Insights into the molecular underpinnings and natural history of phenotypic and species evolution

We aim to obtain insights into the molecular bases and evolutionary history of convergent phenotypic evolution and speciation in a unique system of colour-polymorphic songbirds – wheatears of the Oenanthe hispanica complex. Making use of the natural laboratory provided by pervasive hybridization in this complex replicated in several geographic regions, we aim to:

• Identify genomic regions underpinning plumage coloration and reconstruct color evolutionary history.
• Determine genomic regions resisting gene flow in all hybrid zones that likely act as species barriers.
• Understand the role of mobile genetic elements and chromosome rearrangements in phenotypic evolution and speciation.

To infer the genetic variation underpinning convergent color evolution and species barriers in wheatears, we interrogate cutting-edge whole-genome sequence data of (1) the hispanica complex from populations all over the range and (2) nearly all species of wheatears. We identify genomic regions underpinning plumage coloration in the hispanica complex and species barriers by, respectively, leveraging phenotypic polymorphisms or admixture in hybrid zones. We then use the information contained in these genomic regions to reconstruct the evolutionary history of the trait they underpin.

Phylogenetic analyses of whole genomes of most wheatear species and close relatives suggest that convergent phenotypic evolution in these species involved incomplete sorting of ancestral variation, introgression, and novel mutations. This conclusion is supported by our work in the O. hispanica complex. By tracing the underlying genetic variation we showed that the throat color polymorphism found in three species is ancestral to the complex; black back coloration newly evolved in pied wheatear from where it introgressed into Cyprus wheatear; and convergent throat and back color evolution at genus level is not explained by the same variation and thus must be based on novel mutations.

• Manuel Schweizer
• Holger Schielzeth
• Alexander Suh
• Alexander Kirschel
• Niloofar Alaei Kakhki
• Tamer Albayrak
• Mansour Aliabadian
• Pavlos Andriopoulos
• Vasileios Bontzorlos
• Rauri Bowie
• José Luis Copete
• Egidio Fulco
• Jesus T. Garcia
• Zura Javakashvili
• Fumin Lei
• Yang Liu
• Nika Paposhvili
• Attila Sandor
• Hadoram Shirihai
• Petar Shurulinkov
• Sergey Sklyarenko
• Borut Stumberger
• Abulfaz Tagiyev
• Vera Voronova

• Schweizerischer Nationalfonds
• Deutsche Forschungsgemeinschaft (DFG)
• Basler Stiftung für biologische Forschung