Sökning: "Floral evolution"
Visar resultat 11 - 15 av 25 avhandlingar innehållade orden Floral evolution.
11. To Bee or Not to Be : Critical Floral Resources of Wild-Bees
Sammanfattning : In recent decades, the development of strategies to prevent or slow the loss of biodiversity has become an important task for ecologists. In most terrestrial ecosystems wild-bees play a key role as pollinators of herbs, shrubs and trees. The scope of this thesis was to study 1) pollinator effectiveness of specialist bees vs. LÄS MER
12. Plant-Herbivore Interactions and Evolutionary Potential of Natural Arabidopsis lyrata Populations
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
13. Palaeoenvironmental reconstructions from modern and ancient plant DNA
Sammanfattning : Palaeoecological studies on lake sediments and peat archives have provided fundamental knowledge about past environments, nevertheless, a lot remains to be learned. In this thesis, I focussed on plant ancient DNA extracted from sedimentary archives (sedaDNA), in combination with DNA from living trees with the aims of: (1) investigating different extraction methods and levels of inhibition in sediments, (2) investigating postglacial recolonisation history of Norway spruce in Fennoscandia, (3) comparing different sequencing and bioinformatic approaches to investigate past flora changes using sedaDNA and investigating past flora change in contrasting environments (southern Italy versus southern Sweden), and (4) communicating my work more broadly using art. LÄS MER
14. The evolutionary ecology of plant reproductive diversity and floral signals : Mating system and floral scent in Arabis alpina
Sammanfattning : Flowering plants display an extraordinary floral- and reproductive diversity. Variation in the size, shape, colour and scent of flowers, and in systems and strategies of mating, is ubiquitous in comparisons of different species, but also exists among different conspecific populations. LÄS MER
15. Cis-regulatory variation and divergence in Capsella
Sammanfattning : Cis-regulatory changes in e.g. promoters or enhancers that affect the expression of a linked focal gene have long been thought to be important for adaptation. In this thesis, I investigate the selective importance and genomic correlates of cis-regulatory variation and divergence in the genus Capsella, using massively parallel sequencing data. LÄS MER
