10.5061/DRYAD.6QV8666
Dufresnes, Christophe
University of Lausanne
Lymberakis, Petros
University of Crete
Kornilios, Panagiotis
University of Patras
Savary, Romain
University of Lausanne
Perrin, Nicoals
University of Lausanne
Stöck, Matthias
Leibniz Institute of Freshwater Ecology and Inland Fisheries
Data from: Phylogeography of Aegean green toads (Bufo viridis subgroup):
continental hybrid swarm vs. insular diversification with discovery of a
new island endemic
Dryad
dataset
2018
Bufo viridis
Holocene
Bufo variabilis
National Science Foundation
https://ror.org/021nxhr62
Deutsche Forschungsgemeinschaft DFG Sto 493/2–2; Swiss National Science
Foundation (P2LAP3_171818)
2018-04-17T17:25:29Z
2018-04-17T17:25:29Z
en
https://doi.org/10.1186/s12862-018-1179-0
81912 bytes
1
CC0 1.0 Universal (CC0 1.0) Public Domain Dedication
Background: Debated aspects in speciation research concern the amount of
gene flow between incipient species under secondary contact and the modes
by which post-zygotic isolation accumulates. Secondary contact zones of
allopatric lineages, involving varying levels of divergence, provide
natural settings for comparative studies, for which the Aegean (Eastern
Mediterranean) geography offers unique scenarios. In Palearctic green
toads (Bufo viridis subgroup or Bufotes), Plio-Pleistocene (~2.6 Mya)
diverged species show a sharp transition without contemporary gene flow,
while younger lineages, diverged in the Lower-Pleistocene (~1.9 Mya),
admix over tens of kilometers. Here, we conducted a fine-scale multilocus
phylogeographic analysis of continental and insular green toads from the
Aegean, where a third pair of taxa, involving Mid-Pleistocene diverged
(~1.5 Mya) mitochondrial lineages, earlier tentatively named viridis and
variabilis, (co-)occurs. Results: We discovered a new lineage, endemic to
Naxos (Central Cyclades), while coastal islands and Crete feature weak
genetic differentiation from the continent. In continental Greece, both
lineages, viridis and variabilis, form a hybrid swarm, involving massive
mitochondrial and nuclear admixture over hundreds of kilometers, without
obvious selection against hybrids. Conclusions: The genetic signatures of
insular Aegean toads appear governed by bathymetry and Quaternary sea
level changes, resulting in long-term isolation (Central Cyclades: Naxos)
and recent land-bridges (coastal islands). Conversely, Crete has been
isolated since the end of the Messinian salinity crisis (5.3 My) and
Cretan populations thus likely result from human-mediated colonization, at
least since Antiquity, from Peloponnese and Anatolia. Comparisons of green
toad hybrid zones support the idea that post-zygotic hybrid
incompatibilities accumulate gradually over the genome. In this radiation,
only one million years of divergence separate a scenario of complete
reproductive isolation, from a secondary contact resulting in near
panmixia.
BufoGreeceMicrosatelliteDataMtDNAHaplotypes_DufresnesEtAl2018Contains
locality number, sample ID, mtDNA haplotype group (lineage),
alpha-tropomyosin genotype, and alleles of seven microsatellites
(Excel-table).
Greece
Turkey
Aegean Sea
Asia Minor
Balkan Peninsula