Genetic differentiation and phylogeography of gulls in the Larus cachinnans–fuscus group (Aves: Charadriiformes)

Abstract

We studied mitochondrial genetic differentiation among nine taxa of large gulls of the Larus cachinnans-fuscus group, which form part of the circumpolar Herring Gull complex. Our primary interest was to see if there were unrecognized gene flow barriers, to what extent mitochondrial genetic population structure conformed to current taxonomic boundaries, and what it might reveal about possible differences in population history. Sequences (430 nucleotides) of the hypervariable control region I (HVR-I) were obtained from 580 individuals and proved highly informative within this recently diverged group of birds. Contrary to current classification, a basal split was revealed between an Atlantic-Mediterranean clade (atlantis, michahellis, armenicus) and a NW Palearctic-Central Asian clade (cachinnans, barabensis, mongolicus, fuscus-group). There was almost no mitochondrial gene flow between these two groups, although they are in geographical contact in two areas (eastern North Atlantic, Black Sea). Within each of the two major groups, there was strong phylogeographic structure with gene flow barriers between some neighbouring taxa (e.g. cachinanns vs. barabensis), but also a case of poor genetic differentiation between phenotypically distinct forms (barabensis vs. heuglini). At the subspecies level, current taxonomy corresponded well to molecular genetic structure: over 80% of the molecular genetic variance was partitioned among six (groups of) taxa. This is in sharp contrast to previous studies using allozymes and amplified fragment length polymorphism (AFLP) markers, which seemed to indicate extensive nuclear gene flow. Within-taxon haplotype phylogenies and mismatch distributions revealed contrasting demographic histories: cachinnans (Ponto-Caspian region) and atlantis (NE Atlantic) represent ancient lineages with large long-term population sizes, inland forms stem from very recent colonization events (barabensis, mongolicus) or passed through a population bottleneck (armenicus).

Evidence of a highly complex phylogeographic structure on a specialist river bird species, the dipper (Cinclus cinclus)

“…(ii) In contrast, other birds displayed phylogeographic patterns congruent with the Mediterranean refuges hypothesis (Griswold and Baker, 2002;Liukkonen-Anttila et al, 2002;Kvist et al, 2004;Brito, 2005). (iii) Finally, Nordic and/or marine species displayed distinct patterns with refuges located more northward (Tiedemann et al, 2004;Ruokonen et al, 2005) and/or close to the Atlantic Ocean, the Mediterranean and Black Sea (Kidd and Friesen, 1998;Liebers et al, 2001;Moum and Arnason, 2001).…”

Extensive mitochondrial introgression in North American Great Black-backed Gulls (Larus marinus) from the American Herring Gull (Larus smithsonianus) with little nuclear DNA impact

“…We amplified a 391 base pair (bp) fragment of the HVR-I part of the control region using primers L15610 5 0 -TTACCCCCCCACAWCATCATGTGG-3 0 (designed for this study) and H519 (Liebers et al, 2001) or L15522 and H1816 (Sonsthagen et al, 2012). A 389-bp cyt b fragment was amplified using primers L14967, H15503 or H15938 (Pons et al, 2004 (Liebers et al, 2001).…”

Phylogeography of the southern skua complex—rapid colonization of the southern hemisphere during a glacial period and reticulate evolution

“…A 386 bp segment of the hypervariable region 1 in the mitochondrial control region (CR I) was amplified using a similar procedure as in Liebers et al (2001). In a first step a 2500-3000 bp long fragment which included the entire control region, the ND6 gene and a part of the 12S rRNA gene was amplified using primers H2 (5 0 -GCC ATC CTA CGC TCA ATC CCC AAC AA-3 0 ) and DDL-C (5 0 -CAC CGC CAA GTC CTT AGA GTT T-3 0 ) and the Expand Long template PCR system (Roche) followed by a 15 min digestion with ExoSap (Amersham).…”