Search results for "Ogre"
showing 10 items of 2140 documents
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…
Spreading introgression in the wake of a moving contact zone
2006
An increasing number of studies describe moving hybrid zones. This raises the issue of their actual frequency and emphasizes the need for methods that enable the detection of zone movements without historical records. Asymmetric introgression, usually considered as a signature of geographical shift, might be misleading when applied to mitochondrial or potentially non-neutral markers. We investigated mitochondrial and genomic introgression, using 30 AFLP derived markers, in a well-documented moving avian contact zone between two warblers. We found no instances of cross-species transmission of mitochondrial DNA but we detected nuclear introgression. Introgression levels were higher in the exp…
When morphometry meets genetics: inferring the phylogeography of Carabus solieri using Fourier analyses of pronotum and male genitalia
2004
Population differentiation is a crucial step in the speciation process and is therefore a central subject in studies of microevolution. Assessing divergence and inferring its dynamics in space and time generally require a wide array of markers. Until now however, most studies of population structure are based on molecular markers and those concerning morphological traits are more scarce. In the present work, we studied morphological differentiation among populations of the ground beetle Carabus solieri, and tested its congruence with genetic population structure. The shape of pronotum and aedeagus was assessed using Dual Axis Fourier Shape Analysis. manova on Fourier coefficients revealed h…
Exploring phylogeography and species limits in the Altai vole (Rodentia: Cricetidae)
2013
Natural hybridization between species is not a rare event. In arvicoline rodents, hybridization is known to occur in the wild and/or in captivity. In the Microtus arvalis group, cytogenetic studies revealed that there were two distinct chromosomal forms (2n = 46 but a different fundamental number of autosomes). These forms have been attributed to two cryptic species: the common (arvalis) and Altai (obscurus) voles. Recently, individuals with intermediate karyotypes (F1 and backcrosses) were discovered in central European Russia, and, for this reason, other studies have regarded obscurus and arvalis as conspecific. In the present study, to address the question of the species limits in the Al…
Fitness of backcross six of hybrids between transgenic oilseed rape (Brassica napus) and wild radish (Raphanus raphanistrum
2002
The process of introgression between a transgenic crop modified for better agronomic characters and a wild relative could lead potentially to increased weediness and adaptation to the environment of the wild species. However, the formation of hybrid and hybrid progeny could be associated with functional imbalance and low fitness, which reduces the risk of gene escape and establishment of the wild species in the field. Our work compares the fitness components of parents and different types of backcross in the sixth generation of hybrids between transgenic oilseed rape (Brassica napus, AACC, 2n = 38) resistant to the herbicide glufosinate and wild radish (Raphanus raphanistrum, RrRr, 2n = 18)…
On personality, energy metabolism and mtDNA introgression in bank voles
2014
Consistent interindividual differences in behaviour, or animal personality, are emerging as an important determinant of a wide range of life history traits and fitness. Individual behaviour, however, may be constrained by between-individual variability in energy metabolism and may become unstable owing to intrinsic and extrinsic stressors. Here we tested the relationship between personality and physiology using wild-caught bank voles, Myodes glareolus, that varied according to mtDNA type (original or introgressed from Myodes rutilus). Personality traits and their within-individual consistency were assessed using an open field test and basal metabolic rate (BMR) was measured in an open-flow …
Adaptive introgression from maize has facilitated the establishment of teosinte as a noxious weed in Europe
2020
Global trade has considerably accelerated biological invasions. The annual tropical teosintes, the closest wild relatives of maize, were recently reported as new agricultural weeds in two European countries, Spain and France. Their prompt settlement under climatic conditions differing drastically from that of their native range indicates rapid genetic evolution. We performed a phenotypic comparison of French and Mexican teosintes under European conditions and showed that only the former could complete their life cycle during maize cropping season. To test the hypothesis that crop-to-wild introgression triggered such rapid adaptation, we used single nucleotide polymorphisms to characterize p…
Southern and fluorescent in situ hybridization detect three RAPD-generated PCR products useful as introgression markers in Petunia
1999
Fluorescent in situ hybridization (FISH) was used to reveal the intrachromosomal organization of 11 RAPD markers localized on the genetic map of Petunia hybrida. The cloned RAPD markers were analyzed by means of Southern hybridization to determine their level of sequence repetition and their specificity in different Petunia species with 2n=14 and 18 chromosomes. The same probes were then used in FISH experiments. Most of the RAPD clones studied showed high sequence repetition and no species specificity. Moreover, FISH analysis showed that these probes could belong to multilocus families as evidenced by the multiple FISH signals dispersed throughout the genome and present on every chromosome…
Brown trout (Salmo trutta L.) high genetic diversity around the Tyrrhenian Sea as revealed by nuclear and mitochondrial markers
2018
The brown trout (Salmo trutta L.) is widely distributed all around Europe but its natural diversity is threatened by massive stocking with Atlantic domestic strains. Describing the remaining natural genetic diversity and the proportion of domestic hatchery strains in rivers is a prerequisite for smart conservation. The high genetic diversity of brown trout populations around the Tyrrhenian Sea is well known. Use of twelve microsatellites has allowed description of the natural genetic structure of populations and detection of the consequences of stocking. Mitochondrial DNA control region sequences and the LDH-C1* gene enabled placement of each population into one of the six mitochondrial and…
Introgression of mitochondrial DNA among Myodes voles: consequences for energetics?
2011
Abstract Background Introgression of mitochondrial DNA (mtDNA) is among the most frequently described cases of reticulate evolution. The tendency of mtDNA to cross interspecific barriers is somewhat counter-intuitive considering the key function of enzymes that it encodes in the oxidative-phosphorylation process, which could give rise to hybrid dysfunction. How mtDNA reticulation affects the evolution of metabolic functions is, however, uncertain. Here we investigated how morpho-physiological traits vary in natural populations of a common rodent (the bank vole, Myodes glareolus) and whether this variation could be associated with mtDNA introgression. First, we confirmed that M. glareolus ha…