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Micropontica populations from Lagonaki plateau in the Caucasus are homoploid hybrids.
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They form a genetic cluster distinct from the parental species and are characterized by a mtDNA haplotype clade.
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These haplotypes are presumably better adapted to high altitude habitats.
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They replaced the haplotypes of the parental species in a selective sweep.
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The fixation of an adaptive haplotype clade is an important step towards speciation.