57 research outputs found
Structure of worldwide populations of Lasioderma serricorne (Coleoptera: Anobiidae) as revealed by amplified fragment length polymorphism profiles
The cigarette beetle Lasioderma serricorne through transportation affects the infestation of stored tobacco. Using amplified fragment length polymorphism (AFLP), DNA polymorphisms were assessed in 16 populations of L. serricorne collected from 15 countries. The dendrograms constructed from profile distance matrices revealed well-supported colony clusters. There was no clear clustering as a function of the geographic origin of the samples. The results suggest extensive insect dispersal among geographical regions due to movement of infested commodities worldwide. This first AFLP population study of a stored-product insect demonstrates the potential of AFLP for distinguishing L. serricorne population
Do riverine barriers, history or introgression shape the genetic structuring of a common shrew (Sorex araneus) population?
The common shrew (Sorex araneus) is subdivided into numerous chromosome races. The Valais and Cordon chromosome races meet and hybridize at a mountain river in Les Houches (French Alps). Significant genetic structuring was recently reported among populations found on the Valais side of this hybrid zone. In this paper, a phylogenetic analysis and partial Mantel tests are used to investigate the patterns and causes of this structuring. A total of 185 shrews were trapped at 12 localities. All individuals were typed for nine microsatellite loci. Although several mountain rivers are found in the study area, riverine barriers do not have a significant influence on gene flow. Partial Mantel tests show that our result is caused by the influence of the hybrid zone with the Cordon race. The geographical patterns of this structuring are discussed in the context of the contact zone, which appears to extend up to a group of two rivers. The glacier they originate from is known to have cut the Arve valley as recently as 1818. The recent history of this glacier, its moraine and possibly rivers, may therefore be linked to the history of this hybrid zone
A microsatellite study in the Łęgucki Młyn/Popielno hybrid zone reveals no genetic differentiation between two chromosome races of the common shrew (Sorex araneus)
This study investigated a chromosome hybrid zone between two chromosomal races of the common shrew (Sorex araneus). Gene flow and genetic structure of the hybrid zone, located in the northeast of Poland, were studied using seven polymorphic autosomal microsatellite loci (L9, L14, L33, L45, L67, L68, L97) and a Y-linked microsatellite locus (L8Y). Seventy-five animals (46 of the Łęgucki Młyn race and 29 of the Popielno race) from nine different localities were examined and the data were analyzed using hierarchical AMOVA and F-statistic. The studied microsatellite loci and races (divided into nine geographical populations) were characterized by observed heterozygosity (HO), expected heterozygosities within (HS), and between (HT) populations, inbreeding coefficient (FIS), fixation index (FST), and average allelic richness (A). We found that genetic structuring within and between the two chromosome races were weak and non-significant. This finding and unconstrained gene flow between the races indicates a high level of migration within the Łęgucki Młyn/Popielno hybrid zone, suggesting that evolutionarily important genetic structuring does not occur in interracial zones where races which are not genetically distinct come into contact
Spatially Explicit Analysis of Metal Transfer to Biota: Influence of Soil Contamination and Landscape
Concepts and developments for a new field in ecotoxicology, referred to as “landscape ecotoxicology,” were proposed in the 1990s; however, to date, few studies have been developed in this emergent field. In fact, there is a strong interest in developing this area, both for renewing the concepts and tools used in ecotoxicology as well as for responding to practical issues, such as risk assessment. The aim of this study was to investigate the spatial heterogeneity of metal bioaccumulation in animals in order to identify the role of spatially explicit factors, such as landscape as well as total and extractable metal concentrations in soils. Over a smelter-impacted area, we studied the accumulation of trace metals (TMs: Cd, Pb and Zn) in invertebrates (the grove snail Cepaea sp and the glass snail Oxychilus draparnaudi) and vertebrates (the bank vole Myodes glareolus and the greater white-toothed shrew Crocidura russula). Total and CaCl2-extractable concentrations of TMs were measured in soils from woody patches where the animals were captured. TM concentrations in animals exhibited a high spatial heterogeneity. They increased with soil pollution and were better explained by total rather than CaCl2-extractable TM concentrations, except in Cepaea sp. TM levels in animals and their variations along the pollution gradient were modulated by the landscape, and this influence was species and metal specific. Median soil metal concentrations (predicted by universal kriging) were calculated in buffers of increasing size and were related to bioaccumulation. The spatial scale at which TM concentrations in animals and soils showed the strongest correlations varied between metals, species and landscapes. The potential underlying mechanisms of landscape influence (community functioning, behaviour, etc.) are discussed. Present results highlight the need for the further development of landscape ecotoxicology and multi-scale approaches, which would enhance our understanding of pollutant transfer and effects in ecosystems
A coleção fotográfica de Marcel Gautherot
Considering contemporary Anthropologys debate around photography, there is a\ud
keen interest in the understanding of one of the most important open to public consultation\ud
photographic collections on 20th Century Brazil, that of Frenchman Marcel Gautherot (1910-\ud
1996). The collection comprises around 25,000 photographs, purchased in 1999 by Instituto\ud
Moreira Salles and kept in its fund in the city of Rio de Janeiro. The text comments on the\ud
photographers work, linked to documentary projects under the patronage of institutions such as\ud
the Musée de l´Homme in Paris, at the end of the 1930s, and both the National Historic and\ud
Artistic Patrimony Service and the Brazilian Folklore Defence Campaign, in Brazil, between the\ud
years of 1940 -1960. Such commitments and interests define important thematic groupings in\ud
the production and organisation of his personal photographic archive. A discussion about criteria and technical procedures adopted by the photographer is attempted, detailing series\ud
and visual narratives about Brazilian cultures density. With the photographs purchase by the\ud
IMS, the oeuvres aesthetic quality, now as an institutional collection, is highlighted. The collections\ud
manners of preservation and conservation, reproduction and circulation are redefined
Effect of Trace and Toxic Elements of Different Brands of Cigarettes on the Essential Elemental Status of Irish Referent and Diabetic Mellitus Consumers
Estimation of toxic elements in the samples of different cigarettes and their effect on the essential elemental status in the biological samples of Irish smoker rheumatoid arthritis consumers
Phylogeographical structure, postglacial recolonization and barriers to gene flow in the distinctive Valais chromosome race of the common shrew (Sorex araneus).
Using one male-inherited and eight biparentally inherited microsatellite markers, we investigate the population genetic structure of the Valais chromosome race of the common shrew (Sorex araneus) in the Central Alps of Europe. Unexpectedly, the Y-chromosome microsatellite suggests nearly complete absence of male gene flow among populations from the St-Bernard and Simplon regions (Switzerland). Autosomal markers also show significant genetic structuring among these two geographical areas. Isolation by distance is significant and possible barriers to gene flow exist in the study area. Two different approaches are used to better understand the geographical patterns and the causes of this structuring. Using a principal component analysis for which testing procedure exists, and partial Mantel tests, we show that the St-Bernard pass does not represent a significant barrier to gene flow although it culminates at 2469 m, close to the highest altitudinal record for this species. Similar results are found for the Simplon pass, indicating that both passes represented potential postglacial recolonization routes into Switzerland from Italian refugia after the last Pleistocene glaciations. In contrast with the weak effect of these mountain passes, the Rhône valley lowlands significantly reduce gene flow in this species. Natural obstacles (the large Rhône river) and unsuitable habitats (dry slopes) are both present in the valley. Moreover, anthropogenic changes to landscape structures are likely to have strongly reduced available habitats for this shrew in the lowlands, thereby promoting genetic differentiation of populations found on opposite sides of the Rhône valley
Alps, genes, and chromosomes: their role in the formation of species in the Sorex araneus group (Mammalia, Insectivora), as inferred from two hybrid zones.
During the Pleistocene glaciations, the Alps were an efficient barrier to gene flow between isolated populations, often leading to allopatric speciation. Afterwards, the Alps strongly influenced the post-glacial recolonization of Europe and represent a major suture zone between differentiated populations. Two hybrid zones in the Swiss and French Alps between genetically and chromosomally well-differentiated species-the Valais shrew, Sorex antinorii, and the common shrew, S. araneus-were studied karyotypically and by analyzing the distribution of seven microsatellite loci. In the center of the Haslital hybrid zone the two species coexist over a distance of 900 m. Hybrid karyotypes, among them the most complex known in Sorex, are rare. F-statistics based on microsatellite data revealed a strong heterozygote deficit only in the center of the zone, due to the sympatric distribution of the two species with little hybridization between them. Structuring within the species (both F(IS) and F(ST)) was low. An hierarchical analysis showed a high level of interspecific differentiation. Results were compared with those previously reported in another hybrid zone located at Les Houches in the French Alps. Genetic structuring within and between species was comparable in both hybrid zones, although chromosomal incompatibilities are more important in Haslital, where a linkage block of the race-specific chromosomes should additionally impede gene flow. Evidence for a more restricted gene flow in Haslital comes from the genetically intermediate hybrid karyotypes, whereas in Les Houches, hybrid karyotypes are genetically identical to individuals of the pure karyotypic races. Genic and chromosomal introgression was observed in Les Houches, but not in Haslital. The possible influence of a river, separating the two species at Les Houches, on gene flow is discussed
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