The succession of glacials and interglacials during the Pleistocene strongly influenced the diversification and distribution patterns in birds. In contrast to species of temperate regions, open-habitat specialists should have experienced range expansion during the longer glacial periods, while range contractions occurred during the shorter interglacials. However, only few studies have tested this prediction so far. We studied the Oenanthe hispanica–pleschanka–cypriaca (Aves, Muscicapidae: Saxicolinae) complex characteristic of open habitats in the Palearctic. Based on three mitochondrial and one Z-linked nuclear marker, we inferred its phylogeny, historical diversification, and demography. Ecological niche modeling was used to reconstruct potential distributions during the last glacial maximum and the last interglacial. Using 19 morphological traits, we tested for morphometric differences among the different taxa. Mitochondrial markers revealed strong genetic differences between O. h. hispanica and the other taxa with a divergence event at around 1.7 million years ago. No consistent genetic differences were revealed between O. cypriaca, O. h. melanoleuca, and O. pleschanka. The latter two hybridize in contact zones, which might explain partly the lack of genetic differentiation; yet, further analyses using genomic data are needed to infer the true divergence history of the complex. Signs of population expansions in the clade comprising O. h. melanoleuca, O. pleschanka, and O. cypriaca at 90,000 years ago coincided with the last glacial as predicted. Population expansion then was also supported by ecological climate niche models. O. h. hispanica was not consistently separated from the other taxa in morphometrics. It might nonetheless warrant species status, pending further analyses.
Alaei Kakhki N, Aliabadian M, Förschler MI, et al. Phylogeography of the Oenanthe hispanica–pleschanka–cypriaca complex (Aves, Muscicapidae: Saxicolinae): Diversification history of open-habitat specialists based on climate niche models, genetic data, and morphometric data. J Zool Syst Evol Res. 2018;00:1–20. https://doi.org/10.1111/jzs.12206
Schweizer, Manuel, Vera M. Warmuth, Niloofar Alaei Kakhki, Mansour Aliabadian, Marc Förschler, Hadoram Shirihai, Phil Ewels, Joel Gruselius, Remi-André Olsen, Holger Schielzeth, Alexander Suh, and Reto Burri. 2019. Genome-Wide Evidence Supports Mitochondrial Relationships and Pervasive Parallel Phenotypic Evolution in Open-Habitat Chats. Molecular Phylogenetics and Evolution 106568.
In wheatears and related species (‘open-habitat chats’), molecular phylogenetics has led to a comprehensively revised understanding of species relationships and species diversity. Phylogenetic analyses have suggested that, in many cases, phenotypic similarities do not reflect species’ relationships, revealing traditionally defined genera as non-monophyletic. This led to the suggestion of pervasive parallel evolution of open-habitat chats’ plumage coloration and ecological phenotypes. However, to date, the molecular evidence for the phylogenetic relationships among open-habitat chats is mainly limited to mitochondrial DNA. Here, we assessed whether the mitochondrial relationships are supported by genome-wide data. To this end, we reconstructed the species tree among 14 open-habitat chat taxa using multi-species coalescent analyses based on ∼1’300 SNPs. Our results confirm previous ones based chiefly on mitochondrial DNA; notably the paraphyly of the Oenanthe lugens complex and the clustering of individual species formerly placed in the genera Cercomela and Myrmecocichla within Oenanthe. Since several variable morphological and ecological characteristics occur in multiple places across the open-habitat chat phylogeny, our study consolidates the evidence for pervasive parallel evolution in the plumage coloration and ecology of open-habitat chats.
What should we conclude, that leucorhoa, seebohmi etc are not valid taxa, simply variation of Oenanthe oenanthe ?