Unravelling the invasion history of the Asian tiger mosquito in Europe

Multiple introductions are key features for the establishment and persistence of introduced species. However, little is known about the contribution of genetic admixture to the invasive potential of populations. To address this issue, we studied the recent invasion of the Asian tiger mosquito (Aedes albopictus) in Europe. Combining genome‐wide single nucleotide polymorphisms and historical knowledge using an approximate Bayesian computation framework, we reconstruct the colonization routes and establish the demographic dynamics of invasion. The colonization of Europe involved at least three independent introductions in Albania, North Italy and Central Italy that subsequently acted as dispersal centres throughout Europe. We show that the topology of human transportation networks shaped demographic histories with North Italy and Central Italy being the main dispersal centres in Europe. Introduction modalities conditioned the levels of genetic diversity in invading populations, and genetically diverse and admixed populations promoted more secondary introductions and have spread farther than single‐source invasions. This genomic study provides further crucial insights into a general understanding of the role of genetic diversity promoted by modern trade in driving biological invasions.     

Precise Gene Editing Preserves Hematopoietic Stem Cell Function following Transient p53-Mediated DNA Damage Response

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Speciation with gene flow: Evidence from a complex of alpine butterflies (Coenonympha,Satyridae)

Until complete reproductive isolation is achieved, the extent of differentiation between two diverging lineages is the result of a dynamic equilibrium between genetic isolation and mixing. This is especially true for hybrid taxa, for which the degree of isolation in regard to their parental species is decisive in their capacity to rise as a new and stable entity. In this work, we explored the past and current patterns of hybridization and divergence within a complex of closely related butterflies in the genus Coenonympha in which two alpine species, C. darwiniana and C. macromma, have been shown to result from hybridization between the also alpine C. gardetta and the lowland C. arcania. By testing alternative scenarios of divergence among species, we show that gene flow has been uninterrupted throughout the speciation process, although leading to different degrees of current genetic isolation between species in contact zones depending on the pair considered. Nonetheless, at broader geographic scale, analyses reveal a clear genetic differentiation between hybrid lineages and their parental species, pointing out to an advanced stage of the hybrid speciation process. Finally, the positive correlation observed between ecological divergence and genetic isolation among these butterflies suggests a potential role for ecological drivers during their speciation processes.     

Distribution dynamics of the Tnt1 retrotransposon in tobacco

Retrotransposons contribute significantly to the size, organization and genetic diversity of plant genomes. Although many retrotransposon families have been reported in plants, to this day, the tobacco Tnt1 retrotransposon remains one of the few elements for which active transposition has been shown. Demonstration that Tnt1 activation can be induced by stress has lent support to the hypothesis that, under adverse conditions, transposition can be an important source of genetic variability. Here, we compared the insertion site preference of a collection of newly transposed and pre-existing Tnt1 copies identified in plants regenerated from protoplasts or tissue culture. We find that newly transposed Tnt1 copies are targeted within or close to host gene coding sequences and that the distribution of pre-existing insertions does not vary significantly from this trend. Therefore, in spite of their potential to disrupt neighboring genes, insertions within or near CDS are not preferentially removed with age. Elimination of Tnt1 insertions within or near coding sequences may be relaxed due to the polyploid nature of the tobacco genome. Tnt1 insertions within or near CDS are thus better tolerated and can putatively contribute to the diversification of tobacco gene function. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Redescription and molecular characterisation of Allogastrocotyle bivaginalis Nasir & Fuentes Zambrano, 1983 (Monogenea: Gastrocotylidae) from Trachurus picturatus (Bowdich) (Perciformes: Carangidae) off the Algerian coast,Mediterranean Sea

Systematic Parasitology - Allogastrocotyle bivaginalis Nasir & Fuentes Zambrano, 1983, the sole species of Allogastrocotyle Nasir & Fuentes Zambrano, 1983, was described from...     

Passive acoustic monitoring predicts daily variation in North Atlantic right whale presence and relative abundance in Roseway Basin,Canada

North Atlantic right whale monitoring in Roseway Basin, Canada, is primarily based on short‐term (<14 d) visual surveys conducted during August–September. Variability in survey effort has been the biggest limiting factor to studying changes in the population's occurrence and habitat use. Such efforts could be enhanced considerably using passive acoustic monitoring (PAM). We sought to determine if variation in whale presence, relative abundance, demography, and/or behavior (estimated through visual surveys) could be explained by variation in three right whale call types in this habitat. A generalized linear model was fit to 23 d of concurrent PAM and visual monitoring during four summers within the Roseway Basin Right Whale Critical Habitat boundaries. The model revealed significant positive relationships between relative abundance, call counts and presence of surface‐active group behavior. PAM can refine daily right whale presence estimates. While visual observations (n = 23 d) implied a 40% decline in right whale presence during 2014–2015 relative to 2004–2005, PAM data (n = 211 d) showed right whales were present between 71%–85% of survey days throughout all years analyzed. We demonstrate that PAM is a useful tool to extend periods of right whale monitoring, especially in areas where visual monitoring efforts may be limited.