Search for dissertations about: "moth pollinators"
Found 5 swedish dissertations containing the words moth pollinators.
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1. Selection and Floral Evolution in Platanthera bifolia and P. chlorantha (Orchidaceae)
Abstract : Natural selection mediated by pollinators has influenced the evolution of floral diversity of the flowering plants (angiosperms). The scope of this thesis was to study: 1) phenotypic selection, 2) mating systems, and 3) floral shifts involved in plant speciation. Model plant species were Platanthera bifolia and P. chlorantha (Orchidaceae). READ MORE
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2. Evolution of Spur Length in a Moth-pollinated Orchid
Abstract : There is considerable evidence that pollinator shifts can explain many differences in flower morphology between closely related plant species, but the extent to which pollinator shifts can explain the maintenance of among-population variation in floral traits within species is poorly known. In this thesis, I combined comparative and experimental approaches to examine the evolution of floral traits in the moth-pollinated orchid Platanthera bifolia. READ MORE
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3. Selection on floral traits in Primula farinosa
Abstract : Flowers and inflorescences have evolved in relation to animals for at least 100 million years. Plants attract pollinators with large, conspicuous, bright-coloured or scented flowers. These display attributes, however, also attract herbivores. READ MORE
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4. Flower Cues for Hawkmoths: Colour, Place and Odour
Abstract : Flowers use different cues to attract pollinators including colour and odour. How do hawkmoths use these cues to find the flowers? This question was investigated in two species of hawkmoth, the diurnal species, Macroglossum stellatarum, and the nocturnal species, Deilephila elpenor. Both species have colour vision and D. READ MORE
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5. Pollinator-mediated selection and the evolution of floral traits in orchids
Abstract : In this thesis, I combined manipulations of traits and pollination environment with analysis of phenotypic selection to examine causes of variation in strength and mode of selection on floral traits, and I conducted a reciprocal sowing experiment to test for local adaptation in germination success. I tested the following predictions (1) the opportunity for selection, and the strength of pollinator-mediated and net selection increase with increasing pollen limitation, (2) the effects of traits affecting pollinator attraction and traits affecting pollination efficiency are non-additive and this leads to pollinator-mediated correlational selection, (3) the effects of spur length on pollen removal, pollen receipt, and female fitness differ between populations with short-tongued and populations with long-tongued pollinators, and (4) local adaptation at the stage of germination contributes to the maintenance of ecotypes growing in grasslands and woodlands, respectively. READ MORE