Mitochondrial DNA reveals a strong phylogeographic structure in the badger across Eurasia

Abstract

The badger, Meles meles, is a widely distributed mustelid in Eurasia and shows large geographic variability in morphological characters whose evolutionary significance is unclear and needs to be contrasted with molecular data. We sequenced 512 bp of the mitochondrial DNA control region in 115 Eurasian badgers from 21 countries in order to test for the existence of structuring in their phylogeography, to describe the genetic relationships among their populations across its widespread geographic range, and to infer demographic and biogeographic processes. We found that the Eurasian badger is divided into four groups regarding their mitochondrial DNA: Europe, Southwest Asia, North and East Asia, and Japan. This result suggests that the separation of badgers into phylogeographic groups was influenced by cold Pleistocene glacial stages and permafrost boundaries in Eurasia, and by geographic barriers, such as mountains and deserts. Genetic variation within phylogeographic groups based on distances assuming the Tamura-Nei model with rate heterogeneity and invariable sites (d(T-N) range: 3.3-4.2) was much lower than among them (d(T-N) range: 10.7-38.0), and 80% of the variation could be attributed to differences among regions. Spatial analysis of molecular variance (samova), median-joining network, and Mantel test did not detect genetic structuring within any of the phylogeographic groups with the exception of Europe, where 50% of variation was explained by differences among groups of populations. Our data suggest that the European, Southwest Asian, and North and East Asian badgers evolved separately since the end of Pliocene, at the beginnings of glacial ages, whereas Japanese badgers separated from continental Asian badgers during the middle Pleistocene. Endangered badgers from Crete Island, classified as Meles meles arcalus subspecies, were closely related to badgers from Southwest Asia. We also detected sudden demographic growth in European and Southwest Asian badgers that occurred during the Middle Pleistocene.

Identification and Molecular Variations of CAN-SINEs from theZFYGene Final Intron of the Eurasian Badgers (GenusMeles)

“…It means that the molecular differentiation of the CAN-SINE in the ZFY final intron corresponds with the morphological differentiation of the Eurasian badgers classified into the four groups: the classification recently proposed by Del Cerro et al (2010) using an agreement with molecular phylogeny. In addition, the SINE lineages were in agreement with those of mtDNA (Marmi et al 2006;Del Cerro et al 2010;Tashima et al 2011). Yamada and Masuda (2010) reported that the CAN-SINE sequence was inserted to the ZFY final intron independently to the Japanese badger and the ermine, after diversification of at least nine Asian mustelid species.…”

“…Based on the mitochondrial DNA (mtDNA) cytochrome b phylogenetic analysis, Kurose et al (2001) reported the clear genetic distinction between the Japanese badgers and the Eurasian continental badgers. In addition, Marmi et al (2006) showed the four mtDNA lineages in the Eurasian badgers: Europe, Southwest Asia, North & East Asia, and Japan. Puzachenko (2005, 2006) canescens for the Southwest Asian badger, in addition to the previous three species.…”

Phylogeography of the weasel (Mustela nivalis) in the western-Palaearctic region: combined effects of glacial events and human movements

“…For M. erminea, low genetic differentiation and structure were observed among continental Eurasian populations, with only one lineage from Europe (Ireland excepted) to Japan up to Alaska whose origin is not specified (Fleming and Cook, 2002;Kurose et al, 2000Kurose et al, , 2005Martinkova et al, 2007). Finally, the phylogeographical analysis of Meles meles across Eurasia (Marmi et al, 2006) evidenced four genetic groups, but only one lineage in Europe possibly resulting from postglacial recolonization from several refugia.…”

Revisiting the phylogeography and demography of European badgers (Meles meles) based on broad sampling, multiple markers and simulations

“…Indeed, badger densities declined in some European countries owing to the large-scale gassing of setts during the rabies control campaigns of the 1960s and 1970s (Griffith and Thomas, 1997). Consequently, a number of studies have attempted to describe the genetic variation of the species in a European context (Marmi et al, 2006;Pope et al, 2006;O'Meara et al, 2012). However, they were essentially based on the same data set of samples from western and north-central Europe, with little to no sampling from eastern Europe and Italy, making it difficult to draw robust conclusions about the location of refugia, patterns of postglacial expansion and recent demography.…”