Search results for "YB"

An exhaustive phylogeny of the combtooth blenny genus Salaria (Pisces, Blenniidae) shows introgressive hybridization and lack of reciprocal mtDNA mon…

2019

A comprehensive phylogeny of the genus Salaria based on mitochondrial and nuclear markers grouped the extant species of the genus in well-characterised marine and freshwater clades, thus rejecting the hypothesis of a polytypic origin of the freshwater Salaria populations and supporting the occurrence of a single invasion event of the inland waters by the genus. Based on both mitochondrial and nuclear DNA datasets, the Salaria species of the freshwater clade proved to be vicariant taxa originating from a common ancestor which could possibly spread throughout the circum-Mediterranean inland waters during the late Miocene Messinian salinity crisis, then experiencing a process of allopatric dif…

2017

Because they can form seasonal mixed-species groups during mating and maternal care, bats are exciting models for studying interspecific hybridization. Myotis myotis and M. blythii are genetically close and morphologically almost identical, but they differ in some aspects of their ecology and life-history traits. When they occur in sympatry, they often form large mixed maternity colonies, in which their relative abundance can vary across time due to a shift in the timing of parturition. For the first time, we used non-invasive genetic methods to assess the hybridization rate and colony composition in a maternity colony of M. myotis and M. blythii located in the French Alps. Bat guano was co…

Observations on midgut of Apis mellifera workers (Hymenoptera: Apoidea) under controlled acute exposures to a Bacillus thuringiensis-based biopestici…

2016

International audience; AbstractMorphostructural investigations have been carried out on Apis mellifera workers treated with single controlled acute exposures to a biopesticide containing Bacillus thuringiensis (Bt), to detect midgut changes until 96 h. Our findings show concentration-dependence of these changes, reflecting in different degrees on both mortality and behaviour. In particular, some midgut changes are also found 96 h after treatment. Our results show that the tested product does not affect survival at presumable environmental concentrations, so confirming the lesser toxicity of Bt-based biopesticides compared to other pesticides. However, in the light of the discovered long-te…

Is homoploid hybrid speciation that rare? An empiricist’s view

2017

Is homoploid hybrid speciation that rare? An empiricist’s view

POSTMATING ISOLATION ANALYSIS IN FOUNDER-FLUSH EXPERIMENTAL POPULATIONS OF DROSOPHILA PSEUDOOBSCURA.

1996

In this paper, we report a detailed analysis intended to detect postmating barriers in experimental populations of Drosophila pseudoobscura obtained through nine founderflush cycles. The number of offspring produced was determined in three consecutive generations of hybridization. It is found that the evolution of premating barriers, as shown by two of these populations, is not necessarily accompanied by the evolution of postmating ones. Under the founder-flush model of speciation proposed by Carson (1971), the first step in the speciation process is usually thought to be an incidental genetic change through founder effect affecting mating behavior so that sexual premating isolation evolves…

2020

Turtles, a speciose group consisting of more than 300 species, demonstrate karyotypes with diploid chromosome numbers ranging from 2n = 26 to 2n = 68. However, cytogenetic analyses have been conducted only to 1/3rd of the turtle species, often limited to conventional staining methods. In order to expand our knowledge of the karyotype evolution in turtles, we examined the topology of the (TTAGGG)n telomeric repeats and the rDNA loci by fluorescence in situ hybridization (FISH) on the karyotypes of two emydids: the Sicilian pond turtle, Emys trinacris, and the yellow-bellied slider, Trachemys scripta scripta (family Emydidae). Furthermore, AT-rich and GC-rich chromosome regions were detected …

Gene flow from an adaptively divergent source causes rescue through genetic and demographic factors in two wild populations of Trinidadian guppies

2016

Genetic rescue, an increase in population growth owing to the infusion of new alleles, can aid the persistence of small populations, but its use as a management tool is limited by a lack of empirical data geared towards predicting effects of gene flow on local adaptation and demography. Experimental translocations provide an ideal opportunity to monitor the demographic consequences of gene flow. In this study we take advantage of two experimental introductions of Trinidadian guppies to test the effects of gene flow on downstream native populations. We individually marked guppies from the native populations to monitor population dynamics for 3 months before and 26 months after gene flow. We …

Unravelling the scientific debate on how to address wolf-dog hybridization in Europe

2019

Anthropogenic hybridization is widely perceived as a threat to the conservation of biodiversity. Nevertheless, to date, relevant policy and management interventions are unresolved and highly convoluted. While this is due to the inherent complexity of the issue, we hereby hypothesize that a lack of agreement concerning management goals and approaches, within the scientific community, may explain the lack of social awareness on this phenomenon, and the absence of effective pressure on decision-makers. By focusing on wolf x dog hybridization in Europe, we hereby (a) assess the state of the art of issues on wolf x dog hybridization within the scientific community, (b) assess the conceptual base…

Karyotype variability and inter-population genomic differences in freshwater ostracods (Crustacea) showing geographical parthenogenesis

2018

Transitions from sexual to asexual reproduction are often associated with polyploidy and increased chromosomal plasticity in asexuals. We investigated chromosomes in the freshwater ostracod species Eucypris virens (Jurine, 1820), where sexual, asexual and mixed populations can be found. Our initial karyotyping of multiple populations from Europe and North Africa, both sexual and asexual, revealed a striking variability in chromosome numbers. This would suggest that chromosomal changes are likely to be accelerated in asexuals because the constraints of meiosis are removed. Hence, we employed comparative genomic hybridization (CGH) within and among sexual and asexual populations to get insigh…

A new hybrid in the genus <em>Anthyllis</em> (Loteae-Leguminosae) from the eastern Iberian Peninsula

2016

We describe a new nothotaxon for the genus Anthyllis (Loteae- Leguminosae), A. . currasii P.P. Ferrer, Roselló & Guara, as result of natural interbreeding between A. cytisoides (Lag.) Pau and A. lagascana Benedí. It has been located at Monte de La Cañada, in Paterna (Valencia, Spain). This new hybrid is compared morphologically with its parents and the rest of nothotaxa described hitherto for the genus in the Iberian Peninsula, analysing the main diagnostic characters. The existence of the nothotaxa A. . fortuita Guara & P.P. Ferrer and A. . currasii implies the creation of the new nothosubgenus Ternijovis P.P. Ferrer, Roselló & Guara. A map of the known and documented distribut…