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Systematic Relationships (systematic + relationships)
Selected AbstractsOrigin and Evolution of the Lichenized Ascomycete Order Lichinales: Monophyly and Systematic Relationships Inferred from Ascus, Fruiting Body and SSU rDNA EvolutionPLANT BIOLOGY, Issue 2 2001M. Schultz Abstract: The Lichinales are a group of lichenized ascomycetes that almost exclusively possess cyanobacteria as their primary photobiont and are hitherto separated from the Lecanorales, the major group of lichenized ascomycetes, by thallus structure, ascoma ontogeny, ascus structure and ascus function. The relationship of the two families Peltulaceae and Lichinaceae, both placed within the Lichinales, with the Heppiaceae, placed within the Lecanorales, was investigated, as well as a possible sister group relationship of the Lichinales to the Lecanorales. Phylogenetic analyses included non-molecular data as well as 18S rDNA sequence data. The monophyly of the Lichinales including the family Heppiaceae and a sister group relationship of Lichinales and Lecanorales, based on the shared presence of lecanoralean asci, are proposed in a morphological hypothesis. Parsimony and distance analyses of 18S rDNA sequence data strongly support the monophyly of the Lichinales, including all three families. Therefore, the presence of rostrate, lecanoralean asci in Peltula and part of the Lichinaceae suggests that this ascus type is an autapomorphy of the monophyletic Lichinales. Furthermore, the occurrence of prototunicate asci in the Heppiaceae and most of the Lichinaceae is autapomorphic and was gained independently by reduction of the rostrate ascus. The 18S rDNA analysis did not reject the non-molecular hypothesis of a sister group relationship of the Lichinales and the Lecanorales as based on ascus characters. The alternative placement of the Lichinales as the sister group of all inoperculate euascomycetes excluding the Sordariomycetes and most of the Leotiales in the gene tree received unsufficient bootstrap support and no support from any non-molecular data and consequently was rejected. [source] The Thrips orientalis group from South-east Asia and Australia: some species identities and relationships (Thysanoptera, Thripidae)AUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 4 2005Laurence A Mound Abstract, A thrips associated in Thailand with the flowers of Paederia foetida, a rubiaceous weed in Florida that is a threat to Australia, is here recognised as Thrips morindae Priesner, a species previously considered a synonym of T. javanicus Priesner. Systematic relationships of these species with others in South-east Asia and the Australasian region are discussed. Two new species-groups are designated: the T. obscuratus group of six species from New Zealand and New Caledonia, and the T. orientalis group of 12 South-east Asian species that are associated with scented white flowers such as Gardenia. Four species of this second group are recorded from tropical Australia. [source] Systematics and Biogeography of Hard Ticks, a Total Evidence ApproachCLADISTICS, Issue 1 2000J.S.H. Klompen Systematic relationships among the basal Ixodidae are examined using one morphological and three molecular data sets, 18S and 28S nuclear and 16S mitochondrial rDNA. Although different combinations of partitions are incompatible in a partition homogeneity test, combining them produces similar or better support for most major lineages through both additive and complementary effects. The different data sets are not complete for all taxa, but inclusion or exclusion of taxa with missing data for one or more data sets (8 of 29 ingroup taxa) does not influence overall tree topology and only weakly affects support levels. The only notable effect was based on gap treatment in the 28S data set. Gap treatment completely changes the arrangement and support levels for one basal node. The combined analyses show strong support for the Metastriata, a lineage including most endemic Australian Ixodes, and a lineage including the remaining Ixodes, but not for the Prostriata (=Ixodes s.l.). The distribution pattern of endemic Australian taxa (nearly all included in three exclusively Australian basal lineages) suggests that these lineages, and by extension the Ixodidae, originated after the isolation of Australia in the late Cretaceous, much more recently than previously indicated. [source] Secotioid Agaricales (Basidiomycetes) from MongoliaFEDDES REPERTORIUM, Issue 3-4 2007H. Dörfelt PD Dr. A recapitulation of all findings of Mongolian secotioid Agaricales is given. Four species are known: Montagnea arenaria, Montagnea haussknechtii, Endoptychum agaricoides and Gyrophragmium dunalii. Two out of them, M. haussknechtii and E. agaricoides, are reported for the first time in Mongolia. An overview of distribution and systematic relationships of the taxa is given. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) Secotioide Agaricales (Basidiomycetes) aus der Mongolei Es werden alle Funde secotioider Agaricales aus der Mongolei rekapituliert. Vier Arten sind bekannt: Montagnea arenaria, Montagnea haussknechtii, Endoptychum agaricoides und Gyrophragmium dunalii. Zwei von ihnen, M. haussknechtii und E. agaricoides, werden erstmals für die Mongolei erwähnt. Es wird ein Überblick über die Verbreitung und die systematischen Beziehungen der Taxa gegeben. [source] Educational Federalism in Germany: Foundations of Social Inequality in EducationGOVERNANCE, Issue 1 2009MARKUS FREITAG This article applies Fuzzy Set Qualitative Comparative Analysis to examine how sub-national education systems affect the extent of social inequality in education within the German federal states. Variations in educational outcomes between the federal states can be primarily attributed to the strict educational decentralization in Germany. We examine four conditions of regional education systems presumed to be relevant for the extent of social inequality in education: the availability of early childhood education, the development of all-day schools, the onset of tracking to different school types, and the degree of tripartition in secondary education. Altogether, we find systematic relationships between the variation of sub-national education systems and the extent of social inequality in education. The results indicate that well-developed early childhood education is necessary for a low degree of educational inequality. However, educational inequality is not directly related to partisan and socioeconomic determinants. [source] What determines the value of life? a meta-analysisJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 2 2002Janusz R. Mrozek A large literature has developed in which labor market contracts are used to estimate the value of a statistical life (VSL). Reported estimates of the VSL vary substantially, from less than $100,000 to more than $25 million. This research uses meta-analysis to quantitatively assess the VSL literature. Results from existing studies are pooled to identify the systematic relationships between VSL estimates and each study's particular features, such as the sample composition and research methods. This meta-analysis suggests that a VSL range of approximately $1.5 million to $2.5 million (in 1998 dollars) is what can be reasonably inferred from past labor-market studies when "best practice" assumptions are invoked. This range is considerably below many previous qualitative reviews of this literature. © 2002 by the Association for Public Policy Analysis and Management. [source] Systematic positions of Lamiophlomis and Paraphlomis (Lamiaceae) based on nuclear and chloroplast sequencesJOURNAL OF SYSTEMATICS EVOLUTION, Issue 6 2009Yue-Zhi PAN Abstract, Genera Lamiophlomis and Paraphlomis were originally separated from genus Phlomis s.l. on the basis of particular morphological characteristics. However, their relationship was highly contentious, as evidenced by the literature. In the present paper, the systematic positions of Lamiophlomis, Paraphlomis, and their related genera were assessed based on nuclear internal transcribed spacer (ITS) and chloroplast rpl16 and trnL-F sequence data using maximum parsimony (MP) and Bayesian methods. In total, 24 species representing six genera of the ingroup and outgroup were sampled. Analyses of both separate and combined sequence data were conducted to resolve the systematic relationships of these genera. The results reveal that Lamiophlomis is nested within Phlomis sect. Phlomoides and its generic status is not supported. With the inclusion of Lamiophlomis rotata in sect. Phlomoides, sections Phlomis and Phlomoides of Phlomis were resolved as monophyletic. Paraphlomis was supported as an independent genus. However, the resolution of its monophyly conflicted between MP and Bayesian analyses, suggesting the need for expended sampling and further evidence. [source] Osmoregulation in Six Sympatric Fiddler Crabs (genus Uca) from the Northwestern Gulf of MexicoMARINE ECOLOGY, Issue 4 2002Carl L. Thurman Abstract. As problems in taxonomy and systematic relationships among the Uca species are resolved, a definition of how each fiddler crab species partitions and utilizes habitat resources is needed. To this end, the osmoregulatory capabilities were studied in six species of fiddler crabs from the western Gulf of Mexico. Specimens were placed in 50,ml of artificial seawater ranging in osmolality from 50 to 3450,mOsm (2 to 109,,) for five days. Survivorship was recorded for each species. Uca rapax, U. panacea and U. subcylindrica are hardy from 200 to 3200,mOsm (6 to 101,,). Uca spinicarpa and U. minax survive only below 1400,mOsm (44,,). U. longisignalis is intermediate, with limited survival above 2500,mOsm (79,,). Hemolymph osmolality was determined for crabs surviving the osmotic regimen. Uca panacea, U. subcylindrica and U. rapax are equivalent in their regulation between 50 and 3200,mOsm (2,,,101,,). Uca longisignalis lost its ability to control hemolymph osmolality above 2200,mOsm (69,,). On the other hand, U. spinicarpa and U. minax become less effective hyporegulators in media above 1200 (38,,) and 1500,mOsm (47,,), respectively. Only U. longisignalis appears to exhibit clear differences in osmoregulatory capacity between populations. Population data for U. panacea and laboratory experiments with U. subcylindrica also support the notion of capacitative acclimation in Uca. These physiological capabilities correlate well with the known habitat characteristics for each fiddler crab species in the northwestern Gulf of Mexico. [source] World-wide genetic differentiation of Eubalaena: questioning the number of right whale speciesMOLECULAR ECOLOGY, Issue 11 2000H. C. Rosenbaum Abstract Few studies have examined systematic relationships of right whales (Eubalaena spp.) since the original species descriptions, even though they are one of the most endangered large whales. Little morphological evidence exists to support the current species designations for Eubalaena glacialis in the northern hemisphere and E. australis in the southern hemisphere. Differences in migratory behaviour or antitropical distribution between right whales in each hemisphere are considered a barrier to gene flow and maintain the current species distinctions and geographical populations. However, these distinctions between populations have remained controversial and no study has included an analysis of all right whales from the three major ocean basins. To address issues of genetic differentiation and relationships among right whales, we have compiled a database of mitochondrial DNA control region sequences from right whales representing populations in all three ocean basins that consist of: western North Atlantic E. glacialis, multiple geographically distributed populations of E. australis and the first molecular analysis of historical and recent samples of E. glacialis from the western and eastern North Pacific Ocean. Diagnostic characters, as well as phylogenetic and phylogeographic analyses, support the possibility that three distinct maternal lineages exist in right whales, with North Pacific E. glacialis being more closely related to E. australis than to North Atlantic E. glacialis. Our genetic results provide unequivocal character support for the two usually recognized species and a third distinct genetic lineage in the North Pacific under the Phylogenetic Species Concept, as well as levels of genetic diversity among right whales world-wide. [source] Cranial allometry, phylogeography, and systematics of large-bodied papionins (primates: Cercopithecinae) inferred from geometric morphometric analysis of landmark dataTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 2 2003Stephen R. Frost Abstract The cranial morphology of the African Old World monkeys Mandrillus, Papio, and Theropithecus (i.e., baboons) has been the subject of a number of studies investigating their systematic relationships, patterns of scaling, and growth. In this study, we use landmark-based geometric morphometrics and multivariate analysis to assess the effects of size, sex, taxonomy, and geographic location on cranial shape. Forty-five landmarks were digitized in three dimensions on 452 baboon crania and subjected to generalized Procrustes analysis (GPA), which standardizes geometric size but leaves scaling-based shape differences in the data. The resulting shape coordinates were submitted to regression analysis, principal components analysis (PCA), partial least-squares (PLS) analysis, and various clustering techniques. Scaling (shape differences correlated with size) was the largest single factor explaining cranial shape variation. For instance, most (but not all) of the shape differences between the sexes were explained by size dimorphism. However, central tendencies of shape clearly varied by taxon (both specific and subspecific) even after variations in size and sex were adjusted out. Within Papio, about 60% of the size- and sex-adjusted shape variations were explained by the geographic coordinates of the specimen's provenance, revealing a stepped cline in cranial morphology, with the greatest separation between northern and southern populations. Based on evidence from genetic studies, and the presence of at least two major hybrid/interbreeding zones, we interpret the phylogeographic pattern of cranial variation as indicating that these populations are best ranked as subspecies of a single species, rather than as two or more distinct biological species. This objective approach can be applied to other vertebrate species or species groups to help determine the taxonomic rank of problematic taxa. Anat Rec Part A 275A:1048,1072, 2003. © 2003 Wiley-Liss, Inc. [source] | |||||||||||||||||||