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Background Population genetic diversity and structure are determined by past and current evolutionary processes, among which spatially limited dispersal, genetic drift, and shifts in species distribution boundaries have major effects. In most wildlife species, environmental modifications by humans often lead to contraction of species’ ranges and/or limit their dispersal by acting as environmental barriers. However, in species well adapted to anthropogenic habitat or open landscapes, human induced environmental changes may facilitate dispersal and range expansions. In this study, we analysed whether isolation by distance and deforestation, among other environmental features, promotes or restricts dispersal and expansion in stone marten (Martes foina) populations. Results We genotyped 298 martens from eight sites at twenty-two microsatellite loci to characterize the genetic variability, population structure and demographic history of stone martens in Poland. At the landscape scale, limited genetic differentiation between sites in a mosaic of urban, rural and forest habitats was mostly influenced by isolation by distance. Statistical clustering and multivariate analyses showed weak genetic structuring with two to four clusters and a high rate of gene flow between them. Stronger genetic differentiation was detected for one stone marten population (NE1) located inside a large forest complex. Genetic differentiation between this site and all others was 20% higher than between other sites separated by similar distances. The genetic uniqueness index of NE1 was also twofold higher than in other sites. Past demographic history analyses showed recent expansion of this species in north-eastern Poland. A decrease in genetic diversity from south to north, and MIGRAINE analyses indicated the direction of expansion of stone marten. Conclusions Our results showed that two processes, changes in species distribution boundaries and limited dispersal associated with landscape barriers, affect genetic diversity and structure in stone marten. Analysis of local barriers that reduced dispersal and large scale analyses of genetic structure and demographic history highlight the importance of isolation by distance and forest cover for the past colonization of central Europe by stone marten. This confirmed the hypothesis that human-landscape changes (deforestation) accelerated stone marten expansion, to which climate warming probably has also been contributing over the last few decades. Electronic supplementary material The online version of this article (10.1186/s12898-017-0156-6) contains supplementary material, which is available to authorized users.

Species that pass repeatedly through narrow population bottlenecks (

Publisher Summary The expression of phenotypic plasticity is widespread in insects. One of the most extraordinary and economically devastating examples of phenotypic plasticity is found in locusts. In contrast to typical grasshoppers, locust species express an extreme form of density-dependent phenotypic plasticity known as “phase polyphenism.” Environmental factors such as temperature, photoperiod, resource availability and population density, are known to affect the development of a myriad of phenotypic traits that have consequences for individual performance, ecology, life-history, fitness and subsequent evolution. Given their diversity of responses and amenability to experimental manipulation and rearing in the lab, insects continue to play an important role as model organisms in empirical analyses of the fundamental relationships between genotypes and phenotypes in animals. Critical conclusions and recommendations from the analysis of recent laboratory stocks, findings that are broadly applicable across taxa to any research program rearing organisms in the lab, are also given in the chapter.

In Colombia, the mosquito Ochlerotatus taeniorhynchus has been identified as an efficient vector of the epidemic-epi-zootic Venezuelan equine encephalitis virus. We evaluated the genetic variability and heterogeneity of this mosquito in Colombian populations using eight microsatellite DNA loci. Two hundred and ten mosquito specimens collected from seven populations of the Colombian Atlantic coast (San Bernardo del Viento, Coveñas, Carta-gena, Barranquilla, Ciénaga, Dibulla, and Riohacha) were analyzed. We found five polymorphic microsatellite loci, with 19 alleles giving 62.5% polymorphism; the mean number of alleles per locus was 3.8. The mean expected heterogeneity ranged from 0.568 to 0.660. Most of the polymorphic microsatellite loci were in Hardy-Wein-berg disequilibrium, due to both deficit and excess of heterozygotes. The Fst statistic gave a total value of 0.0369, reflecting low genetic differentiation among the populations and, as a consequence, a low degree of structuring among them, while gene flow was high (Nm = 6.52); these findings point to genetic homogeneity among these populations. There was no significant linkage disequilibrium between genotype pairs of the various populations. We concluded that this mosquito is distributed in local populations along the Colombian Atlantic coast; these findings will be useful for developing strategies for controlling this vector. © FUNPEC-RP.

Two anchovy forms identified from their external morphology and designated as 'Silver' and 'Blue' anchovies were captured in Mersin Bay (Eastern Mediterranean Sea). Silver anchovy seemed to inhabit shallower waters (9-77 m) than Blue anchovy (majority at depths of 69-111 m). Significant differences in body shape, which was analyzed through geometric morphometrics, and in otolith shape, examined using Fourier analysis, separated the two forms. Length polymorphisms at two intron and 9 microsatellite loci showed strong genetic differences between the two forms. Mersin-Bay Blue anchovy were genetically related to Engraulis encrasicolus from the Western Mediterranean Sea. Mersin-Bay Silver anchovy possessed an original genetic composition that distinguished them from both E. encrasicolus and Engraulis albidus at the two intron loci, while presenting affinities to E. albidus based on microsatellite markers. Mersin-Bay Silver anchovy were assigned to the latter species, of which they are considered as a geographically isolated population. This is the first record of E. albidus in the Levantine basin and confirmation of its presence in the Eastern Mediterranean Sea. These results have implications for the management of anchovy populations and their habitats. (C) 2014 Elsevier B.V. All rights reserved. TUBITAK (The Scientific and Technological Research Council of Turkey)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [1080566, 1076066, 107T154, 106G005]; TUBITAK National Post-Doctoral Research Scholarship ProgramTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK); SeaDataNet-EU [026212]; UPGRADE BlackSeaScene-EU [226592] We are grateful to Dr. Yaisel J. Borrell for sharing microsatellite genotype data, to Dr. Dominique Ponton (IRD), Drs. Fusun Ozer and Dr. Devrim Tezcan (IMS-METU) for their help and advice, to Serdar Sakinan and other scientists who obtained and identified the anchovy samples, to Cihan Ayanoglu (METU) for running the Minitab programme, and to Allison Kideys (IMS-METU) for copy-editing the manuscript. This work was financed by the TUBITAK (The Scientific and Technological Research Council of Turkey) projects: Small Pelagic Fishes (1080566), TARAL (1076066), TBAG (107T154) and KAMAG TURKHAYGEN-I (106G005). A.K. was supported by TUBITAK National Post-Doctoral Research Scholarship Program, SeaDataNet-EU FP6 (026212) and UPGRADE BlackSeaScene-EU FP7 (226592) projects.

Publisher summary : The expression of phenotypic plasticity is widespread in insects. One of the most extraordinary and economically devastating examples of phenotypic plasticity is found in locusts. In contrast to typical grasshoppers, locust species express an extreme form of density-dependent phenotypic plasticity known as "phase polyphenism." Environmental factors such as temperature, photoperiod, resource availability and population density, are known to affect the development of a myriad of phenotypic traits that have consequences for individual performance, ecology, life-history, fitness and subsequent evolution. Given their diversity of responses and amenability to experimental manipulation and rearing in the lab, insects continue to play an important role as model organisms in empirical analyses of the fundamental relationships between genotypes and phenotypes in animals. Critical conclusions and recommendations from the analysis of recent laboratory stocks, findings that are broadly applicable across taxa to any research program rearing organisms in the lab, are also given in the chapter

International audience; Knowledge about the phylogenetic history, genetic variation and ecological requirements of a species is important for its conservation and management. Unfortunately, for many species this information is lacking. Here we use multiple approaches (phylogenetics, population genetics and ecological modelling) to evaluate the evolutionary history and conservation status of Capra walie, an endangered flagship species of wild goat endemic to Ethiopia. The analysis of mitochondrial cytochrome b and Y-chromosome DNA sequences suggests that C. walie forms a monophyletic clade with Capra nubiana, but potentially has been isolated for up to 0.8 million years from this closely related species. Microsatellite DNA analyses show that C. walie has very low genetic variation (mean heterozygosity=0.35) compared with other endangered mammals. This reduced variation likely derives from a prolonged demographic decline and small effective population size. Ecological niche modelling using the bioclimatic features of habitats occupied by C. walie, suggests ecological differences between C. walie and C. nubiana, and identifies the areas most suitable for future reintroductions of C. walie. The genetic and bioclimatic data suggest that C. walie is distinct and requires immediate conservation actions including genetic monitoring and reintroductions to establish independent populations. This study illustrates how combining noninvasive sampling along with genetic and ecological (bioclimatic) approaches can help assess conservation status of poorly known species.

Contact: deter@supagro.inra.fr; International audience; Hantaviruses are among the main emerging infectious agents in Europe. Their mode of transmission in natura is still not well known. In particular, social features and behaviours could be crucial for understanding the persistence and the spread of hantaviruses in rodent populations. Here, we investigated the importance of kinclustering and dispersal in hantavirus transmission by combining a fine-scale spatiotemporal survey (4 km2) and a population genetics approach. Two specific host-hantavirus systems were identified and monitored: the bank vole Myodes, earlier Clethrionomys glareolus––Puumala virus and the common vole Microtus arvalis—Tula virus. Sex, age and landscape characteristics significantly influenced the spatial distribution of infections in voles. The absence of temporal stability in the spatial distributions of viruses suggested that dispersal is likely to play a role in virus propagation. Analysing vole kinship from microsatellite markers, we found that infected voles were more closely related to each other than non-infected ones. Winter kin-clustering, shared colonies within matrilineages or delayed dispersal could explain this pattern. These two last results hold, whatever the host-hantavirus system considered. This supports the roles of relatedness and dispersal as general features for hantavirus transmission.