| 1. |
- Dunn, Casey W, et al.
(författare)
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Broad phylogenomic sampling improves resolution of the animal tree of life.
- 2008
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 452:7188, s. 745-9
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Tidskriftsartikel (refereegranskat)abstract
- Long-held ideas regarding the evolutionary relationships among animals have recently been upended by sometimes controversial hypotheses based largely on insights from molecular data. These new hypotheses include a clade of moulting animals (Ecdysozoa) and the close relationship of the lophophorates to molluscs and annelids (Lophotrochozoa). Many relationships remain disputed, including those that are required to polarize key features of character evolution, and support for deep nodes is often low. Phylogenomic approaches, which use data from many genes, have shown promise for resolving deep animal relationships, but are hindered by a lack of data from many important groups. Here we report a total of 39.9 Mb of expressed sequence tags from 29 animals belonging to 21 phyla, including 11 phyla previously lacking genomic or expressed-sequence-tag data. Analysed in combination with existing sequences, our data reinforce several previously identified clades that split deeply in the animal tree (including Protostomia, Ecdysozoa and Lophotrochozoa), unambiguously resolve multiple long-standing issues for which there was strong conflicting support in earlier studies with less data (such as velvet worms rather than tardigrades as the sister group of arthropods), and provide molecular support for the monophyly of molluscs, a group long recognized by morphologists. In addition, we find strong support for several new hypotheses. These include a clade that unites annelids (including sipunculans and echiurans) with nemerteans, phoronids and brachiopods, molluscs as sister to that assemblage, and the placement of ctenophores as the earliest diverging extant multicellular animals. A single origin of spiral cleavage (with subsequent losses) is inferred from well-supported nodes. Many relationships between a stable subset of taxa find strong support, and a diminishing number of lineages remain recalcitrant to placement on the tree.
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| 2. |
- Forero Mejia, Anny C., et al.
(författare)
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Molecular phylogeny of Ceriantharia (Cnidaria:Anthozoa) reveals non-monophyly of traditionally accepted families
- 2020
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Ingår i: Zoological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4082 .- 1096-3642. ; 190:2, s. 397-416
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Tidskriftsartikel (refereegranskat)abstract
- We present an integrative study with molecular phylogenetic reconstructions and morphological assessment across the three Ceriantharia families: Arachnactidae, Botrucnidiferidae and Cerianthidae. The Arachnactidae specimens (Isarachnanthus spp.) form a well-supported clade, whereas Cerianthidae and Botrucnidiferidae are not recovered as monophyletic. Consequently, the validity of the suborder Spirularia is questioned. Cerianthus was recovered as polyphyletic and Ceriantheomorphe may prove to be a junior synonym of Cerianthus. The taxonomic position of Cerianthus cf. mortenseni is also discussed. All specimens identified on morphology as belonging to Pachycerianthus are recovered as a clade. Further revision of taxa within Ceriantharia is necessary. Molecular phylogenetic analyses based on six mitochondrial or nuclear loci place Ceriantharia as sister to Hexacorallia s.s., but with no significant support relative to an alternative hypothesis that it is the sister taxon to Octocorallia. Further molecular sequence data and taxon sampling will be needed to resolve the position of Ceriantharia.
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| 3. |
- Pleijel, Fredrik, 1955, et al.
(författare)
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Progress in systematics: from Siboglinidae to Pogonophora and Vestimentifera and back to Siboglinidae
- 2009
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Ingår i: Comptes rendus de l'Academie des sciences. - : Elsevier BV. ; 332:2-3, s. 140-148
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Forskningsöversikt (refereegranskat)abstract
- We review the taxonomic history of pogonophores (frenulates and vestimentiferans), from the species in first described 1914 to the recently described bone-eating worm Osedax. Previous systematists have referred both groups to the rank of phylum, and the animals have been treated as deuterostomes with a dorsal nerve cord. Further knowledge on their embryology, the discovery of the previously overlooked posterior, segmented part provided with chaetae, and access to molecular data, have completely changed earlier views on their affinities. They are now referred to as a single family of polychaete annelids, Siboglinidae.
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| 4. |
- Rouse, Greg W, et al.
(författare)
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Annelida
- 2007
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Ingår i: Zootaxa. - 1175-5326. ; :1668, s. 245-264
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Tidskriftsartikel (refereegranskat)
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| 5. |
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| 6. |
- Zhang, Yanjie, et al.
(författare)
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Phylogeny, evolution and mitochondrial gene order rearrangement in scale worms (Aphroditiformia, Annelida)
- 2018
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 125, s. 220-231
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 Elsevier Inc. Next-generation sequencing (NGS) has become a powerful tool in phylogenetic and evolutionary studies. Here we applied NGS to recover two ribosomal RNA genes (18S and 28S) from 16 species and 15 mitochondrial genomes from 16 species of scale worms representing six families in the suborder Aphroditiformia (Phyllodocida, Annelida), a complex group of polychaetes characterized by the presence of dorsal elytra or scales. The phylogenetic relationship of the several groups of scale worms remains unresolved due to insufficient taxon sampling and low resolution of individual gene markers. Phylogenetic tree topology based on mitochondrial genomes is comparable with that based on concatenated sequences from two mitochondrial genes (cox1 and 16S) and two ribosomal genes (18S and 28S) genes, but has higher statistical support for several clades. Our analyses show that Aphroditiformia is monophyletic, indicating the presence of elytra is an apomorphic trait. Eulepethidae and Aphroditidae together form the sister group to all other families in this suborder, whereas Acoetidae is sister to Iphionidae. Polynoidae is monophyletic, but within this family the deep-sea subfamilies Branchinotogluminae and Macellicephalinae are paraphyletic. Mitochondrial genomes in most scale-worm families have a conserved gene order, but within Polynoidae there are two novel arrangement patterns in the deep-sea clade. Mitochondrial protein-coding genes in polynoids as a whole have evolved under strong purifying selection, but substitution rates in deep-sea species are much higher than those in shallow-water species, indicating that purifying selection is relaxed in deep-sea polynoids. There are positive selected amino acids for some mitochondrial genes of the deep-sea clade, indicating they may involve in the adaption of deep-sea polynoids. Overall, our study (1) provided more evidence for reconstruction of the phylogeny of Aphroditiformia, (2) provided evidence to refute the assumption that mitochondrial gene order in Errantia is conserved, and (3) indicated that the deep-sea extreme environment may have affected the mitochondrial genome evolution rate and gene order arrangement in Polynoidae.
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