Editing Smooth newt (section)

==Evolution==

[[Molecular phylogenetic]] analyses have shown that the smooth newt is distinct from its four close relatives''&nbsp;''– the Caucasian, Greek, Kosswig's, and Schmidtler's smooth newt – which were formerly considered subspecies (see section ''Taxonomy'' above). The relationships within this species complex have not been fully resolved. Within the smooth newt itself, genetic groups do not completely match the currently accepted subspecies (''ampelensis'', ''meridionalis'', ''vulgaris''), described based on morphology.{{r|PabijanZielinski2017}} The five smooth newt species collectively were estimated to have [[Genetic divergence|diverged]] from the Carpathian newt around four to six million years ago.{{r|ZielińskiNadachowska-Brzyska2016|PabijanZieliński2015}}

Genetic analyses have also demonstrated ongoing [[gene flow]] between the smooth newt and its relatives. Although the Carpathian newt is morphologically clearly different, [[hybridisation (biology)|hybridisation]] between the two species is frequent;{{r|Grosse2011|p=26}} it has been shown that smooth newt [[mitochondrial DNA]] has [[introgression|introgressed]] into and completely replaced that of the Carpathian newt populations.{{r|BabikBranicki2005}} Partial introgression also occurred from the smooth newt to the Greek smooth newt.{{r|PabijanZielinski2017}} These patterns are likely due to the range expansion and [[secondary contact]] of species after the [[Last Glacial Maximum]], which they likely survived in [[refugium (population biology)|refugia]] mainly in southern and eastern Europe.{{r|BabikBranicki2005|PabijanZieliński2015|SkorinovLitvinchuk2016}} The [[palmate newt]] (''Lissotriton helveticus''), although often occurring in the same habitats, almost never hybridises with the smooth newt.{{r|Grosse2011|p=25}} Artificial crosses with even more distant species such as the [[alpine newt|alpine]] (''Ichthyosaura alpestris'') and [[northern crested newt|northern crested]] (''Triturus cristatus'') newts were successful in laboratory experiments.{{r|Grosse2011|p=29}}