Search for dissertations about: "G-matrix"

Showing result 1 - 5 of 6 swedish dissertations containing the word G-matrix.

2. 1. Population differentiation in Lythrum salicaria along a latitudinal gradient

   Author : Katarina Olsson; Jon Ågren; Susan Kalisz; Umeå universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; additive genetic variance; clinal variation; evolutionary constraints; G matrix; genetic correlation; natural selection; pollen limitation; population differentiation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Abstract : In this thesis, quantitative genetic approaches, common-garden experiments, and field studies were combined to examine patterns of population differentiation and the genetic architecture of characters of putative adaptive significance in the widely distributed perennial herb Lythrum salicaria. In this work, I (1) documented patterns of population differentiation in phenology, life-history, and morphology along latitudinal gradients at different geographical scales, (2) investigated the genetic architecture of phenology, flower morphology, and inflorescence size, and (3) combined estimates of phenotypic selection in the field with information on the genetic variance-covariance matrix (G) to examine potential constraints to adaptive evolution. READ MORE

4. 2. The Interplay Between Selection And Constraints On Adaptive Divergence And Phenotypic Evolution

   Author : Fabrice Eroukhmanoff; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Selection; Constraints; Adaptive Divergence; G-matrix; Gene Flow.; Speciation;

   Abstract : Under natural or sexual selection, individuals with advantageous traits or combinations of traits will be more successful than their peers at surviving and/or reproducing. Provided these traits are heritable, meaning that they have a genetic basis, the traits combinations which are selected for, will increase in frequency in the population. READ MORE

5. 3. Plant-Herbivore Interactions and Evolutionary Potential of Natural Arabidopsis lyrata Populations

   Author : Adriana Puentes; Jon Ågren; Jenny Hagenblad; Roosa Leimu Brown; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; plant defenses; leaf herbivory; floral herbivory; ontogeny; G-matrix; trade-offs; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik; Biology with specialization in Evolutionary Genetics; Biologi med inriktning mot evolutionär genetik;

   Abstract : In this thesis, I combined field, greenhouse and common-garden experiments to examine the ecological and evolutionary consequences of plant-herbivore interactions and the genetic architecture of fitness-related traits in the insect-pollinated, self-incompatible, perennial herb Arabidopsis lyrata. More specifically, I examined (1) whether damage to leaves and inflorescences affects plant fitness non-additively, (2) whether trichome production is associated with a cost in terms of reduced tolerance to leaf and inflorescence damage, (3) whether young plant resistance to a specialist insect herbivore varies among populations, and (4) whether the evolution of flowering time, floral display and rosette size is constrained by lack of genetic variation or by genetic correlations among traits. READ MORE

6. 4. Evolutionary dynamics of migration and breeding in wild birds: genetic architecture, sexual conflicts and evolutionary constraints

   Author : Maja Tarka; Biologiska institutionen; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; quantitative genetics; heritability; intralocus sexual conflict; antagonistic selection; QTL; G-matrix; wing length; arrival date; migration; geolocator; bird; Acrocephalus arundinaceus;

   Abstract : Our knowledge of the evolutionary potential of traits involved in different selective episodes, especially in natural populations, is still limited. This is true for questions such as the genetic basis and inheritance of traits, how natural and sexual selection acts on them, and how selective conflicts influence the evolutionary response to selection. READ MORE

7. 5. The genetic architecture of sexual dimorphism

   Author : Robert Griffin; Urban Friberg; Alexei Maklakov; Jon Ågren; Russell Bonduriansky; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Drosophila melanogaster; evolution; intralocus sexual conflict; sex chromosomes; sexually antagonistic selection; sexual dimorphism;

   Abstract : Phenotypic differences between the sexes evolve largely because selection favours a different complement of traits in either sex. Theory suggests that, despite its frequency, sexual dimorphism should be generally constrained from evolving because the sexes share much of their genome. READ MORE