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- Olsson, Urban, 1954, et al.
(författare)
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Non-monophyly of the avian genus Seicercus (Aves : Sylviidae) revealed by mitochondrial DNA
- 2004
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Ingår i: Zoologica Scripta. - Gothenburg Univ, Dept Zool, SE-40530 Gothenburg, Sweden. Uppsala Univ, Evolutionary Biol Ctr, Dept Systemat Zool, SE-75236 Uppsala, Sweden. : Wiley. - 0300-3256 .- 1463-6409. ; 33:6, s. 501-510
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Tidskriftsartikel (refereegranskat)abstract
- The phylogeny of all species and nearly all subspecies of Seicercus and representatives of all subgenera in Phylloscopus was estimated based on two mitochondrial genes. According to the gene tree, and supported by non-molecular data, Seicercus belongs in three separate clades. Two of these include only taxa currently classified as Seicercus, while the third comprises S. xanthoschistos and P. occipitalis. These results suggest that both Seicercus and Phylloscopus are paraphyletic. The gene tree suggests two more cases of non-monophyly: (1) the 'S. burkii complex' is separated into two different clades, one of which also includes S. affinis and S. poliogenys; (2) two populations of S. affinis intermedius are more closely related to S. affinis ocularis than to a third population of intermedius. A recent proposal to split the 'S. burkii complex' into six species is corroborated, as is the recognition of the taxon cognitus as a colour morph of S. affinis intermedius. Our study also revealed unexpectedly large genetic divergences between three different populations of the monotypic S. poliogenys, indicating the presence of cryptic species. Our results underscore the importance of dense sampling at the specific and infraspecific levels in intrageneric phylogenetic studies.
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| 2. |
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| 3. |
- Alström, Per, Professor, et al.
(författare)
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Golden-spectacled Warbler systematics
- 2000
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Ingår i: IBIS. - : BRITISH ORNITHOLOGISTS UNION. - 0019-1019 .- 1474-919X. ; 142:3
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Annan publikation (övrigt vetenskapligt/konstnärligt)
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| 4. |
- Alström, Per
(författare)
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Species Limits and Systematics in Some Passerine Birds
- 2002
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- I use morphological, vocal, molecular, behavioural, ecological and distributional data to re-evaluate the systematics of three passerine bird groups, the Mirafraassamica complex (bush-larks), the genus Seicercus ("spectacled-warblers"; with emphasis on the the S. burkii complex) and the genus Motacilla (wagtails). Two new species are described: Seicercus soror and Motacilla samveasnae. I propose that the polytypic species M. assamica should be treated as four separate species: M. assamica, M. affinis, M. microptera and M. marionae (it is also remarked that the proper name of the latter is M. erythrocephala). That is primarily supported by vocalisations and mitochondrial DNA. The latter data set also suggests that M. assamica sensu lato is paraphyletic, since M. erythroptera, which is always treated as a separate species, is nested within the M. assamica complex. I propose that the polytypic species S. burkii comprises six sibling species. Some of these are found to breed sympatrically, although mainly or entirely segregated altitudinally. Mitochondrial DNA suggests that the S. burkii complex is non-monophyletic, and also that the divergence of the different taxa is much older than indicated by morphological and vocal data. According to the molecular phylogeny, both the genera Seicercus and its assumed sister genus Phylloscopus are paraphyletic. That is corroborated by independent data. The phylogenetic study of the genus Motacilla reveals incongruence between mitochondrial DNA, nuclear DNA and non-molecular data. I conclude that the nuclear gene tree reflects the organismal phylogeny more faithfully than the mitochondrial gene tree. The latter is likely to have been affected by introgressive hybridisation, possibly also stochastic lineage sorting. The most remarkable result that is strongly supported by both mitochondrial and nuclear DNA is that M. flava is non-monophyletic.
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| 5. |
- Irwin, D E, et al.
(författare)
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Cryptic species in the genus Phylloscopus (Old World leaf warblers)
- 2001
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Ingår i: Ibis. - Univ Calif San Diego, Dept Biol, La Jolla, CA 92093 USA. Uppsala Univ, Evolutionary Biol Ctr, Dept Systemat Zool, SE-75236 Uppsala, Sweden. Univ Gothenburg, Dept Zool, S-40530 Gothenburg, Sweden. : BRITISH ORNITHOLOGISTS UNION. - 0019-1019 .- 1474-919X. ; 143:2, s. 233-247
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Tidskriftsartikel (refereegranskat)abstract
- In almost all ecological and evolutionary research, it is important to assess the number of species under study. Cryptic species, which are morphologically similar, present a special problem because they need to be identified through studies of behavioural or genetic variation. Here we review the important factors in the recent discovery of three species and elevation of nine previously known taxa to species status within the genus Phylloscopus (Old World leaf-warblers] and we examine the case of three morphologically similar taxa (inornatus, humei and mandellii) that until recently were considered to be members of the single species Phylloscopus inornatus. We have identified several locations at which humei and inornatus coexist at high density, and the results of playback experiments, observations of interactions, and spectrogram analysis of vocalizations at these sites all indicate that there are significant behavioural differences and a lack of recognition between humei and inornatus. Estimated relationships within the species complex based on mitochondrial control region DNA sequences show that there is little variation within the geographic ranges of either humei or inornatus compared with the deep split between the two taxa. These observations support the division of humei and inornatus into separate species. The third taxon, mandellii, which is geographically separated from both humei and inornatus, is behaviourally and genetically more similar to humei. Under the biological species concept, it is difficult to determine the species status of allopatric taxa. Alternative species concepts, such as the phylogenetic and recognition concepts, are more easily applied to allopatric taxa but lead to differing conclusions over whether mandellii and humei are separate species. This confusion arises from the fact that the two taxa are in an early stage of allopatric divergence. The review of other recently designated species reveals that song divergence is of primary importance in their designation and that song variation, playback experiments and genetic analysis lead to similar conclusions regarding species status.
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