Search for dissertations about: "local genetic variation"

Showing result 1 - 5 of 108 swedish dissertations containing the words local genetic variation.

  1. 1. Advances in studying the role of genetic divergence and recombination in adaptation in non-model species

    Author : Ramprasad Neethiraj; Christopher Wheat; Sören Nylin; Mathieu Joron; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Recombination; Genetic divergence; Lepidoptera; Genetic variation; Genetic diversity; Holocentric chromosomes; cis-regulatory variation; Allele-specific expression; populationsgenetik; Population Genetics;

    Abstract : Understanding the role of genetic divergence and recombination in adaptation is crucial to understanding the evolutionary potential of species since they can directly affect the levels of genetic variation present within populations or species. Genetic variation in the functional parts of the genome such as exons or regulatory regions is the raw material for evolution, because natural selection can only operate on phenotypic variation already present in the population. READ MORE

  2. 2. Genetic variation and sexual reproduction in a moss with dwarf males, Homalothecium lutescens

    Author : Frida Rosengren; Biodiversitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; bryophytes; mosses; dwarf males; sexual reproduction; genetic variation; genetic structure; inbreeding; isozymes; allozymes; SNP; sporophytes; spore; fertilization; fertility;

    Abstract : Dwarf males occur in many unrelated groups of organisms. Among land plants they are unique to mosses. Moss dwarf males originate from male spores that land and germinate on the female where their final size is restricted to a few mm. Fertilization in mosses occur over short distances with swimming spermatozoids. READ MORE

  3. 3. Genetic adaptation to soil acidification in four grasses

    Author : Pernilla Göransson; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Växtekologi; Plant ecology; Deschampsia flexuosa; Deschampsia cespitosa; Elymus caninus; Poa nemoralis; arbuscular mycorrhiza; stress; tolerance; genetic variation; local adaptation; Al; Soil acidification; pH;

    Abstract : Soil acidification has become a source of serious concern in many parts of the world. In southern Sweden, the deposition of acidifying substances, such as nitrogen and sulphur compounds, has decreased the mean pH of forest soils by almost one unit since the 1950s. READ MORE

  4. 4. Geographic variation in life cycles : Local adaptation and ecological genetics in a temperate butterfly

    Author : Olle Lindestad; Karl Gotthard; Sören Nylin; Christopher W Wheat; Greg Ragland; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; voltinism; local adaptation; insect; life cycle; seasonality; genomics; life history; zoologisk ekologi; Animal Ecology;

    Abstract : Conditions in nature change with the seasons, necessitating seasonal adaptations that synchronize the life cycles of organisms with their surroundings. Such regulatory adaptations must vary between populations to track local variation in climate and seasonality; this local adaptation is facilitated by locally specific seasonal cues, but may be hampered by gene flow and genetic history. READ MORE

  5. 5. Population size, viability and genetic diversity in the orchid Gymnadenia conopsea

    Author : Linus Söderquist; Nina Sletvold; Sophie Karrenberg; Hans Jacquemyn; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; demography; extinction probability; genetic diversity; genetic rescue; genetic structure; Gymnadenia conopsea; orchid conservation; population viability; population size; Biology with specialization in Ecological Botany; Biologi med inriktning mot ekologisk botanik;

    Abstract : In this thesis, I combined controlled crosses with genetic and demographic data to examine how a main conservation value indicator, population size, was associated with estimates of population viability. I focused on the still common, but decreasing, perennial orchid Gymnadenia conopsea at two spatial scales—locally on the island Öland, in SE Sweden, and regionally across Scandinavia. READ MORE