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51	Les causes des variations du taux d’évolution moléculaire entre lignées / The causes of molecular evolutionary rate variations among lineages Dos Santos Lourenço, João 08 December 2011 (has links) Cette thèse porte sur le décryptage des causes des variations des taux de substitution moléculaires entre lignées. D'un point de vue théorique, différentes hypothèses sont souvent basées sur des distributions des valeurs sélectives des mutations assez simplistes. En utilisant le modèle géométrique de Fisher, nous avons pu dériver des expressions pour cette distribution, et mettre en évidence l'importance de la complexité phénotypique et de la pléiotropie des mutations. Les variations entre espèces de la proportion de changements d'amino-acides qui sont adaptatifs sont souvent interprétées comme une conséquence de différences de taille de population. Par des simulations, nous avons démontré que la taille efficace des populations n'a qu'une influence faible sur la variation de ces taux, et que les changements environnementaux et la complexité phénotypique peuvent avoir un effet plus important. En ce qui concerne les taux de substitution synonymes, une relation inverse avec la masse corporelle est souvent décrite chez les vertébrés endothermes. Pour déterminer si cette relation est aussi valable chez les vertébrés ectothermes, nous avons suivi une approche comparative portant sur les tortues. Nous avons estimé les taux de substitution synonymes chez 224 espèces, que nous avons ensuite comparé à la masse corporelle (et autres traits d'histoire de vie) et à une variable environnementale (la latitude). Nos résultats démontrent que les taux d'évolution moléculaires sont fortement corrélés aux conditions environnementales et non pas à des traits d'histoire de vie. / The main objective of the present thesis is to elucidate the causes of variations in rates of molecular evolution among lineages, and in particular, to understand how factors connected to mutation, selection and genetic drift can influence these variations. Évolution moléculaire Taux de substitution Modèle géometrique de Fisher Adaptation Taille efficace des populations Molecular evolution Rates of substitution Fisher geometrical model Adaptation Effective population size
52	Neutrální genetická variabilita a struktura populací kamzíka horského na Slovensku / Neutral genetic variability and structure in chamois populations in Slovakia Hájková, Andrea January 2011 (has links) The Tatra chamois (Rupicapra rupicapra tatrica), an endemic mountain ungulate, occurs in the High Tatra Mts. (northern Slovakia and southern Poland). In the second part of the 20th century several chamois introductions occurred in Slovakia: Tatra chamois (from the High Tatra Mts.) were introduced into the Low Tatra Mts., while Alpine chamois (R. r. rupicapra) into the Veľká Fatra and Slovenský raj Mts. The High Tatra Mts. population underwent several population declines (bottlenecks) and all other Slovak populations were founded from only a few individuals (founder effect). Moreover, because the Low Tatra, Veľká Fatra and Slovenský raj are neighbouring mountain ranges, there is a potential risk of migration and hybridisation between the subspecies. Using 18 microsatellite loci, we studied neutral genetic variability, structure and potential hybridisation in chamois populations in Slovakia. The study is based on 193 samples: 95 tissue and 5 blood samples, and 88 faecal and 5 hair samples. Low genetic variability was found in all populations, the lowest one in High Tatra Mts. population. High values of fixation index, the number of private alleles, and factorial correspondence analysis indicated strong differentiation between the studied populations. Bayesian clustering divided Slovak chamois...
53	Consequences of Insect Flight Loss for Molecular Evolutionary Rates and Diversification Mitterboeck, T. Fatima 25 May 2012 (has links) This thesis investigates the molecular evolutionary and macroevolutionary consequences of flight loss in insects. Chapter 2 tests the hypothesis that flightless groups have smaller effective population sizes than related flighted groups, expected to result in a consistent pattern of increased non-synonymous to synonymous ratios in flightless lineages due to the greater effect of genetic drift in smaller populations. Chapter 3 tests the hypothesis that reduced dispersal and species-level traits such as range size associated with flightlessness increase extinction rates, which over the long term will counteract increased speciation rates in flightless lineages, leading to lower net diversification. The wide-spread loss of flight in insects has led to increased molecular evolutionary rates and is associated with decreased long-term net diversification. I demonstrate that the fundamental trait of dispersal ability has shaped two forms of diversity—molecular and species—in the largest group of animals, and that microevolutionary and macroevolutionary patterns do not necessarily mirror each other. / Generously funded by NSERC with a Canada Graduate Scholarship and the Government of Ontario with an Ontario Graduate Scholarship to T. Fatima Mitterboeck; NSERC with a Discovery Grant to Dr. Sarah J. Adamowicz evolution flight transitions insects molecular rates diversification flightless flight loss dispersal holometabola insect species species richness effective population size population size population subdivision macroevolution microevolution comparative method substitution rates dN/dS ratios non-synonymous substitutions nearly neutral theory molecular clock mitochondrial DNA nuclear DNA OXPHOS COI COX1 Cytochrome c oxidase subunit I pterygota speciation extinction whole-tree method sister-group method
54	Genomic Prediction for Quantitative Traits: Using Kernel Methods and Whole Genome Sequence Based Approaches / Genomische Vorhersage für quantitative Merkmale: Verwendung von Kernel-Methoden und Verfahren, die auf vollständigen Genomsequenzen basieren Ober, Ulrike 28 September 2012 (has links) No description available. 310 Statistik EJCD 100 EJCD 150 EJCD 250 EGC 070 EGCG 000 EGCF 000 EGCJ 000 YFH 000 WD 100 WD 200 WJ 100 WJV 000 Mathematics and Computer Science BLUP Kriging Matérn Kovarianzfunktion SNP genomische Vorhersage genetischer Wert Sequenzdaten Drosophila melanogaster komplexe Merkmale effektive Populationsgröße Linkage Disequilibrium BLUP Kriging Matérn covariance function SNP genomic prediction genetic value sequence data Drosophila melanogaster complex traits effective population size linkage disequilibrium 31.73 42.11 42.64 48.64 42.64 48.64

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