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- Koblmueller, Stephan, et al.
(författare)
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Age and spread of the haplochromine cichlid fishes in Africa
- 2008
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 49:1, s. 153-169
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Tidskriftsartikel (refereegranskat)abstract
- The Haplochromini are by far the most species-rich cichlid fish tribe that originated along with the so-called primary radiation of the Lake Tanganyika cichlid species flock, i.e. at the same time during which the majority of the endemic Lake Tanganyika cichlid tribes emerged. Unlike the other tribes, the haplochromines are not restricted to Lake Tanganyika but distributed throughout Africa, except for the northwestern part of the continent. Haplochromine cichlids seeded the adaptive radiation of cichlid fishes in Lakes Malawi, Kivu, Victoria, Turkana, as well as in the now extinct paleo-Lake Makgadikgadi. Here we present a comprehensive phylogenetic and phylogeographic analysis of haplochromine cichlids that is based upon DNA sequences of two mitochondrial gene segments of riverine taxa covering all major African biogeographic regions where haplochromines are found. Our analysis revealed that six lineages of haplochromines originated within a short period of time, about 5.3-4.4 MYA. These haplochromine lineages show a highly complex phylogeographic pattern, probably severely influenced by climate- and/or geology-induced changes of the environment, with river capture events most likely playing an important role for species dispersal. (C) 2008 Elsevier Inc. All rights reserved.
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2. |
- Koblmuller, Stephan, et al.
(författare)
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Phylogeographic structure and gene flow in the scale-eating cichlid Perissodus microlepis (Teleostei, Perciformes, Cichlidae) in southern Lake Tanganyika
- 2009
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Ingår i: Zoologica Scripta. - : Wiley. - 0300-3256 .- 1463-6409. ; 38:3, s. 257-268
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Tidskriftsartikel (refereegranskat)abstract
- One of the most fragmented habitats in freshwater lakes is the rocky littoral zone, where the already richly structured habitat is frequently interspersed with more pronounced barriers such as sandy bays, river estuaries and deep slopes. Although habitat fragmentation generally constrains the dispersal of specialized rock-dwelling species, patterns of population structure vary in sympatric taxa due to species-specific traits. In the present study, we examine the phylogeographic and population genetic structure of Perissodus microlepis, a presumptively highly mobile scale-eating cichlid fish endemic to Lake Tanganyika with a lake-wide distribution in the rocky littoral zone and no obvious geographical colour variation. Analysis of the mitochondrial DNA of six populations in the southern end of the lake suggests isolation by distance along rocky shoreline. Across a large muddy bay, a phylogeographic break indicates that environmental barriers restrict gene flow even in this highly mobile species. Restricted dispersal across the bay is not necessarily a consequence of an intrinsic propensity to avoid sand, but may be connected with the association between P. microlepis and other rock-dwelling fish, which the scale-eaters mimic and intermingle in order to be able to approach other fish to rip off scales from their bodies.
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