Sökning: "darwin"

Visar resultat 16 - 20 av 20 avhandlingar innehållade ordet darwin.

1. 16. Sexual conflict and selection on pistil and pollen traits

   Författare :Josefin Madjidian; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Antagonistic trait; Collinsia heterophylla; delayed stigma receptivity; direct cost; first-donor advantage; gender bias; heritability; indirect benefit; mate choice; mixed-mating system; paternal diversity; pollen competition; pollen deposition; pollen load size; pollen tube growth rate; self-compatibility; semantics; sexual conflict; sexual selection; sexually antagonistic co-evolution;

   Sammanfattning : The incidence of sexual selection in plants is today acknowledged, however, just as in animals, evolution and maintenance of mate choice is gravely underexplored. Moreover, the potential for sexual conflicts to occur in plants has only been assessed empirically to a very limited degree. LÄS MER

3. 17. Island biogeography and population divergence in the Skyros wall lizard

   Författare :Anna Runemark; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Podarcis gaigeae; inbreeding; predation release; polymorphism; island gigantism; the island rule; genetic drift; sexual selection; natural selection; island biology; Evolution;

   Sammanfattning : Islands are cradles for new biodiversity and provide natural laboratories for the study of population divergence. In my thesis, I investigated the role of different evolutionary processes in the population divergence in the Skyros wall lizard (Podarcis gaigeae), a species where islet populations have strongly diverged morphologies. LÄS MER

4. 18. Genetic adaptation to soil acidification in four grasses

   Författare :Pernilla Göransson; Biologiska institutionen; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

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

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

   Sammanfattning : 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. LÄS MER

7. 20. Individual consistency in bird migration

   Författare :YANNIS VARDANIS; Evolutionär ekologi; []
   Nyckelord :bird migration; telemetry; bird ringing; individual consistency; repeatability; site fidelity; routes; timing; annual cycle; meta-analysis;

   Sammanfattning : Slight differences, which appear in the individual animals of the same species and population have been recognised and appreciated ever since Darwin. These consistent intra-specific differences in animals have been considered very important because they are often inherited, and thus, provide the basic material for evolution to act on. LÄS MER