Aim In this paper we investigate the evolutionary history of the Eurasian green woodpecker (Picus viridis) using molecular markers. We specifically focus on the respective roles of Pleistocene climatic oscillations and geographical barriers in shaping the current population genetics within this species. In addition, we discuss the validity of current species and subspecies limits.Location Western Palaearctic: Europe to western Russia, and Africa north of the Sahara. MethodsWe sequenced two mitochondrial genes and five nuclear introns for 17 Eurasian green woodpeckers. Multilocus phylogenetic analyses were conducted using maximum likelihood and Bayesian algorithms. In addition, we sequenced a fragment of the cytochrome b gene (cyt b, 427 bp) and of the Z-linked BRM intron 15 for 113 and 85 individuals, respectively. The latter data set was analysed using population genetic methods. ResultsOur phylogenetic results support the monophyly of Picus viridis and suggest that this taxon comprises three allopatric/parapatric lineages distributed in North Africa, the Iberian Peninsula and Europe, respectively. The North African lineage split from the Iberian/European clade during the early Pleistocene (1.6-2.2 Ma). The divergence event between the Iberian and the European lineages occurred during the mid-Pleistocene (0.7-1.2 Ma). Our results also support a post-glacial range expansion of these two lineages from distinct refugia located in the Iberian Peninsula and possibly in eastern Europe or Anatolia, which led to the establishment of a secondary contact zone in southern France.Main conclusions Our results emphasize the crucial role of both Pleistocene climatic oscillations and geographical barriers (Strait of Gibraltar, Pyrenees chain) in shaping the current genetic structure of the Eurasian green woodpecker. Our molecular data, in combination with diagnosable plumage characters, suggest that the North African green woodpecker (Levaillant's woodpecker) merits species rank as Picus vaillantii (Malherbe, 1847). The two European lineages could be distinguished by molecular and phenotypic characters over most of their respective geographical ranges, but they locally exchange genes in southern France. Consequently, we prefer to treat them as subspecies (P. viridis viridis, P. viridis sharpei) pending further studies.

In this study we investigated the phylogenetics of the Eurasian treecreeper (Certhia familiaris), a forest passerine with a wide Palaearctic range including Corsica, using three mitochondrial genes and three nuclear introns, and its phylogeographic history using the COI gene. Our phylogenetic results, including eight of the ten sub-species currently recognized, support the monophyly of C. familiaris with respect to its Indo-Asian sister species C. hodgsoni. C. familiaris comprises two lineages that diverged during the mid-Pleistocene (c. 1 Myr): one palaeoendemic lineage has an allopatric range nowadays restricted to the Corsica island and the Caucasus region whereas the second one, more recent and widespread, is distributed over most of Eurasia and in northern China. The most likely scenario that may explain such a pattern is a double colonization of the western Palaearctic from the eastern range of the species. During the middle Pleistocene period, a first lineage expanded its range up into Europe but did not persist through glacial cycles except in Corsica and the Caucasus region. Later, during the upper Pleistocene, a second lineage began to diversify around 0.09 Myr, spreading towards the western Palaearctic from a unique refuge likely located in the eastern Palaearctic [correction added on 6 March 2015 after first online publication: 0.9 Myr amended to 0.09 Myr]. Apart from C. f. corsa, our results do not suggest any distinct evolutionary history for other sub-species previously described on morphological grounds in Europe. Our study highlights the important conservation value of the Corsican treecreeper and emphasizes the major role of mature pine forests in the evolution of endemic bird taxa in Corsica.

We investigated the evolutionary history of the spotted flycatcher Muscicapa striata, a long distance migratory passerine having a widespread range, using mitochondrial markers and nuclear introns. Our mitochondrial results reveal the existence of one insular lineage restricted to the western Mediterranean islands (Balearics, Corsica, Sardinia) and possibly to the Tyrrhenian coast of Italy that diverged from the mainland lineages around 1 Mya. Mitochondrial genetic distance between insular and mainland lineages is around 3.5%. Limited levels of shared nuclear alleles among insular and mainland populations further support the genetic distinctiveness of insular spotted flycatchers with respect to their mainland counterparts. Moreover, lack of mitochondrial haplotypes sharing between Balearic birds (M. s. balearica) and Corso-Sardinian birds (M. s. tyrrhenica) suggest the absence of recent matrilineal gene flow between these two insular subspecies. Accordingly, we suggest that insular spotted flycatchers could be treated as one polytypic species (Muscicapa tyrrhenica) that differs from M. striata in morphology, migration, mitochondrial and nuclear DNA and comprises two subspecies (the nominate and M. t. balearica) that diverged recently phenotypically and in mitochondrial DNA and but still share the same nuclear alleles.This study provides an interesting case-study illustrating the crucial role of western Mediterranean islands in the evolution of a passerine showing high dispersal capabilities. Our genetic results highlight the role of glacial refugia of these islands that allowed initial allopatric divergence of insular populations. We hypothesize that differences in migratory and breeding phenology may prevent any current gene flow between insular and mainland populations of the spotted flycatcher that temporarily share the same insular habitats during the spring migration.

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The Eurasian treecreeper (Certhia familiaris) comprises two mitochondrial lineages that diverged during the mid-Pleistocene. One paleoendemic lineage has an allopatric range currently restricted to the Island of Corsica and the Caucasus region, whereas the second one has a very large Eurasian range. Here we used microsatellites (N = 6) and mitochondrial DNA (COI) to assess the genetic structure of insular and mainland populations from Corsica, mainland France and Central Italy (N = 258) and the level of mitochondrial and nuclear gene flow among these populations. Concordant with the mtDNA signal, microsatellites results clearly demonstrate that the Corsican population (C. f. corsa) is strongly divergent from nearby mainland populations (C. f. macrodactyla). Microsatellite data also support significant divergence and low gene flow between the Central Italian and mainland French populations. Our results suggest low nuclear gene flow from the mainland into Corsica and no mitochondrial gene flow. Sporadic gene flow from the nearby mainland may explain the presence of continental nuclear alleles in the genome of 5% of sampled insular birds. Our study confirms the existence of an endemic Corsican treecreeper lineage with important conservation value. Our results also imply that Eurasian treecreepers from Central Italy constitute a distinct management unit.