Divergent clades or cryptic species? Mito-nuclear discordance in a Daphnia species complex
| Autor: | Ali Mohammadyari, Adam Petrusek, Klaus Schwenk, Anne Thielsch, Alexis Knell |
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| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0106 biological sciences
0301 basic medicine Mitochondrial DNA Species complex Evolution Introgression Zoology Biology 010603 evolutionary biology 01 natural sciences DNA Mitochondrial Coalescent theory Interspecific hybridization 03 medical and health sciences Common species Species Specificity QH359-425 Animals Ecology Evolution Behavior and Systematics Phylogeny Cell Nucleus Daphnia longispina complex Phylogenetic tree Genetic Variation Ancestral polymorphism Cladocera Incomplete lineage sorting 030104 developmental biology Adaptive introgression Daphnia Evolutionary biology Biological dispersal Hybridization Genetic Gene pool Microsatellite Repeats Research Article |
| Zdroj: | BMC Evolutionary Biology, Vol 17, Iss 1, Pp 1-9 (2017) BMC Evolutionary Biology |
| ISSN: | 1471-2148 |
| Popis: | Background Genetically divergent cryptic species are frequently detected by molecular methods. These discoveries are often a byproduct of molecular barcoding studies in which fragments of a selected marker are used for species identification. Highly divergent mitochondrial lineages and putative cryptic species are even detected in intensively studied animal taxa, such as the crustacean genus Daphnia. Recently, eleven such lineages, exhibiting genetic distances comparable to levels observed among well-defined species, were recorded in the D. longispina species complex, a group that contains several key taxa of freshwater ecosystems. We tested if three of those lineages represent indeed distinct species, by analyzing patterns of variation of ten nuclear microsatellite markers in six populations. Results We observed a discordant pattern between mitochondrial and nuclear DNA, as all individuals carrying one of the divergent mitochondrial lineages grouped at the nuclear level with widespread, well-recognized species coexisting at the same localities (Daphnia galeata, D. longispina, and D. cucullata). Conclusions A likely explanation for this pattern is the introgression of the mitochondrial genome of undescribed taxa into the common species, either in the distant past or after long-distance dispersal. The occurrence of highly divergent but rare mtDNA lineages in the gene pool of widespread species would suggest that hybridization and introgression in the D. longispina species complex is frequent even across large phylogenetic distances, and that discoveries of such distinct clades must be interpreted with caution. However, maintenance of ancient polymorphisms through selection is another plausible alternative that may cause the observed discordance and cannot be entirely excluded. Electronic supplementary material The online version of this article (10.1186/s12862-017-1070-4) contains supplementary material, which is available to authorized users. |
| Databáze: | OpenAIRE |
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