Data from: The role of geography and ecology in shaping repeated patterns of morphological and genetic differentiation between European minnows (Phoxinus phoxinus) from the Pyrenees and the Alps

Neutral and selective processes can drive repeated patterns of evolution
in different groups of populations experiencing similar ecological
gradients. In this paper, we used a combination of nuclear and
mitochondrial DNA markers, as well as geometric morphometrics, to
investigate repeated patterns of morphological and genetic divergence of
European minnows in two mountain ranges: the Pyrenees and the Alps.
European minnows (Phoxinus phoxinus) are cyprinid fish inhabiting most
freshwater bodies in Europe, including those in different mountain ranges
that could act as major geographical barriers to gene flow. We explored
patterns of P. phoxinus phenotypic and genetic diversification along a
gradient of altitude common to the two mountain ranges, and tested for
isolation by distance (IBD), isolation by environment (IBE) and isolation
by adaptation (IBA). The results indicated that populations from the
Pyrenees and the Alps belong to two well differentiated, reciprocally
monophyletic mtDNA lineages. Substantial genetic differentiation due to
geographical isolation within and between populations from the Pyrenees
and the Alps was also found using rapidly evolving AFLPs markers
(isolation by distance or IBD), as well as morphological differences
between mountain ranges. Also, morphology varied strongly with elevation
and so did genetic differentiation to a lower extent. Despite moderate
evidence for IBE and IBA, and therefore of repeated evolution, substantial
population heterogeneity was found at the genetic level, suggesting that
selection and population specific genetic drift act in concert to affect
genetic divergence.