Population genetic structure in a self-compatible hermaphroditic snail is driven by drift independently of its contemporary mating system.

Genetic drift, gene flow, and natural selection commonly influence population genetic diversity. In populations of self-compatible hermaphrodites, the mating system (e.g.

Ecological disturbance reduces genomic diversity across an Alpine whitefish adaptive radiation.

Genomic diversity is associated with the adaptive potential of a population and thereby impacts the extinction risk of a species during environmental change. However, empirical data on genomic diversity of populations before environmental perturbations are rare and hence our understanding of the impact of perturbation on diversity is often limited. We here assess genomic diversity utilising whole-genome resequencing data from all four species of the Lake Constance Alpine whitefish radiation.

Phylogenetic and biogeographic history of brook lampreys (: Petromyzontidae) in the river basins of the Adriatic Sea based on DNA barcode data.

The Adriatic brook lamprey, zanandreai Vladykov 1955, was described from northeastern Italy. Its distribution is thought to include left tributaries of the River Po and the river basins of the Adriatic Sea from the River Po to the River Isonzo/Soča in Italy, Switzerland and Slovenia. It also shows a geographically isolated distribution in the Potenza River on the Adriatic slope in Central Italy.

Patterns and drivers of killifish diversity in lowland Tanzania.

Temporary pools are seasonal wetland habitats with specifically adapted biota, including annual killifishes that survive habitat desiccation as diapausing eggs encased in dry sediment. To understand the patterns in the structure of assemblages and their potential in wetland conservation, we compared biodiversity components (alpha, beta, and gamma) between regions and estimated the role and sources of nestedness and turnover on their diversity. We sampled assemblages from 127 pools across seven local regions in lowland Eastern Tanzania over 2 years, using dip net and seine nets.

Rapid generation of ecologically relevant behavioral novelty in experimental cichlid hybrids.

The East African cichlid radiations are characterized by repeated and rapid diversification into many distinct species with different ecological specializations and by a history of hybridization events between nonsister species. Such hybridization might provide important fuel for adaptive radiation. Interspecific hybrids can have extreme trait values or novel trait combinations and such transgressive phenotypes may allow some hybrids to explore ecological niches neither of the parental species could tap into.

Rapid buildup of sympatric species diversity in Alpine whitefish.

Adaptive radiations in postglacial fish offer excellent settings to study the evolutionary mechanisms involved in the rapid buildup of sympatric species diversity from a single lineage. Here, we address this by exploring the genetic and ecological structure of the largest Alpine whitefish radiation known, that of Lakes Brienz and Thun, using microsatellite data of more than 2000 whitefish caught during extensive species-targeted and habitat-randomized fishing campaigns. We find six strongly genetically and ecologically differentiated species, four of which occur in both lakes, and one of which was previously unknown.

The effect of top-predator presence and phenotype on aquatic microbial communities.

The presence of predators can impact a variety of organisms within the ecosystem, including microorganisms. Because the effects of fish predators and their phenotypic differences on microbial communities have not received much attention, we tested how the presence/absence, genotype, and plasticity of the predatory three-spine stickleback () influence aquatic microbes in outdoor mesocosms. We reared lake and stream stickleback genotypes on contrasting food resources to adulthood, and then added them to aquatic mesocosm ecosystems to assess their impact on the planktonic bacterial community.

Managing cryptic biodiversity: Fine-scale intralacustrine speciation along a benthic gradient in Alpine whitefish ( spp.).

Whitefish ( spp.) are an important catch for many freshwater fisheries, particularly in Switzerland. In support of this, supplemental stocking of whitefish species is carried out, despite lacking complete knowledge of the extent, distribution and origin of whitefish diversity in these lakes, potentially threatening local endemics via artificial gene flow.