Search results for "Genetic variability"
showing 10 items of 200 documents
Molecular phylogeography ofThymus herba-barona(Lamiaceae): Insight into the evolutionary history of the flora of the western Mediterranean islands
2011
Thymus herba-barona is endemic to Majorca, Corsica, and Sardinia. In order to gain insight into its evolutionary history, we examined the genetic diversity and phylogeography of the species using sequences of the trnT-trnL intergenic spacer from 106 individuals belonging to 15 populations. We detected high within-species genetic diversity and strong among- population differentiation, but no evidence for phylogeographic structure. A haplotype network supported the occurrence of three main clades, the ancestral one being geographically restricted to the Gennargentu massif in Sardinia, while the two derived ones were relatively widespread. Coalescent-based analyses indicated deep divergence ti…
Intensive Management and Natural Genetic Variation in Red Deer (Cervus elaphus)
2017
The current magnitude of big-game hunting has outpaced the natural growth of populations, making artificial breeding necessary to rapidly boost hunted populations. In this study, we evaluated if the rapid increase of red deer (Cervus elaphus) abundance, caused by the growing popularity of big-game hunting, has impacted the natural genetic diversity of the species. We compared several genetic diversity metrics between 37 fenced populations subject to intensive management and 21 wild free-ranging populations. We also included a historically protected population from a national park as a baseline for comparisons. Contrary to expectations, our results showed no significant differences in geneti…
Effects of habitat fragmentation on the genetic structure of the monophagous butterfly Polyommatus coridon along its northern range margin
2004
Population genetic patterns of species at their range margin have important implications for species conservation. We performed allozyme electrophoresis of 19 loci to investigate patterns of the genetic structure of 17 populations (538 individuals) of the butterfly Polyommatus coridon, a monophagous habitat specialist with a patchy distribution. The butterfly and its larval food plant Hippocrepis comosa reach their northern distribution margin in the study region (southern Lower Saxony, Germany). Butterfly population size increased with host plant population size. The genetic differentiation between populations was low but significant (FST = 0.013). No isolation-by-distance was found. Hiera…
Monuments Unveiled: Genetic Characterization of Large Old Chestnut (Castanea sativa Mill.) Trees Using Comparative Nuclear and Chloroplast DNA Analys…
2020
Large old trees are extraordinary organisms. They not only represent a historical, landscape and environmental heritage of inestimable value, but they also witness a long history of environmental changes and human interventions, and constitute an as yet poorly known reserve of genetic variability which can be considered a great resource for management programs of forest species. This is the first genetic study on Italian, large, old chestnut trees (Castanea sativa Mill.). Ninety-nine trees were surveyed and analysed. For each tree, more than one sample from canopy and root suckers was collected to test for the genetic integrity of the individuals. All samples were genotyped using nine nucle…
Lack of molluscan host diversity and the transmission of an emerging parasitic disease in Bolivia.
2001
Fasciolosis is a re-emerging parasitic disease that affects an increasing number of people in developing countries. The most severe endemic affects the Bolivian Altiplano, where the liver fluke (Fasciola hepatica) and its hermaphroditic snail host, Lymnaea truncatula, have been introduced from Europe. To achieve a better understanding of the epidemiological situation and the consequences of the colonization event of this invasive species, genetic analysis of Bolivian snail populations was needed. Here we compare the genetic diversity and population structure of snail samples from the Bolivian Altiplano with samples from the Old World at six polymorphic microsatellite loci. Whereas some vari…
Genetic relationships between Sicilian wild populations of Brassica analysed with RAPD markers
2001
Brassica comprises very variable species, both morphologically and genetically. Among these species, the Sicilian populations of Brassica sect. Brassica, species related to kale crops form a complex group. The genetic relationships among 15 populations occurring in Sicily and one from Calabria, representing the existing diversity, have been investigated using random amplified polymorphic DNA (RAPD) markers. This assay, carried out with 22 arbitrary primers, generated 236 polymorphic fragments, 21 of which were specific for single populations (mainly Brassica insularis, Brassica incana and Brassica macro-carpa). Jaccard's genetic distances were computed and the phylogenic tree was establishe…
The genome sequencing of an albino Western lowland gorilla reveals inbreeding in the wild
2013
This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License.-- et al.
Mitochondrial phylogeography of the edible dormouse (Glis glis) in the western Palearctic region
2010
International audience; This study describes in detail the phylogeoraphic pattern Of the edible dormouse (Glis glis) a European rodent With pronounced hibernating behavior We Used sequences of 831 base pairs of the mitochondrial DNA cytochrome-b gene from 130 edible dormice collected at 43 localities (throughout Its distribution. Our results reveal presence of 3 main haplogroups: Sicilian, South Italian (restricted to the Calabrian region) (a widespread lineage corresponding to all remaining western, central. and eastern European populations). Examination of paleontological data confirms refugial regions for G,Its in the 3 Mediterranean peninsulas, although overall low genetic diversity is …
Genetic variability in Peregrine falcon populations of the Western Palaearctic region
2018
We analyzed variation in ten polymorphic microsatellites and a portion of cytochrome b mitochondrial DNA in 4 populations of the Peregrine falcon (Falco peregrinus). living in northern and southern Italy. Spain and Czech Republic to assess species diversity in the poorly investigated Western Palearctic region. The Spanish population lives in the contact zone between F. peregrinus peregrinus and F. p. brookei. both the northern Italian and the Czech populations live within the range of F. p. peregrinus and the southern Italian is within the F. p. brookei. We added to our cytochrome b sequence dataset comprising 81 samples. previously published mitochondrial DNA sequences (n = 31) of English …
Genetic variation in the mechanisms of direct mutual interference in a parasitic wasp: consequences in terms of patch-time allocation
2004
Summary 1. Direct mutual interference between insect parasitoids has always been considered to have major consequences for the population dynamics of parasitoid‐host systems. Furthermore, patch time allocation has also always been presented as an important behavioural component that is closely involved in the demographic features of host‐ parasitoid interactions. 2. Based on a detailed analysis of within-patch interactions between Trissolcus basalis (Hymenoptera: Scelionidae) females, the present study aimed to understand accurately how direct mutual interference can influence patch time allocation in this species. 3. The genetic variation in the behavioural mechanisms involved in the inter…