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Paco Cárdenas Hans Tore Rapp Christoffer Schander Ole S. Tendal 《Zoologica scripta》2010,39(1):89-106
Cárdenas, P., Rapp, H. T., Schander, C. & Tendal, O. S. (2009). Molecular taxonomy and phylogeny of the Geodiidae (Porifera, Demospongiae, Astrophorida) – combining phylogenetic and Linnaean classification.—Zoologica Scripta, 39, 89–106. According to the fossil records, the Geodiidae represents one of the oldest families of demosponges (Phylum Porifera). There are approximately 220 described extant species, geographically and bathymetrically widely distributed around the world. Species of this family all share a two-layered cortex with ball-shaped spicules called ‘sterrasters’ in the endocortex. However, molecular studies have questioned the monophyly of the group. Moreover, the evolutionary history and the intrafamily relationships of the Geodiidae are not fully resolved. Using a partial sequence of the cytochrome c oxidase subunit 1 (COI) gene and a partial sequence of the 28S rDNA gene (D1–D2 domains), we present the first molecular phylogeny focusing on this group. The congruent results from the two gene fragments suggest that (i) the Geodiidae is monophyletic, (ii) the Erylinae/Geodinae subdivision sensu Sollas, 1888 is valid and that (iii) Isops and Sidonops are junior synonyms of Geodia. The synonymization of Isops and Sidonops implies that the oscule/pore morphology as a diagnostic character should be abandoned. Geodia hentscheli nom. nov. has been given for Geodia mesotriaena ( Hentschel, 1929 ). This study served as the basis for a revised phylogenetic classification of the Geodiidae. Well-supported clades led to the establishment of clade names following the PhyloCode. The Geodinae clade is strongly supported and notably composed of Depressiogeodia, Cydonium and Geodia. A morphological synapomorphy of Geodinae is the presence of euasters in the ectocortex. The Erylinae (Erylus, Penares, Caminus and Pachymatisma) form a strongly supported monophyletic group with three morphological synapomorphies: (i) loss of anatriaenes and protriaenes, (ii) microrhabds (or spherules) in the ectocortex and (iii) short-shafted triaenes. The Erylus monophyly is ambiguous. Erylus species are distributed in three well-supported clades. Finally, spicule homology in the cortex of the Geodiidae is discussed. 相似文献
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Mihaela Ilieva David P.L. Toews Staffan Bensch Christoffer Sjöholm Susanne Åkesson 《Behavioural processes》2012
Topography and historical range expansion has formed a so-called migratory divide between two subspecies of willow warbler (Phylloscopus trochilus) in central Scandinavia. The autumn migratory directions of individuals assigned molecularly to both subspecies and possible hybrids were recorded using orientation cage experiments in southwest and southeast Sweden. We found pronounced differences in willow warblers’ orientation in respect to genotype. The mean directions registered in the control experiments were in accordance with the ringing recoveries and analyses of stable isotopes for Scandinavian willow warblers. With the same individuals we performed displacement experiments between both sites. They resulted in non-significant orientation, which could be explained by the intermediate distance of the displacement or reactions to housing, transportation and location. On a separate set of birds we tested whether stress following transportation could explain the disorientation and found that orientation before and after transport was unchanged. Experimental studies of effects of intermediate displacements across longitudes and studies of orientation of hybrid individuals in the zones of migratory divides are crucial for understanding the mechanisms underlying orientation behaviour. Our work further stresses the importance of knowing the migration genotype of a particular bird under study, in order to correctly evaluate expected migration routes. 相似文献
205.
Helmut Schander 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1958,28(3):105-132
Ohne ZusammenfassungMit 11 AbbildungenDem Pflanzenzüchter Herrn Professor Dr.Reinhold von Sengbusch zum 60. Geburtstag gewidmet. 相似文献
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