Admixture and introgression obscure evolutionary patterns in lesser whitethroat complex (<i>Curruca</i><i>curruca</i>; Passeriformes; Aves)

Determining the limits of species is still a major area contention, particularly when diagnostic differentiating characters are subtle and there contradiction between morphological genetic data. The lesser whitethroat (LWT) complex Curruca curruca represents an interesting study system to address this issue. Here, we use phylogeny-, admixture- principal component analysis- (PCA-) based analyses on whole-genome sequence data parapatric LWT taxa C. c. curruca, halimodendri, zagrossiensis althaea investigate prevalence importance gene flow in geographical where evidence suggests clinal transition populations. results suggest that populations Zagros Mts may represent lineage historically diverged from topotypical two lineages later coming into secondary contact with extensive as result. There no hybrid zone or cline Mts. On other hand, for halimodendri. also show possible admixture complex, extralimital sampled area, but nature needs be evaluated larger set.