Sökning: "Evolutionär ekologi"

Visar resultat 11 - 15 av 54 avhandlingar innehållade orden Evolutionär ekologi.

1. 11. Hybrid zone dynamics, assortative mating, and migratory programmes in a willow warbler migratory divide

   Författare :Keith W. Larson; Susanne Åkesson; Staffan Bensch; Martin Schaefer; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; migratory divide; phenotype; willow warbler; hybrid zone; tension zone; Phylloscopus trochilus; migratype; assortative mating; migration; biology; biologi; evolutionär genetik; evolutionary genetics; migratory divide; phenotype; willow warbler; hybrid zone; tension zone; Phylloscopus trochilus; migratype; assortative mating; migration;

   Sammanfattning : In this thesis I will compare and contrast the two willow warbler subspecies (Phylloscopus trochilus trochilus and P. t. acredula) with differing migratory phenotypes (or "migratype") in the context of their migratory divide and hybrid zone in central Sweden. Their migratory programs differ in the direction and distance traveled during migration. LÄS MER

3. 12. Physical and biological dispersal barriers in invasive, bloom-forming microalgae

   Författare :Ingrid Sassenhagen; Enhet akvatisk ekologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dispersal barriers; microalgae; phenotypic differentiation; population genetics; priority effects;

   Sammanfattning : For a long time microorganisms were assumed to have unlimited dispersal due to their small size and high cell numbers. Most microbial species can be transported by water currents, in water droplets by wind and attached to other organisms. LÄS MER

4. 13. Adaptation and Constraint in the Plant Reproductive Phase

   Författare :Kjell Bolmgren; Ove Eriksson; Bengt Oxelman; Jeff Ollerton; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; phenology; fleshy fruits; phylogenetic comparative methods; phylogenetic constraints; Rhamnus; Frangula; Frangula alnus; key innovations; allometry; diversity; phylogeny; seed size; frugivory; germination; recruitment; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : Conservatism is a central theme of organismic evolution. Related species share characteristics due to their common ancestry. Some concern have been raised among evolutionary biologists, whether such conservatism is an expression of natural selection or of a constrained ability to adapt. LÄS MER

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

   Författare :Adriana Puentes; Jon Ågren; Jenny Hagenblad; Roosa Leimu Brown; Uppsala universitet; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

7. 15. Disruption of moth mating behaviour by olfactory and auditory cues

   Författare :Glenn Svensson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Djurekologi; ultrasound; predation risk; selection; heritability; flight tunnel; harmonic radar; pest control; mating disruption; pheromone communication; Pyralidae; Lepidoptera; Noctuidae; Animal ecology;

   Sammanfattning : The impact of olfactory and auditory cues on the mating behaviour in two species of moths, Agrotis segetum (Noctuidae) and Plodia interpunctella (Pyralidae), was investigated to evaluate their potential use in integrated pest management. The flight behaviour of male A. LÄS MER