Search for dissertations about: "founder event"

Showing result 1 - 5 of 10 swedish dissertations containing the words founder event.

  2. 1. Dispersal, inbreeding and fitness in natural populations

    Author : Bengt Hansson; MEMEG; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; immigration; inbreeding; inbreeding depression; heterozygosity; microsatellite; great reed warbler; bird; Djurekologi; Animal ecology; philopatry; heritability; founder event; dispersal; bottleneck;

    Abstract : To evaluate how inbreeding affects the viability of small populations, it is crucial to determine what constitutes a population (i.e., the number of breeders in local patches and the degree of dispersal), and also to estimate the reproductive consequences of philopatry and emigration. READ MORE

  4. 2. Breeding System Evolution and Pollination Success in the Wind-Pollinated Herb Plantago maritima

    Author : Emil Nilsson; Jon Ågren; Pia Mutikainen; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biology; Breeding system; mating system; gynodioecy; male sterility; reproductive output; self-compatibility; self-incompatibility; wind-pollination; founder event; genetic structure; Biologi; Biology; Biologi; ekologisk botanik; Ecological Botany;

    Abstract : In this thesis, I examined variation in sex expression and mating patterns in the sexually polymorphic, wind-pollinated herb Plantago maritima. With a combination of field studies, greenhouse experiments, and genetic analyses, I (a) examined factors influencing sex ratio variation in gynodioecious plants (in which hermaphrodites and females coexist), (b) discovered variation in breeding system, (c) investigated density-dependence of seed production, and (d) documented genetic variation within and among populations close to the northern range margin in Europe. READ MORE

  5. 3. Spatiotemporal Evolution of Neotropical Organisms: New Insights into an Old Riddle

    Author : Alexandre Antonelli; Göteborgs universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Neotropics; Biodiversity patterns; Speciation models; Andean uplift; K T Event; Biogeography; Phylogenetics; Molecular dating; Rubiaceae; Chloranthaceae; Campanulaceae; Tetrapods; Biological systematics;

    Abstract : Nowhere else on Earth are there so many species of plants and animals as in the Neotropical region. Yet, many questions remain concerning the causes underlying such outstanding diversification. READ MORE

  6. 4. Genomic and Molecular Aspects of Mature Human B Cells

    Author : Carl-Magnus Högerkorp; Institutionen för immunteknologi; []
    Keywords : MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; transplantation; Human; B-cell; Germinal center; Centroblast; serology; Immunology; onkologi; cancer; Cytologi; cancerology; oncology; Microarray; Cytology; Mantel cell lymphoma; Immunologi; serologi; Centrocyte;

    Abstract : This thesis covers aspects of the mature human B cell and its different guises on its way to become a fully differentiated antibody forming plasma cell (AFC), the key player in the humoral immune system. The understanding of the complex molecular mechanisms taking place in the B cell, as it first encounters antigen, enters the germinal center (GC) reaction, giving rise to memory cells and plasma cells, is not only of importance for the curious scientist, but will also benefit the understanding of B cells in disease. READ MORE

  7. 5. Causes and consequences of spatial genetic variation in two species of scleractinian coral in East Africa : Levels of genetic differentiation and intraspecific diversity of Pocillopora damicornis and Platygyra daedalea

    Author : Petra Souter; Mats Grahn; Bertil Borg; Karen Miller; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; population genetics; corals; Kenya; Tanzania; Functional Zoomorphology; funktionell morfologi;

    Abstract : The work presented in this thesis is a study of the spatial genetic structure of two species of scleractinian corals, Pocillopora damicornis and Platygyra daedalea. The overall objective was to investigate the current capacity of MPAs to preserve and restore coral reefs and to contribute information to improve management decisions. READ MORE