posted on 2016-11-18, 10:05authored byAgnieszka Konowalik, Anna Najbar, Wiesław Babik, Sebastian Steinfartz, Maria Ogielska
We analysed genetic variation within and
differentiation between nineteen populations of the fire salamander Salamandra
salamandra inhabiting the north-eastern margin of the species range in the
Sudetes Mountains (south-western Poland). The results were compared with those
obtained recently for the Polish part of the Carpathians. Variation of 10
nuclear microsatellite loci was analysed in 744 individuals to estimate genetic
structure, gene flow, isolation and to test for a geographic gradient of
genetic variation. Mitochondrial DNA control region (D-loop) of 252 specimens
from all localities was used to identify the origin of populations currently
inhabiting its north-eastern range. We found little genetic differentiation
among populations in the Sudetes indicating substantial recent or ongoing gene
flow. The exceptions were one isolated peripheral population located outside
the continuous distribution range which displayed extremely reduced genetic
variation probably due to a combination of long term isolation and low
population size, and one population located at the eastern margin of the Polish
Sudetes. Populations inhabiting the Sudetes and the Carpathians formed two
separate clusters based on microsatellite loci. In accordance with available phylogeographic
information, single mitochondrial haplotype (type IIb) fixed in all populations
indicates their origin from a single refugium and may suggest colonization from
the Balkan Peninsula. The analysis of geographic gradient in variation showed its
decline in the westerly direction suggesting colonization of Poland from the
east, however, alternative scenarios of postglacial colonization could not be
rejected with the available data.