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Do severe genetic bottlenecks lead to greater reproductive failure? : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Zoology, University of Canterbury /Burrows, Ben Robert. January 2006 (has links)
Thesis (M. Sc.)--University of Canterbury, 2006. / Typescript (photocopy). Includes bibliographical references. Also available via the World Wide Web.
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Likelihood inference for parametric models of dispersal /Jones, Mary Beatrix. January 2000 (has links)
Thesis (Ph. D.)--University of Washington, 2000. / Vita. Includes bibliographical references (p. 142-147).
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Desenvolvimento de metodologia high-throughput para estudo populacional do mosquito Aedes aegypti e comparação de dados de genes mitocondriais /Spenassatto, Carine. January 2011 (has links)
Resumo: O Aedes aegypti, culicídeo de hábitos diurnos, é originário do continente africano e está globalmente distribuído pelos trópicos em associação com as populações humanas. É considerado de grande importância epidemiológica por ser o principal vetor dos quatro sorotipos do vírus da dengue e da febre amarela. Uma das primeiras detecções da presença do mosquito no Estado de São Paulo aconteceu na década de 80 na cidade de Santos. Atualmente não há disponível nenhuma vacina ou medicamento eficiente contra a dengue, assim o controle da doença está restrito ao controle do vetor. Uma das alternativas de controle e entendimento das relações vetor-patógeno-homem se baseiam no desenvolvimento de ferramentas moleculares que utilizam técnicas baseadas em PCR, as quais têm possibilitado o estudo genético das populações do Ae. aegypti. Em tais estudos, vários marcadores foram envolvidos, tais como os SNPs (Single Nucleotide Polymorphisms) e marcadores mitocondriais. Nós desenvolvemos ensaios utilizando metodologia TaqMan® para o estudo genético populacional de duas populações do mosquito Aedes aegypti de cidades portuárias do Estado de São Paulo, utilizando nove marcadores SNPs. Verificamos que esta metodologia é reprodutível, rápida, de baixo custo e eficiente para estudos em larga escala. Pela análise AMOVA encontramos uma baixa, mas significativa diferenciação genética entre as populações do estudo (FST = 0,0324; P < 0,01), e uma alta taxa de migrantes por geração (8,72 entre as populações 2007 e 5,39 entre as populações 2008), indicando fluxo gênico entre as populações. A análise implementada no software Structure 2.3.1, evidenciou a existência de três clusters baseados em semelhanças genotípicas, distribuídos em dois grupos, confirmando uma moderada estruturação populacional. Verificamos através da análise de fragmentos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Aedes aegypti, is a diurnal mosquito, originated from the African continent and is globally distributed through the tropics in association with human populations. It is considered of great epidemiological importance for being the main vector of the four serotypes of Dengue and Yellow Fever. One of the first detections of the presence of the mosquito in the State of São Paulo happened in the 80's, in the city of Santos. Currently there is no available vaccine or effective medicine against dengue fever, and disease control is restricted to vector control. An alternative to control and understanding of vectorpathogen- man relationships are based on the development of molecular tools that use PCR-based techniques, which have enabled the genetic study of populations of Ae. aegypti. In such studies, several markers were involved, such as SNPs (Single Nucleotide Polymorphisms) and mitochondrial ones. We have developed assays using TaqMan® methodology for population genetic studies of two populations of Aedes aegypti from the port cities of São Paulo, using nine SNPs markers. We found that this methodology is reproducible, fast, inexpensive and efficient for large-scale studies. AMOVA analysis found a low but significant genetic differentiation between the studied populations (FST = 0.0324, P <0.01), and a high rate of migrants per generation (8.72 among populations in 2007 and 5.39 among populations in 2008), indicating gene flow between populations. The analysis implemented in software Structure 2.3.1, revealed the existence of three clusters based on genotypic similarities, divided into two groups, confirming a moderate population structure. We verified through the analysis of the mitochondrial gene fragments NADH dehydrogenase subunit 4 (ND4) a high genetic differentiation between the two study populations (FST = 0.18034, P <0.01), and a rate of migrants per generation considered high... (Complete abstract click electronic access below) / Orientador: Paulo Eduardo Martins Ribolla / Coorientador: Karina dos Santos Paduan / Mestre
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Population genetics of the fish tapeworm Wenyonia virilis (Caryophyllidea: Caryophyllaeidae) and its fish host Synodontis schallJIRSOVÁ, Dagmar January 2017 (has links)
The presented thesis consists of three papers/manuscripts (one published, one under review, one manuscript) on population genetic aspects of a host-parasite model, caryophyllidean tapeworm Wenyonia virilis and mochokid catfish Synodontis schall, in recently separated drainage basins, Lake Turkana and the Nile River. Three main topics are addressed herein: (i) intra- and inter-population genetic variability in and among hosts and parasites, (ii) comprehensive assessment of host model taxonomic status using multiple approaches, (iii) comparison of parasite intraspecific phenotypic with population genetic pattern. Two different genetic markers were applied to address these topics mtDNA (coxI) and whole genome scanning method (AFLP).
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Studies on X-chromosome determined variation in human individuals and populationsKerr, Charles Baldwin January 1965 (has links)
No description available.
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Genetic Diversity and Conservation of Pseudophoenix (Arecaceae) in HispaniolaRodriguez, Rosa 17 June 2014 (has links)
The Caribbean genus Pseudophoenix (Arecaceae) has its center of taxonomic diversity in Hispaniola (Haiti and the Dominican Republic). Three species (P. ekmanii, P. lediniana, and P. vinifera) are restricted to this island. In this thesis I investigated the population genetic diversity and structure of Pseudophoenix using ten microsatellite loci. Results showed homozygote excess and high inbreeding coefficients in all populations across all polymorphic loci. Overall, there was high differentiation among populations. Results from the Bayesian and Neighbor Joining cluster analyses identified groups that were consistence with currently accepted species delimitation. We included the only known population of an undescribed morph from the Dominican Republic that has been suggested to represent a new species. Results from the cluster analyses suggested that this putative species is closely related to P. sargentii from Turk and Caicos. Our study provided insights pertinent to the conservation genetics and management of this genus in Hispaniola.
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Worldwide MHC class I and II diversity in humansQutob, Nouar January 2011 (has links)
No description available.
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Climbing Mount Probable: Mutation as a Cause of Nonrandomness in EvolutionStoltzfus, Arlin, Yampolsky, Lev Y. 02 September 2009 (has links)
The classic view of evolution as "shifting gene frequencies" in the Modern Synthesis literally means that evolution is the modulation of existing variation ("standing variation"), as opposed to a "new mutations" view of evolution as a 2-step process of mutational origin followed by acceptance-or-rejection (via selection and drift). The latter view has received renewed attention, yet its implications for evolutionary causation still are not widely understood. We review theoretical results showing that this conception of evolution allows for a role of mutation as a cause of nonrandomness, a role that could be important but has been misconceived and associated misleadingly with neutral evolution. Specifically, biases in the introduction of variation, including mutational biases, may impose predictable biases on evolution, with no necessary dependence on neutrality. As an example of how important such effects may be, we present a new analysis partitioning the variance in mean rates of amino acid replacement during human-chimpanzee divergence to components of codon mutation and amino acid exchangeability. The results indicate that mutational effects are not merely important but account for most of the variance explained. The challenge that such results pose for comparative genomics is to address mutational effects as a necessary part of any analysis of causal factors. To meet this challenge requires developing knowledge of mutation as a biological process, understanding how mutation imposes propensities on evolution, and applying methods of analysis that incorporate mutational effects.
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Genetic differentiation across multiple spatial scales of the Red Sea of the corals Stylophora pistillata and Pocillopora verrucosaMonroe, Alison 12 1900 (has links)
Observing populations at different spatial scales gives greater insight into the
specific processes driving genetic differentiation and population structure. Here we
determined population connectivity across multiple spatial scales in the Red Sea to
determine the population structures of two reef building corals Stylophora pistillata and
Pocillopora verrucosa. The Red sea is a 2,250 km long body of water with extremely
variable latitudinal environmental gradients. Mitochondrial and microsatellite markers
were used to determine distinct lineages and to look for genetic differentiation among
sampling sites. No distinctive population structure across the latitudinal gradient was
discovered within this study suggesting a phenotypic plasticity of both these species to
various environments. Stylophora pistillata displayed a heterogeneous distribution of
three distinct genetic populations on both a fine and large scale. Fst, Gst, and Dest were all
significant (p-value<0.05) and showed moderate genetic differentiation between all
sampling sites. However this seems to be byproduct of the heterogeneous distribution, as
no distinct genetic population breaks were found. Stylophora pistillata showed greater
population structure on a fine scale suggesting genetic selection based on fine scale
environmental variations. However, further environmental and oceanographic data is
needed to make more inferences on this structure at small spatial scales. This study
highlights the deficits of knowledge of both the Red Sea and coral plasticity in regards to
local environmental conditions.
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Population genetics and phylogeography of bobcats (Lynx rufus) using microsatellites and mitochondrial DNACroteau, Emily Katherine 01 January 2009 (has links) (PDF)
Bobcats (Lynx rufus) are generalist carnivores with an expansive range from southern Canada to northern Mexico, in which 11 - 12 subspecies have been described. Since European settlement, bobcat habitat has become increasingly fragmented due to urbanization and development of agricultural land. Presently, there is little information on the genetic structure of bobcat populations at large spatial scales. Furthermore, it is unknown whether the current isolation of bobcat populations is a historic feature or whether recent landscape alterations have disrupted dispersal among previously connected populations. To address these questions, microsatellite and mitochondrial DNA data were used for relatedness measurements, spatial autocorrelation examinations, Bayesian assignment testing and sequence analysis of bobcats across their range. These analyses showed that, within southern Illinois, females were closely related to one another and males tended to disperse from their natal area. On a regional scale, microsatellite data revealed several distinct genetic groups within the midwest, notably eastern and western bobcat populations. In contrast, mitochondrial DNA analyses resolved little differentiation among bobcat populations, elucidating two-three phylogeographic groups. Taken together, these data reveal that bobcats have not historically, experienced large barriers to dispersal. Rather, recent habitat alterations may be disrupting dispersal over large scales. Genetically defined groups are potential conservation units and should be used for regional management of bobcats.
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