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In this study, we report the genetic population structure of the Fire-bellied toad Bombina bombina in Brandenburg (East Germany) in the context of conservation. We analysed 298 samples originating from 11 populations in Brandenburg using mitochondrial control region sequences and six polymorphic microsatellite loci. For comparison, we included one population each from Poland and Ukraine into our analysis. Within Brandenburg, we detected a moderate variability in the mitochondrial control region (19 different haplotypes) and at microsatellite loci (9-12 alleles per locus). These polymorphisms revealed a clear population structure among toads in Brandenburg, despite a relatively high overall population density and the moderate size of single populations (100-2000 individuals). The overall genetic population structure is consistent with a postglacial colonization from South East-Europe and a subsequent population expansion. Based on genetic connectivity, we infer Management Units (MUs) as targets for conservation. Our genetic survey identified MUs, within which human infrastructure is currently preventing any genetic exchange. We also detect an unintentional translocation from South East to North West Brandenburg, presumably in the course of fish stocking activities. Provided suitable conservation measures are taken, Brandenburg should continue to harbor large populations of this critically endangered species.
Ex situ collections in botanic gardens have great potential in contributing to the conservation of rare plants. However, little is known about the effects of cultivation on the genetic diversity and fitness of garden populations, about genetic changes due to unconscious selection and potential adaptation to the artificial conditions. We compared the genetic variability and fitness of the rare, short-lived perennial Cynoglossum officinale from 12 botanic gardens and five natural populations in Germany. Genetic variability was assessed with eight nuclear microsatellites. Plants were grown in a common garden and performance was measured over 2 years. Mean genetic diversity was very similar in botanic garden and natural populations. However, four of the garden populations exhibited no genetic variability at all. Moreover, the genetic diversity of garden populations decreased with increasing duration of cultivation, indicating genetic drift. Plant performance from natural and garden populations in terms of growth, flowering and seed production was similar and in garden populations only seed mass was strongly related to genetic diversity. Several lines of evidence indicated genetic changes in garden populations in response to cultivation. Seed dormancy was strongly reduced in garden populations, and in response to nutrient addition garden plants increased the size of their main inflorescence, while wild plants increased the number of inflorescences. These changes could be maladaptive in nature and reduce the suitability of garden populations as a source for reintroductions. We suggest that botanic gardens should pay more attention to the problem of potential genetic changes in their plant collections.
African weakly-electric fishes (Mormyridae) are able to communicate through species-specific electric signals; this feature might have favoured the evolutionary radiation observed in this family (over 200 species) by acting as an effective pre-zygotic isolation mechanism. In the present study we used mitochondria((cytb) and nuclear (rps7, scn4aa) markers in order to reconstruct a species-phylogeny and identify species boundaries for the genus Campylomormyrus, by applying inference methods based on the multispecies coalescent model. Additionally, we employed 16 microsatellite markers, landmark-based morphometric measurements, and electro-physiological analyses as independent lines of evidence to the results obtained from the sequence data. The results show that groups that are morphologically different are also significantly divergent at the genetic level, whereas morphologically similar groups, displaying dissimilar electric signals, do not show enough genetic diversity to be considered separate species. Furthermore, the data confirm the presence of a yet undescribed species within the genus Campylomormyrus. (C) 2016 Elsevier Inc. All rights reserved.
Tyrant flycatchers (Aves: Tyrannidae) are endemic to the New World, and many species of this group are threatened or near-threatened at the global level. The aim of this study was to test the 18 microsatellite markers that have been published for other Tyrant flycatchers in the Strange-tailed Tyrant (Alectrurus risora) and the Sharp-tailed Tyrant (Culicivora caudacuta), two endemic species of southern South American grasslands that are classified as vulnerable. We also analyzed the usefulness of loci in relation to phylogenetic distance to the source species. Amplification success was high in both species (77 to 83%) and did not differ between the more closely and more distantly related species to the source species. Polymorphism success was also similar for both species, with 9 and 8 loci being polymorphic, respectively. An increased phylogenetic distance thus does not gradually lead to allelic or locus dropouts, implying that in Tyrant flycatchers, the published loci are useful independent of species relatedness.
Talitrids are semiterrestrial crustacean amphipods inhabiting sandy and rocky beaches; they generally show limited active dispersal over long distances. In this study we assessed levels of population genetic structure and variability in the talitrid amphipod Orchestia montagui, a species strictly associated to stranded decaying heaps of the seagrass Posidonia oceanica. The study is based on six populations (153 individuals) and covers five basins of the Mediterranean Sea (Tyrrhenian, Ionian, Adriatic, Western and Eastern basins). Samples were screened for polymorphisms at a fragment of the mitochondrial DNA (mtDNA) coding for the cytochrome oxidase subunit I gene (COI; 571 base pairs) and at eight microsatellite loci. MtDNA revealed a relatively homogeneous haplogroup, which clustered together the populations from the Western, Tyrrhenian and Eastern basins, but not the populations from the Adriatic and Ionian ones; microsatellites detected two clusters, one including the Adriatic and Ionian populations, the second grouping all the others. We found a weak geographic pattern in the genetic structuring of the species, with a lack of isolation by distance at either class of markers. Results are discussed in terms of probability of passive dispersal over long distances through heaps of seagrass.
Introduction: We examined patterns of genetic divergence in 26 Mediterranean populations of the semi-terrestrial beachflea Orchestia montagui using mitochondrial (cytochrome oxidase subunit I), microsatellite (eight loci) and allozymic data. The species typically forms large populations within heaps of dead seagrass leaves stranded on beaches at the waterfront. We adopted a hierarchical geographic sampling to unravel population structure in a species living at the sea-land transition and, hence, likely subjected to dramatically contrasting forces.
Results: Mitochondrial DNA showed historical phylogeographic breaks among Adriatic, Ionian and the remaining basins (Tyrrhenian, Western and Eastern Mediterranean Sea) likely caused by the geological and climatic changes of the Pleistocene. Microsatellites (and to a lesser extent allozymes) detected a further subdivision between and within the Western Mediterranean and the Tyrrhenian Sea due to present-day processes. A pattern of isolation by distance was not detected in any of the analyzed data set.
Conclusions: We conclude that the population structure of O. montagui is the result of the interplay of two contrasting forces that act on the species population genetic structure. On one hand, the species semi-terrestrial life style would tend to determine the onset of local differences. On the other hand, these differences are partially counter-balanced by passive movements of migrants via rafting on heaps of dead seagrass leaves across sites by sea surface currents. Approximate Bayesian Computations support dispersal at sea as prevalent over terrestrial regionalism.
Introduction: We examined patterns of genetic divergence in 26 Mediterranean populations of the semi-terrestrial beachflea Orchestia montagui using mitochondrial (cytochrome oxidase subunit I), microsatellite (eight loci) and allozymic data. The species typically forms large populations within heaps of dead seagrass leaves stranded on beaches at the waterfront. We adopted a hierarchical geographic sampling to unravel population structure in a species living at the sea-land transition and, hence, likely subjected to dramatically contrasting forces.
Results: Mitochondrial DNA showed historical phylogeographic breaks among Adriatic, Ionian and the remaining basins (Tyrrhenian, Western and Eastern Mediterranean Sea) likely caused by the geological and climatic changes of the Pleistocene. Microsatellites (and to a lesser extent allozymes) detected a further subdivision between and within the Western Mediterranean and the Tyrrhenian Sea due to present-day processes. A pattern of isolation by distance was not detected in any of the analyzed data set.
Conclusions: We conclude that the population structure of O. montagui is the result of the interplay of two contrasting forces that act on the species population genetic structure. On one hand, the species semi-terrestrial life style would tend to determine the onset of local differences. On the other hand, these differences are partially counter-balanced by passive movements of migrants via rafting on heaps of dead seagrass leaves across sites by sea surface currents. Approximate Bayesian Computations support dispersal at sea as prevalent over terrestrial regionalism.
Fourteen microsatellite markers were isolated and characterized for the endangered Visayan tarictic hornbill (Penelopides panini, Aves: Bucerotidae). In an analysis of 76 individuals, the number of alleles per locus varied from one to 12. Expected and observed heterozygosity ranged from 0.00 to 0.87 and from 0.00 to 0.89, respectively. All primers also amplify microsatellite loci in Luzon tarictic hornbill (Penelopides manillae), Mindanao tarictic hornbill (Penelopides affinis), the critically endangered Walden's hornbill (Aceros waldeni) and the near-threatened writhed hornbill (Aceros leucocephalus). Two loci which are monomorphic in P. panini were found polymorphic in at least one of the other species. These 14 new microsatellite markers specifically developed for two genera of Philippine hornbills, in combination with those already available for the hornbill genera Buceros and Bucorvus, comprise a reasonable number of loci to genetically analyse wild and captive populations of these and probably other related, often endangered hornbills.