Genetic consequences of the ice ages on nurseries of the bat Myotis myotis: a mitochondrial and nuclear survey

Abstract

Analyses of mitochondrial DNA (mtDNA) control region polymorphism and of variation at 10 nuclear microsatellite loci were used to investigate the mechanisms and genetic consequences of postglacial expansion of Myotis myotis in Europe. Initial sampling consisted of 480 bats genotyped in 24 nursery colonies arranged along a transect of approximately 3000 km. The phylogeographical survey based on mtDNA sequences revealed the existence of major genetic subdivisions across this area, with several suture zones between haplogroups. Such zones of secondary contact were found in the Alps and Rhodopes, whereas other potential barriers to gene flow, like the Pyrenees, did not coincide with genetic discontinuities. Areas of population admixture increased locally the genetic diversity of colonies, which confounded the northward decrease in nucleotide diversity predicted using classical models of postglacial range expansion. However, when analyses were restricted to a subset of 15 nurseries originating from a single presumed glacial refugium, mtDNA polymorphism did indeed support a northwards decrease in diversity. Populations were also highly structured (PhiST = 0.384). Conversely, the same subset of colonies showed no significant latitudinal decrease in microsatellite diversity and much less population structure (FST = 0.010), but pairwise genetic differentiation at these nuclear markers was strongly correlated with increasing geographical distance. Together, this evidence suggests that alleles carried via male bats have maintained enough nuclear gene flow to counteract the effects of recurrent bottlenecks generally associated with recolonization processes. As females are highly philopatric, we argue that the maternally transmitted mtDNA marker better reflects the situation of past, historical gene flow, whereas current levels of gene flow are better reflected by microsatellite markers.

Genetic structure and diversity of a rare woodland bat, Myotis bechsteinii: comparison of continental Europe and Britain

“…Levels of diversity are high, and are similar to more common Myotis species found in Europe, such as M. daubentonii (Smith et al 2011), M. nattereri (Rivers et al 2005), M. myotis (Ruedi and Castella 2003), M. mystacinus and M. brandtii (Bogdanowicz et al 2012). The use of numerous autumn swarming sites throughout their range is likely to play an important role in maintaining high genetic diversity as it is frequently observed behaviour in Myotis bats (Kerth et al 2003).…”

Recurrent replacement of mtDNA and cryptic hybridization between two sibling bat speciesMyotis myotisandMyotis blythii

“…(a) Sampling and DNA amplifications To investigate the degree of overlap between mitochondrial lineages in Europe, we extended the extensive sampling of M. myotis mtDNA control region sequences already available (see Ruedi & Castella 2003) with 7 samples of M. myotis from Greece and Bulgaria and with 21 samples of M. blythii from Spain, France, Italy, Bulgaria and Greece (table 1). Both species are known to live in sympatry in all these areas.…”

“…myotis Haplogroups were defined following Ruedi & Castella (2003). Figure 1 is a maximum parsimony network obtained with the program TCS v. 1.18 (Clement et al 2000), showing the relationships among 21 HVII sequences of M. blythii, 7 sequences of M. myotis from Greece, Bulgaria, Italy, France and Spain, 4 sequences of M. blythii from Kirghiztan and more than 460 previously published sequences of M. myotis (Castella et al 2001;Ruedi & Castella 2003). It shows that all 16 different haplotypes of European M. blythii are intermingled within those of M. myotis in the network and do not form a distinct cluster.…”

Mitochondrial DNA signatures at different spatial scales: from the effects of the Straits of Gibraltar to population structure in the meridional serotine bat (Eptesicus isabellinus)

“…Despite their ability to fly, they show relatively high levels of genetic structuring, probably related to their diversified social organization systems: for example, Myotis bechsteinii, Myotis myotis, Macroderma gigas and Mystacina tuberculata (Worthington Wilmer et al, 1999;Kerth et al, 2000;Lloyd, 2003;Ruedi and Castella, 2003). The exceptions are the few migratory species, whose populations are typically poorly subdivided for example, Tadarida brasiliensis and Pteropus sp.…”