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Causes and consequences of variation in dispersal strategy in an Arctic migrantHarrison, Xavier January 2010 (has links)
Improving our understanding of the factors that shape the demography of populations now requires that we consider no event in isolation, and instead express current performance as a product of previous events and processes. Patterns of site choice and dispersal likely underpin a large proportion of the variation in reproductive success among individuals, but the consequences of dispersal decisions may only become apparent many months later at a separate stage of the annual cycle Only by studying the interactions among seasons can we determine how differences in annual routine translate into asymmetries in fitness, and subsequently apply this understanding to processes occurring at the population level. This thesis begins with a review of the phenomena known as carry-over effects (COEs; Chapter 2), where I find evidence to support their occurrence in a multitude of taxa and identify previously unconsidered drivers of carry-over effects that could potentially explain their widespread nature. The remainder of this thesis comprises empirical work using light-bellied Brent geese (Branta bernicla hrota) as a model system to study these processes. In Chapter 3 I show evidence of a COE in Brent geese mediated by body condition, but in addition demonstrate how the strength of this effect is moderated by downstream climatic conditions operating in a density-independent fashion. Chapter 4 describes the development of novel polymorphic microsatellite loci to be used in population genetic and parentage studies. In Chapter 5 I show that light-bellied Brent geese are highly site faithful and that this fidelity has a cultural basis. Finally in Chapter 6 I characterize patterns of mate choice, and investigate potential consequences of this pattern in light of the observed site fidelity, in terms of risk of inbreeding. Collectively my results demonstrate the utility of combining long-term datasets with genetic pedigrees to investigate patterns of dispersal in a migratory species. Moreover they highlight the necessity to study individual performance in the context of the entire annual cycle in order to fully characterize the nature and strength of fitness determinants operating at multiple stages in a migratory species.
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Population genetic patterns in continuous environments in relation to conservation managementWennerström, Lovisa January 2016 (has links)
Genetic variation is a prerequisite for the viability and evolution of species. Information on population genetic patterns on spatial and temporal scales is therefore important for effective management and for protection of biodiversity. However, incorporation of genetics into management has been difficult, even though the need has been stressed for decades. In this thesis population genetic patterns in continuous environments are described, compared among species, and related to conservation management. The model systems are moose (Alces alces) in Sweden and multiple species in the Baltic Sea, with particular focus on the Northern pike (Esox lucius). The spatial scope of the studies is large, and much focus is dedicated towards comprehensive sampling over large geographic areas. The moose population in Sweden is shown to be divided into two major subpopulations, a northern and a southern one. Both subpopulations show genetic signals of major population bottlenecks, which coincide with known population reductions due to high hunting pressure (Paper I). The Northern pike in the Baltic Sea shows relatively weak, but temporally stable population genetic structure. An isolation by distance pattern suggests that gene flow primarily takes place among neighboring populations, either over shortest waterway distance or along the mainland coast, with island populations acting as stepping stones (Paper III). In a comparative study of seven Baltic Sea species no shared genetic patterns were found, either in terms of genetic divergence among or genetic diversity within geographic regions. These results complicate the incorporation of genetic data into management, because it suggests that no generalization can be made among species in the Baltic Sea, but that species-specific management is needed (Paper II). Over the last 50 years, 61 species in the Baltic Sea have been studied with respect to spatial genetic patterns. For over 20 of these species information of direct relevance for management is available. Relevant information is synthesized into management recommendations (Paper IV). This thesis provides vital information on spatial and temporal genetic structure for a number of ecologically and socio-economically important species. It shows that such information is important to consider species by species and that both local and metapopulation approaches are needed to effectively manage genetic diversity in e.g. moose and pike. Further, it identifies for which organisms in the Baltic Sea genetic information exists, how it can be used, and where important information is lacking. In order to successfully make use of genetic data in management, effective communication channels between academia and policy-makers are needed. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>
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Determinación de la Diversidad Genética de 172 accesiones de la colección nacional de Chenopodium quinoa Willd. “QUINUA” mediante marcadores microsatélitesVía y Rada Fernández, Romina Noelia January 2015 (has links)
El cultivo de Chenopodium quinoa “quinua" posee un alto potencial genético para contribuir con la seguridad alimentaria en países en vías de desarrollo, por esta razón se encuentra en proceso de revalorización. No obstante, la creciente demanda del cultivo ha centrado su interés en las variedades comerciales, descuidando las variedades nativas de la región andina, lo cual podría ocasionar la pérdida de diversidad. Por tal motivo, es necesaria la investigación de los ecotipos nativos así como su conservación en los bancos de germoplasma con la finalidad de describir la diversidad genética, elucidar la estructura de la población de quinua en nuestro país y dar a conocer el valor del germoplasma. En el presente trabajo se estimó la diversidad genética de los ecotipos de quinua procedentes de valles interandinos y altiplano mediante la genotipificación con 23 marcadores microsatélites mediante un sistema de PCR-Multiplex. Se detectaron 294 alelos en total con un promedio de 12.78 alelos por locus, siendo los ecotipos de valles interandinos los que presentaron un mayor número de alelos exclusivos (60 alelos), por lo tanto esta población presentó mayor riqueza alélica. Asimismo mediante un PCoA, se identificaron dos subpoblaciones de quinua con diferenciación genética moderada (Fst=0.059), las cuales guardaron relación con la procedencia de las muestras. Finalmente, se identificaron 10 marcadores altamente polimórficos los cuales permitirán la evaluación de la diversidad genética del germoplasma de quinua.Chenopodium quinoa “quinoa” has a high genetic potential to contribute to food security in developing countries, therefore it is in a valorization process. However, the growing demand has focused his interest in the cultivation of commercial varieties, neglecting the native varieties of the Andean region, which could lead to loss of diversity. Therefore, it is necessary the research of native ecotypes and its conservation in genebanks in order to describe the genetic diversity also elucidate the structure of the population of quinoa in our country and publicize the value of its germplasm. In this study the genetic diversity andean valleys and highland quinoa ecotypes was determined by genotyping 23 microsatellite markers using a PCR-Multiplex system. A total of 294 alleles were detected with an average of 12.78 alleles per locus, where the valleys ecotypes showed a greater number of private alleles (60 alleles), i.e. a higher allelic richness. In addition, using PCoA, two subpopulations of quinoa with moderate genetic differentiation (Fst = 0.059) were observed which were related to the origin of the samples. Finally, 10 highly polymorphic loci were identified, which will allow the evaluation of the genetic diversity of quinoa germplasm.
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Molekulární typizace izolátů z komplexu Arthroderma benhamiae, původce epidemické zoonotické dermatofytózy v Evropě / Molecular typization of isolates from Arthroderma benhamiae complex, a zoonotic agent of epidemic dermatophytosis in EuropeČmoková, Adéla January 2015 (has links)
Arthroderma benhamiae has been almost unknown among clinical mycologists but it is a cause of around 40 % of dermatophytic infections according to current studies in the Czech Republic. The species is primarily transmitted to humans from guinea pigs and other rodents. The epidemiological situation is similar in other countries in Central and Western Europe. The reason of significant increase in the incidence of infections has not been identified yet, and no sufficiently informative molecular markers have been developed for typification of the species that could help to resolve the cause of this problem. For the purposes of this study, isolates (n=268) from cases of human and animal dermatophytoses from the Czech Republic, Germany, Belgium, Switzerland, Italy, Japan and USA were selected. Ten variable microsatellite markers were developed and sequence analysis of two genetic loci (ITS rDNA and gpdh gene) were performed to reveal intraspecific variation. Phenotype was also studied at the level of micro- and macromorphology of the strains and growth parameters at several temperatures and on several cultivation media. Mating type idiomorph of each isolate was determined and mating experiments were performed by crossing pairs of genetically related as well as genetically distant strains. Sequence...
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Genetická struktura mediteránních populací kaloně Rousettus aegyptiacus / Genetická struktura mediteránních populací kaloně Rousettus aegyptiacusMarešová, Tereza January 2012 (has links)
5 Abstract The genus Rousettus represents the only fruit bat genus distributed both in Asia and Africa reaching northern distributional limits of the Pteropodidae family. This unusual distribution pattern is related to the ability of echolocation, subsequent cave dwelling and probably other thermoregulatory and behavioural adaptations to relatively cold and dry climate. Methods for identification of genetically discrete populations were used in the presented study to acquire better comprehension of historical ways of colonization along with current dispersal and migratory patterns of the Egyptian fruit bat (Rousettus aegyptiacus) in the Mediterranean basin and adjacent range patches. Modern approaches to population and landscape genetics were applied on a dataset comprising 553 individuals from 72 localities using 20 nuclear microsatellites. Our results revealed a significant genetic distance of East African individuals and certain substructure in the northern part of the range. Cypriot population is clearly separated, and - for higher K - the isolation of colonies from Egyptian oases is highly supported. Genetic proximity of south Arabian and Sinai populations contradict current taxonomy of the species. Our findings highlight the role of seas and deserts as barriers restricting gene flow and the evolution...
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Detailní taxonomická a klonální struktura druhového komplexu Daphnia longispina na podélném gradientu přehradní nádrže Želivka / Detailed taxonomic and clonal structure of the Daphnia longispina species complex on the longitudinal gradient of the Želivka ReservoirStodola, Jakub January 2013 (has links)
Canyon shaped reservoirs are characteristic by specific environmental horizontal gradients, so they enable existence of several species of the Daphnia longispina complex in one water body. Due to preference of distinct environmental conditions Daphnia species occurre in the different localities. The aim of my thesis was to analyze detail taxonomical and clonal structure of Daphnia longispina group by ten microsatellite markers on longitudinal gradient and compare it between two consecutive seasons. Simultaneously I received newly discovered divergent mitochondrial lineage from Želivka reservoir. It was confirmed, that the distribution of species and their hybrids in water reservoir was non-concidental and the taxonomic spatial distribution is in two consecutive seasons relatively constant. On the contrary the spatial and temporal distribution of clones was very heterogeneous. Clonal diversity in the interspecific hybrids was lower than in the coexisting parental species. This finding supports the hypothesis, that there exist reproductive barriers between parental genomes. Most of the clones were substantively variable, but several clones that occurred in both seasons in similar localities were found. It is possible that some clones are able of overwintering in hypolimnion and in the spring...
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Use of environmental variables to infer gene flow and population structure in the gopher tortoise (Gopherus polyphemus) and predict the seroprevalence of an emerging infectious diseaseClostio, Rachel Wallace 05 August 2010 (has links)
Understanding worldwide declines in reptiles due to factors such as habitat loss and emerging infectious disease has become an increasingly important focus in conservation biology. Here, I use novel approaches from the field of landscape genetics to combine spatial genetic data with landscape data at both regional and local spatial scales to explore natural and anthropogenic landscape features that shape population structure and gene flow in a federally threatened reptile, Gopherus polyphemus. I also utilize approaches from the field of spatial epidemiology to examine the extent to which environmental variables can be used to predict the seroprevalence of an associated pathogen Mycoplasma agassizzi in gopher tortoise populations. Using mitochondrial data, I find evidence of a historical barrier to gene flow that appears to coincide with the Apalachicola River. I also discover low genetic diversity and evidence of population bottlenecks in the western portion of the range. My evaluation at the regional scale shows that dispersal is limited by geographic distance, areas of low elevation and major roads ways. A finescale study reveals no evidence of spatial genetic structure within a 14 x 35 km area. However, soil type is significantly correlated with pairwise genetic distances between individuals, suggesting that this variable influences fine-scale population structure in the gopher tortoise. In addition to soil, high density canopy cover is an important factor impeding gene flow at the local level for females, while land cover type explains some of the genetic variance between males. Finally, temperature and precipitation appear to be important predictors of the seroprevalence of the pathogen Mycoplasma agassizii in gopher tortoises. The probability of an individual testing seropositive for exposure to this disease increased with high temperature and low precipitation values. The methods presented in this dissertation evaluate novel approaches for assessing the influence of environmental variables on population structure, dispersal and disease occurrence and could be applied in future studies of other threatened and endangered taxa.
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Molekulární charakterizace a hodnocení genetické diverzity genových zdrojů máku / Molecular characterization and evaluation of genetic diversity of genetic resources of poppy seedsSTARÁ, Martina January 2019 (has links)
The thesis deals with the study genetic diversity of poppies (Papaver somniferum L.) by SSR analysis. Altogether, 85 samples of poppies were evaluated. DNA was isolated from dried, mixed samples grown from seed using a modified CTAB method by Doyle and Doyle (1990). The seeds were provided by VÚO Opava. Six SSR primers were selected for the analysis and visualization was performed using chip electrophoresis. The PCR reaction was optimized with fluorescently labeled primer for fragmentation analysis. Chip electrophoresis was evaluated in MVSP using PCO analysis. The similarity matrix was further calculated and the samples showed hight genetic variability. The results of similarity matrix were provided to breeders as a basis for further breeding.
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Genetička struktura i filogeografski položaj vuka (Canis lupus L. 1758) Bosne i Hercegovine / Genetic structure and phylogeography of the wolf (Canis lupus L. 1758) from Bosnia and HerzegovinaŠnjegota Dragana 07 May 2019 (has links)
<p>Ovom tezom je obuhvaćena analiza genetičke strukture i filogeografskog položaja vuka (<em>Canis lupus L. </em>1758) na teritoriji Bosne i Hercegovine, na uzorku od ukupno 79 jedinki. Analize su sprovedene primjenom (i) 18 mikrosatelitskih lokusa nDNK pomoću kojih su detektovani: nivo genetičke varijabilnosti, populaciona struktura, prolazak populacije kroz genetičko usko grlo, te ukrštanje u srodstvu, i (ii) kontrolnog regiona (CR) regiona mtDNK pomoću kojih su sprovedene filogeografske analize. U radu je uočeno je grupisanje jedinki vuka Bosne i Hercegovine u dva genetička klastera što, s obzirom na slabu statističku podržanost, najvjerovatnije ukazuje na prisustvo strukture na većem nivou. Prethodno navedeno je detektovano analizama populacione strukture dijela dinarsko - balkanske populacije vuka,gdje je uočena distribucija vukova Bosne i Hercegovine i Srbije u odvojene genetičke klastere. Statistički značajni signali prolaska populacije vuka Bosne i Hercegovine kroz genetičko usko grlo u skorijoj prošlosti nisu detektovani. Sekvence kontrolnog regiona mtDNK vuka pokazale su se dovoljno informativnim za detekciju jedinstvenih haplotipova vuka Bosne i Hercegovine, za koje je uočena distribucija u dvije, prethodno u literaturi, detektovane haplogrupe bez jasnog alopatrijskog obrasca. Pored toga, analizama sekvenci dijela kontrolnog regiona mtDNK uzorka vuka Evrope, uočeno je da se demografska ekspanzija haplogrupe 2 desila mnogo ranije u prošlosti u odnosu na period ekspanzije haplogrupe 1, koji se poklapa sa periodom razdvajanja navedenih haplogrupa, prije oko 13000 godina, što ukazuje da je posljednji glacijalni maksimum imao uticaja u oblikovanju strukture genetičkih linija vuka u prošlosti. Rezultati dobijeni u ovom istraživanju su veoma informativni u cilju uspostavljanja pravilnog menadžmenta vrste i kreiranja plana zaštite vuka na nivou Bosne i Hercegovine, odnosno, na nivou dinarsko - balkanske populacije vuka iz koje se vrše rekolonizacije jedinki u susjedne populacije.</p> / <p>In this thesis, the genetic structure and phylogeography of the wolf (Canis L. 1758) in the territory of Bosnia and Hercegovina were analysed, from a total sample of 79 individuals. Analyses were conducted by applying (i) 18 microsatellite loci of nuclear DNA, by which we estimated: the level of genetic variability, population structure, kinship, bottleneck and inbreeding, and (ii) control region of mtDNA by which we analysed phylogeography. Two genetic clusters were observed for the wolf population from Bosnia and Hercegovina, although with statistically low support, which may point to structuring at the higher level. Indeed, after analysing the population structure at the higher, Dinaric - Balkan level, the distribution of wolves from Bosnia and Hercegovina and Serbia was observed as falling into two distinct genetic clusters. Statistically significant signs of the recent bottleneck were not observed in the wolf population from Bosnia and Hercegovina. Analyses of control region mtDNA were conducted with the aim of detecting haplotypes in the Bosnia and Hercegovina population, as well as in the European samples. Distribution of haplotypes into two haplogroups, described in previous literature, was observed, without a clear alopatric phylogeny pattern. Furthermore, the analyses of the same molecular marker showed that demographic expansion of haplogroup 2 occurred significantly earlier when compared to the demographic explosion of haplogroup 1 . Results from this study are extremely important for the creation of a management plan for wolves from Bosnia and Hercegovina, and at the higher Dinaric - Balkan level.</p>
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Seleção de marcadores moleculares em associação a características de interesse produtivo no tambaqui (Colossoma macropomum) /Ariede, Raquel Belini. January 2017 (has links)
Orientador: Diogo Teruo Hashimoto / Banca: Fabio Porto Foresti / Banca: Rafael Vilhena Reis Neto / Resumo: O Tambaqui (Colossoma macropomum), natural das bacias do rio Amazonas e do rio Orinoco, possui características favoráveis ao sistema de cultivo e boa aceitação de mercado. Contudo, há poucos estudos genéticos realizados com esta espécie, especialmente de melhoramento genético. Para a construção de um mapa genético desta espécie, é necessário o desenvolvimento de um elevado número de marcadores moleculares. Desta forma, este estudo teve como objetivo caracterizar microssatélites gene-associados e neutros (não gênicos), obtidos por Next Generation Sequencing (RNA-seq e Whole Genome Shotgun - WGS, respectivamente), para serem disponibilizados em estudos de associação com QTLs (Quantitative Trait Loci) e construção de um mapa genético. De modo geral, a avaliação de 200 marcadores (100 de cada conjunto) resultou em 45 loci polimórficos. Do conjunto de marcadores RNA-seq, as heterozigosidades observada e esperada (HO e HE) variaram de 0,09 a 0,73, e 0,09 a 0,85, respectivamente. Do conjunto WGS, HO e HE variaram de 0,33 a 0,95, e 0,28 a 0,92, respectivamente. Posteriormente, alguns microssatélites foram testados em três famílias de C. macropomum para buscar associações com características de resistência à bactéria e crescimento. Para o estudo de resistência, três famílias (n = 120), foram submetidas ao desafio bacteriano com Aeromonas hydrophila. Os dados do desafio apresentaram diferenças significativas nos tempos de morte e taxa de mortalidade entre as famílias. O crescimento foi... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Tambaqui (Colossoma macropomum), is a fish species of the Amazon and Orinoco rivers, with favorable traits to the production system and market acceptance. However, there are few genetic studies with this species, especially genetic improvement. For the construction of a genetic map of this species, the development of a high number of molecular markers is necessary. Thus, this study aimed to characterize gene-associated and neutral (non-gene) microsatellites obtained by Next Generation Sequencing (RNA-seq and Whole Genome Shotgun - WGS, respectively), to be available in association studies with Quantitative Trait Loci (QTLs) and construction of a genetic map. Overall, the evaluation of 200 markers (100 of each set) resulted in 45 polymorphic loci. In the RNA-seq data, the observed and expected heterozygosity (Ho and He) ranged from 0.09 to 0.73, and 0.09 to 0.85, respectively. In the WGS data, Ho and He ranged from 0.33 to 0.95, and 0.28 to 0.92, respectively. Subsequently, some microsatellites were tested in three families of C. macropomum to seek associations with bacterial resistance and growth characteristics. For the resistance study, three families (n = 120) were submitted to the bacterial challenge with Aeromonas hydrophila. The challenge data presented significant differences in time of death and mortality rate among the families. Growth was evaluated by morphometric measures and weight, and all the characteristics were significantly correlated (p < 0.01). Microsatelli... (Complete abstract click electronic access below) / Mestre
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