TY  - JOUR
A1  - Nahavandi, Nahid
A1  - Ketmaier, Valerio
A1  - Plath, Martin
A1  - Tiedemann, Ralph
T1  - Diversification of Ponto-Caspian aquatic fauna - morphology and molecules retrieve congruent evolutionary relationships in Pontogammarus maeoticus (Amphipoda: Pontogammaridae)
JF  - Molecular phylogenetics and evolution
N2  - The geological history of the Ponto-Caspian region, with alternating cycles of isolation and reconnection among the three main basins (Black and Azov Seas, and the more distant Caspian Sea) as well as between them and the Mediterranean Sea, profoundly affected the diversification of its aquatic fauna, leading to a high degree of endemism. Two alternative hypotheses on the origin of this amazing biodiversity have been proposed, corresponding to phases of allopatric separation of aquatic fauna among sea basins: a Late Miocene origin (10-6 MYA) vs. a more recent Pleistocene ancestry (<2 MYA). Both hypotheses support a vicariant origin of (1) Black + Azov Sea lineages on the one hand, and (2) Caspian Sea lineages on the other. Here, we present a study on the Ponto-Caspian endemic amphipod Pontogammarus maeoticus. We assessed patterns of divergence based on (a) two mitochondrial and one nuclear gene, and (b) a morphometric analysis of 23 morphological traits in 16 populations from South and West Caspian Sea, South Azov Sea and North-West Black Sea. Genetic data indicate a long and independent evolutionary history, dating back from the late Miocene to early Pleistocene (6.6-1.6 MYA), for an unexpected, major split between (i) a Black Sea clade and (ii) a well-supported clade grouping individuals from the Caspian and Azov Seas. Absence of shared haplotypes argues against either recent or human-mediated exchanges between Caspian and Azov Seas. A mismatch distribution analysis supports more stable population demography in the Caspian than in the Black Sea populations. Morphological divergence largely followed patterns of genetic divergence: our analyses grouped samples according to the basin of origin and corroborated the close phylogenetic affinity between Caspian and Azov Sea lineages. Altogether, our results highlight the necessity of careful (group-specific) evaluation of evolutionary trajectories in marine taxa that should certainly not be inferred from the current geographical proximity of sea basins alone. (C) 2013 Elsevier Inc. All rights reserved.
KW  - Biodiversity hotspot
KW  - Black Sea
KW  - Caspian Sea
KW  - Paratethys
KW  - Sea of Azov
KW  - Vicariance
Y1  - 2013
U6  - https://doi.org/10.1016/j.ympev.2013.05.021
SN  - 1055-7903
SN  - 1095-9513
VL  - 69
IS  - 3
SP  - 1063
EP  - 1076
PB  - Elsevier
CY  - San Diego
ER  - 
TY  - JOUR
A1  - Plath, Martin
A1  - Pfenninger, Markus
A1  - Lerp, Hannes
A1  - Riesch, Rüdiger
A1  - Eschenbrenner, Christoph
A1  - Slattery, Patrick A.
A1  - Bierbach, David
A1  - Herrmann, Nina
A1  - Schulte, Matthias
A1  - Arias-Rodriguez, Lenin
A1  - Rimber Indy, Jeane
A1  - Passow, Courtney
A1  - Tobler, Michael
T1  - Genetic differentiation and selection against migrants in evolutionarily replicated extreme environments
JF  - Evolution
N2  - We investigated mechanisms of reproductive isolation in livebearing fishes (genus Poecilia) inhabiting sulfidic and nonsulfidic habitats in three replicate river drainages. Although sulfide spring fish convergently evolved divergent phenotypes, it was unclear if mechanisms of reproductive isolation also evolved convergently. Using microsatellites, we found strongly reduced gene flow between adjacent populations from different habitat types, suggesting that local adaptation to sulfidic habitats repeatedly caused the emergence of reproductive isolation. Reciprocal translocation experiments indicate strong selection against immigrants into sulfidic waters, but also variation among drainages in the strength of selection against immigrants into nonsulfidic waters. Mate choice experiments revealed the evolution of assortative mating preferences in females from nonsulfidic but not from sulfidic habitats. The inferred strength of sexual selection against immigrants (RIs) was negatively correlated with the strength of natural selection (RIm), a pattern that could be attributed to reinforcement, whereby natural selection strengthens behavioral isolation due to reduced hybrid fitness. Overall, reproductive isolation and genetic differentiation appear to be replicated and direct consequences of local adaptation to sulfide spring environments, but the relative contributions of different mechanisms of reproductive isolation vary across these evolutionarily independent replicates, highlighting both convergent and nonconvergent evolutionary trajectories of populations in each drainage.
KW  - Ecological speciation
KW  - isolation-by-adaptation
KW  - local adaptation
KW  - Poecilia mexicana
KW  - reinforcement
KW  - sexual isolation
Y1  - 2013
U6  - https://doi.org/10.1111/evo.12133
SN  - 0014-3820
VL  - 67
IS  - 9
SP  - 2647
EP  - 2661
PB  - Wiley-Blackwell
CY  - Hoboken
ER  -