Andreas Kiefer

Molecular species identification boosts bat diversity

The lack of obvious morphological differences between species impedes the identification of species in many groups of organisms. Meanwhile, DNA-based approaches are increasingly used to survey biological diversity. In this study we show that sequencing the mitochondrial protein-coding gene NADH dehydrogenase, subunit 1 (nd1) from 534 bats of the Western Palaearctic region corroborates the promise of DNA barcodes in two major respects. First, species described with classical taxonomic tools can be genetically identified with only a few exceptions. Second, substantial sequence divergence suggests an unexpected high number of undiscovered species.

High gene diversity at swarming sites suggest hot spots for gene flow in the endangered Bechstein's bat

Our study shows that endangered Bechsteinsbats utilise distinct habitats at differentstages of their reproductive cycle, a findingthat has implications how habitat should beselected for preservation. Using nuclear andmitochondrial microsatellite DNA markers wecompared gene diversity of Bechsteins batswithin breeding colonies and at potentialmating sites. Bechsteins bat is one of themost threatened European bat species. Duringsummer it depends largely on mature deciduousforests. Females exhibit strict natalphilopatry. They form demographicallyindependent breeding colonies comprisingmaternally closely related bats. Males aresolitary. Like other temperate bats,Bechsteins bats swarm at the end of summer infront of caves. Because the sexes meet there,such swarming sites are potentially importantfor gene flow. Our genetic analyses reveal thatswarming sites have greater mitochondrial DNAgene diversity than colonies. Furthermore,field data on the phenology and reproductivestatus of several hundred individuals suggestthat Bechsteins bats mate during swarming. Incombination our field and genetic data showthat swarming sites provide the opportunity forgene flow among bats originating from differentcolonies. Therefore, we suggest that swarmingsites should be strictly protected to maintainthe observed high levels of gene flow amongcolonies.

The role of swarming sites for maintaining gene flow in the brown long-eared bat (Plecotus auritus).

Bat-swarming sites where thousands of individuals meet in late summer were recently proposed as ‘hot spots’ for gene flow among populations. If, due to female philopatry, nursery colonies are genetically differentiated, and if males and females of different colonies meet at swarming sites, then we would expect lower differentiation of maternally inherited genetic markers among swarming sites and higher genetic diversity within. To test these predictions, we compared genetic variance from three swarming sites to 14 nursery colonies. We analysed biparentally (five nuclear and one sex-linked microsatellite loci) and maternally (mitochondrial D-loop, 550 bp) inherited molecular markers. Three mtDNA D-loop haplolineages that were strictly separated at nursery colonies were mixed at swarming sites. As predicted by the ‘extra colony-mating hypothesis’, genetic variance among swarming sites (VST) for the D-loop drastically decreased compared to the nursery population genetic variance (VPT) (31 and 60%, respectively), and genetic diversity increased at swarming sites. Relatedness was significant at nursery colonies but not at swarming sites, and colony relatedness of juveniles to females was positive but not so to males. This suggests a breakdown of colony borders at swarming sites. Although there is behavioural and physiological evidence for sexual interaction at swarming sites, this does not explain why mating continues throughout the winter. We therefore propose that autumn roaming bats meet at swarming sites across colonies to start mating and, in addition, to renew information about suitable hibernacula.

Conflicting molecular phylogenies of European long-eared bats (Plecotus) can be explained by cryptic diversity

Conflicting phylogenetic signals of two data sets that analyse different portions of the same molecule are unexpected and require an explanation. In the present paper we test whether (i) differential evolution of two mitochondrial genes or (ii) cryptic diversity can better explain conflicting results of two recently published molecular phylogenies on the same set of species of long-eared bats (genus Plecotus). We sequenced 1714bp of three mitochondrial regions (16S, ND1, and D-loop) of 35 Plecotus populations from 10 European countries. A likelihood ratio test revealed congruent phylogenetic signals of the three data partitions. Our phylogenetic analyses demonstrated that the existence of a previously undetected Plecotus lineage caused the incongruities of previous studies. This lineage is differentiated on the species level and lives in sympatry with its sister lineage, Plecotus auritus, in Switzerland and Northern Italy. A molecular clock indicates that all European Plecotus species are of mid or late Pliocene origin. Plecotus indet. was previously described as an intergrade between P. auritus and Plecotus austriacus since it shares morphological characters with both. It is currently known from elevations above 800 m a.s.l. in the Alps, the Dinarian Alps and the Pindos mountains in Greece. Since we could demonstrate that incongruities of two molecular analyses simply arose from the mis-identification of one lineage, we conclude that molecular phylogenetic analyses do not free systematists from a thorough inclusion of morphological and ecological data.

The shaping of genetic variation in edge‐of‐range populations under past and future climate change

With rates of climate change exceeding the rate at which many species are able to shift their range or adapt, it is important to understand how future changes are likely to affect biodiversity at all levels of organisation. Understanding past responses and extent of niche conservatism in climatic tolerance can help predict future consequences. We use an integrated approach to determine the genetic consequences of past and future climate changes on a bat species, Plecotus austriacus. Glacial refugia predicted by palaeo-modelling match those identified from analyses of extant genetic diversity and model-based inference of demographic history. Former refugial populations currently contain disproportionately high genetic diversity, but niche conservatism, shifts in suitable areas and barriers to migration mean that these hotspots of genetic diversity are under threat from future climate change. Evidence of population decline despite recent northward migration highlights the need to conserve leading-edge populations for spearheading future range shifts.

A New Species of Long-Eared Bat (Chiroptera, Vespertilionidae) from Sardinia (Italy)

We describe a new species of long-eared bat, genus Plecotus, from the island of Sardinia (Italy). The new species is clearly distinguishable from other European Plecotus species by its mitochondrial 16S rRNA gene (4.1–9.6% sequence divergence) as well as by a unique combination of morphological characters such as brownish colour of dorsal pelage, a relatively large thumb and thumb claw, an almost cylindrical form of the penis and the characteristic shape of the baculum. The most important morphological diagnostic character is a relatively long (≥ 18 mm) and wide (≥ 6 mm) tragus. The new species is currently known from three localities on Sardinia. In addition to the new species we discovered a lineage of P. auritus, which is substantially differentiated from continental P. auritus at subspecific level (1.2–2.7% of sequence divergence of the 16S rRNA gene). The existence of these two endemic bat taxa on Sardinia highlights the islands importance in the conservation of the European bat community.

Cracking the nut: geographical adjacency of sister taxa supports vicariance in a polytomic salamander clade in the absence of node support.

The urodelan genus Lyciasalamandra, which inhabits a relatively small area along the southern Turkish coast and some Aegean islands, provides an outstanding example of a diverse but phylogenetically unresolved taxon. Molecular trees contain a single basal polytomy that could be either soft or hard. We here use the information of nuclear (allozymes) and mitochondrial (fractions of the 16S rRNA and ATPase genes) datasets in combination with area relationships of lineages to resolve the phylogenetic relationships among Lyciasalamandra species in the absence of sufficient node support. We can show that neither random processes nor introgressive hybridization can be invoked to explain that the majority of pairs of sister taxa form geographically adjacent units and interpret that this pattern has been shaped by vicariant events. Topology discordance between mitochondrial and nuclear trees mainly refers to an affiliation of L. helverseni, a taxon restricted to the Karpathos archipelago, to the western-most and geographically proximate mainland taxon in the nuclear tree, while in the organelle tree it turns out to be the sister lineage to the geographically most distant eastern clade. As this discordance cannot be explained by long-branch attraction in either dataset we suppose that oversea dispersal may have accounted for a second colonization of the Karpathos archipelago. It may have initiated introgression and selection driven manifestation of alien eastern mitochondrial genomes on a western nuclear background. Our approach of testing for area relationships of sister taxa against the null hypothesis of random distribution of these taxa seems to be especially helpful in phylogenetic studies where traditional measures of phylogenetic branch support fail to reject the null hypothesis of a hard polytomy.

Interannual Fidelity to Roosting Habitat and Flight Paths by Female Western Barbastelle Bats

The roost area selection of reproductive female western barbastelles was examined throughout four study seasons (2004–2007) via radio-tracking and automated acoustic monitoring. We specifically analysed the spatial structure of the roosting habitat and roost fidelity including a flight path connecting the roosts. We radio-tracked 13 colony members to 46 natural roosts, mainly dead oaks with large pieces of loose bark. Simultaneous tracking of four pairs of females revealed the existence of subgroups and fission-fusion-behaviour in Barbastella barbastellus. The colony displayed fidelity to the roost area rather than to single roost trees, although some trees were reused in two or three study seasons. Bimodal activity patterns obtained from acoustic monitoring indicated that the flight path connecting two core roosting areas functioned as a commuting corridor.

A revision of population designation and geographic distribution of the Lycian Salamander Mertensiella luschani (Steindachner, 1891)

Abstract Nine subspecies of the viviparous Lycian Salamander Mertensiella luschani live along the coast of southwestern and southern Turkey and on some islands (e.g. Kastellorizon, Meis, Kekova, and Carpathos). The species is locally very common. We describe seven new localities and add precise co-ordinates for most known populations. Existing confusion in the literature regarding locality names is discussed. Two type localities are re-defined. The actual and potential distribution of the species is analysed from ecological data. The range of M. luschani is restricted to karstic limestone with precipitation exceeding 800 mm annual rainfall. Most localities are below 500 m a.s.l., with a maximum of up to 1340 m a.s.l. The typical habitat of the species is pine forest on northerly exposed slopes.

Distortion of symmetrical introgression in a hybrid zone: evidence for locus‐specific selection and uni‐directional range expansion

The fate of species integrity upon natural hybridization depends on the interaction between selection and dispersal. The relative significance of these processes may be studied in the initial phase of contact before selection and gene flow reach equilibrium. Here we study a hybrid zone of two salamander species, Lyciasalamandra antalyana and Lyciasalamandra billae, at the initial phase of hybridization. We quantify the degree and mode of introgression using nuclear and mtDNA markers. The hybrid zone can be characterized as an abrupt transition zone, the central hybrid zone being only c. 400 m, but introgressed genes were traced up to 3 km. Introgression was traced in both sexes but gene flow may be slightly male‐biased. Indirect evidence suggests that hybrid males are less viable than females. Introgression occurred at two levels: (1) locus‐specific selection led to different allelic introgression patterns independent of species, while (2) asymmetrical species‐level introgression occurred predominately from L. antalyana to L. billae due to range expansion of the former. This indicates that foreign genes can be incorporated into novel genomic environments, which in turn may contribute to the great diversity of morphological variants in Lyciasalamandra.