@article{488654ae1aa846f8b97ab74e1edba491,
title = "Extensive phenotypic diversification coexists with little genetic divergence and a lack of population structure in the White Wagtail subspecies complex (Motacilla alba)",
abstract = "Geographically clustered phenotypes often demonstrate consistent patterns in molecular markers, particularly mitochondrial DNA (mtDNA) traditionally used in phylogeographic studies. However, distinct evolutionary trajectories among traits and markers can lead to their discordance. First, geographic structure in phenotypic traits and nuclear molecular markers can be co-aligned but inconsistent with mtDNA (mito-nuclear discordance). Alternatively, phenotypic variation can have little to do with patterns in neither mtDNA nor nuclear markers. Disentangling between these distinct patterns can provide insight into the role of selection, demography and gene flow in population divergence. Here, we examined a previously reported case of strong inconsistency between geographic structure in mtDNA and plumage traits in a widespread polytypic bird species, the White Wagtail (Motacilla alba). We tested whether this pattern is due to mito-nuclear discordance or discrepancy between morphological evolution and both nuclear and mtDNA markers. We analysed population differentiation and structure across six out of nine commonly recognized subspecies using 17 microsatellite loci and a combination of microsatellites and plumage indices in a comprehensively sampled region of a contact between two subspecies. We did not find support for the mito-nuclear discordance hypothesis: nuclear markers indicated a subtle signal of genetic clustering only partially consistent with plumage groups, similar to previous findings that relied on mtDNA. We discuss evolutionary factors that could have shaped the intricate patterns of phenotypic diversification in the White wagtail and the role that repeated selection on plumage {\textquoteleft}hotspots{\textquoteright} and hybridization may have played.",
keywords = "mito-nuclear discordance, phenotypic diversification, plumage evolution, wagtail",
author = "Semenov, {Georgy A.} and Koblik, {Evgeniy A.} and Red'kin, {Yaroslav A.} and Badyaev, {Alexander V.}",
note = "Funding Information: We thank David Khaydarov, Andrey Lissovsky, Alex Katokhin, Evgeniy Khobotov, Alexander Yurlov, Evgeniy Davidyuk, Ilya Murashov, Evgeniy Shemyakin, Vladimir Sotnikov, Marko Rakovic, Georgii Bakhtadze, Nikolay Balatsky and Anatoliy Shapoval for their help with field sampling and for sharing tissue specimens. Authors thank Susana Lopes and Sandra Reis for their help with the lab work and Sergei Drovetski for the financial support in the development of microsatellite primers and the lab work. Four samples of personata from Kazakhstan were loaned by the University of Washington Burke Museum of Natural History and Culture (UWBM 46410, 46411, 46419, 46420) and two baicalensis by the Yale Peabody Museum of Natural History (YPM 140067, 140317). Authors thank Kristof Zys-kowski, Sharon Birks and Sergei Drovetski for their help with sample shipments. We thank Vladmir Loskot for granting access to collections of the Zoological Institute of the Russian Academy of Sciences. Erin Morrison, Ahva Potticary, Kelly Hallinger, David Zonana, Sheela Turbek and three anonymous reviewers provided helpful comments on the manuscript. This work was supported by grants from Russian Foundations for Basic Research 14-04-01492 and 12-04-31042 to GAS, Russian Science Foundation 14-50-00029 to YAR, Moscow State University AAAA-A16-116021660077-3 to YAR and EAK, and by the G.G. Simpson Postdoctoral Fellowship from the University of Arizona to GAS. We are grateful to Yulia Sheina for the wagtail drawings used in Figs 1,2 and 4 and to Angel Gar{\'c}ıa for granting permission to publish the photograph of Motacilla alba subpersonata. Sampling was carried out with necessary collecting permissions granted to ZMMSU, SZM and KCZM. No authors have any conflict of interest to declare. Publisher Copyright: {\textcopyright} 2018 European Society For Evolutionary Biology. Journal of Evolutionary Biology {\textcopyright} 2018 European Society For Evolutionary Biology",
year = "2018",
month = aug,
doi = "10.1111/jeb.13305",
language = "English (US)",
volume = "31",
pages = "1093--1108",
journal = "Journal of Evolutionary Biology",
issn = "1010-061X",
publisher = "Wiley-Blackwell",
number = "8",
}