Geographic patterns of mtDNA and Z-linked sequence variation in the Common Chiffchaff and the ‘chiffchaff complex’

We are grateful to the University of Washington Burke Museum (UWBM), US National Museum of Natural History (USNM), National History Museum Belgrade (NHMBEO), State Darwin Museum (SDM), Zoological Museum of Moscow State University (MSUZM), Yale Peabody Museum (YPM), University of Minnesota Bell Museum (MMNH), Texas A&M University Biodiversity Research and Teaching Collections (TCWC), Staffan Bensch, Stephen Menzie and Nigel Odin for sample loans. This is publication number 1585 of the Biodiversity Research and Teaching Collections at Texas A&M University. Funding: This work was supported by FEDER funds through the COMPETE programme, POPH/QREN/FSE funds to S.V.D. and NORTE2020/PORTUGAL funds (NORTE-01-0145-FEDER-AGRIGEN) to R.J.L., by the Fundação para a Ciência e a Tecnologia/MEC to S.V.D. (FCOMP-01-0124-FEDER-008941; PTDC/BIA- BEC/103435/2008) and R.J.L (SFRH/BPD/84141/2012), by the National Geographic Society to S.V.D, by Torino University Grant ex 60% 2017 and 2018 to M. P. and by Ministarstvo Kulture I Informisanja Republike Srbije (Project: Ptice zapadnog palearktika) to M.R. The Russian Science Foundation grant No. 14-50-00029 'Scientific basis of the national biobank – depository of living systems' (to E.A.K). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. The Russian Science Foundation grant No. 14-50-00029 'Scientific basis of the national biobank – depository of living systems' (to E.A.K).Peer reviewedPublisher PD

Effects of asymmetric nuclear introgression, introgressive mitochondrial sweep, and purifying selection on phylogenetic reconstruction and divergence estimates in the pacific clade of Locustella Warblers

When isolated but reproductively compatible populations expand geographically and meet, simulations predict asymmetric introgression of neutral loci from a local to invading taxon. Genetic introgression may affect phylogenetic reconstruction by obscuring topology and divergence estimates. We combined phylogenetic analysis of sequences from one mtDNA and 12 nuDNA loci with analysis of gene flow among 5 species of Pacific Locustella warblers to test for presence of genetic introgression and its effects on tree topology and divergence estimates. Our data showed that nuDNA introgression was substantial and asymmetrical among all members of superspecies groups whereas mtDNA showed no introgression except a single species pair where the invader's mtDNA was swept by mtDNA of the local species. This introgressive sweep of mtDNA had the opposite direction of the nuDNA introgression and resulted in the paraphyly of the local species' mtDNA haplotypes with respect to those of the invader. he multilocus nuDNA species tree resolved all interand intraspecific relationships despite substantial introgression. However, the node ages on the species tree may be underestimated as suggested by the differences in node age estimates based on non-introgressing mtDNA and introgressing nuDNA. In turn, the introgressive sweep and strong purifying selection appear to elongate internal branches in the mtDNA gene tree

Species ranges, sampling regions, localities and sample sizes for fasciolata species group (a: dark range white circles = <i>amnicola</i>, light range dark gray circles = <i>fasciolata</i>) and certhiola species group (b: light gray range with dark gray circles = <i>certhiola</i>, dark gray range with white circles = <i>ochotensis</i>, black range with black circles = <i>pleskei</i>).

<p>* indicates samples for which only mtDNA ND2 gene sequence data were available.</p

Phylogenetic tree based on MtDNA ND2 haplotypes (a) and multilocus species tree based on nuclear introns (b).

<p>Numbers next to branches indicate their posterior probability. The hyphenated numbers next to nodes identify the mode of their ages (middle number) and 95% HPD intervals (lower in front and higher after the mode). The time scale below each tree and node ages are in million years (Ma) before present.</p