die Entzifferung der Sprachproben zum größten Teil geglückt ist, so muß man der ungewöhnlichen Begabung des türkischen Reisenden und Gelehrten schrankenlose Bewunderung zollen" (85). ...
The paper focuses on business negotiation in settings in which participants from different mothertongue backgrounds choose French, English andfor German as one of their languages of communication. A general scheme of the action-pattem of buying and selling will be sketched out which allows us to analyze specific Courses of verbal actions according ta their communicative functions within the negotiation process. In particular, the discourse of business communication is to be specified as a decision making process on the part of the buyer which is executed in a step-by-step order, and which is Open to the application of a bundle of the seller's strategies, tactics, and communicative techniques. In international negotiations, effects of unobserved miscommunication are, among others, far-stretched communicative circles, prolongation of negotiation time, non-functional explanations and several other repetitive structures. 1. Languages of trade and commerce - languages of communication 2. Communication in a Buy-Sell-Context is patterned 2.1. Entering the Pattern 2.2. The Main Phase 2.3. The Bidding Phase 2.4. The Specifc Conditions 2.5. Negotiating the Contract 3. The Central Point 3.1. The Buyer's Decision-Making Process 3.2 Decision-Making and Role-Playing 3.3. Intercultural Difference of the Decision-Making Process 4. Bridging the Buyer's Gap of Knowledge 5. The Language of Trade and Commerce 6. The Needs of Further Research: Data References
Crépin (1891) arranged 55 species of Rosa into 15 sections. Three of those sections contain taxa native to the British Isles, and members of several further sections have been reported as naturelized. In the discussion below, accepted names are shown in bold, while rejected names are given in italics.