Sökning: "Diapause"
Visar resultat 1 - 5 av 17 avhandlingar innehållade ordet Diapause.
1. Unraveling the regulatory mechanisms of pupal diapause termination
Sammanfattning : Diapause is an essential part of many insect’s life cycle and is a developmental halt induced by environmental cues in advance of deteriorating conditions. Insects typically enter diapause to avoid unfavorable environmental conditions like low temperatures, poor food quality and the absence of conspecifics. LÄS MER
2. The diapause switch : Evolution of alternative developmental pathways in a butterfly
Sammanfattning : Diapause decision is a classic example of a threshold switch mechanism with cascading effects on morphology, behaviour and life-history traits. This thesis addresses the downstream effects of the insect diapause switch, with the main focus on pathway-specific regulation of life-history traits, using the speckled wood butterfly (Pararge aegeria) as a study species. LÄS MER
3. Functional genomics of diapause in two temperate butterflies
Sammanfattning : Natural selection will act on a given phenotype to maximize fitness in a particular environment, even if this would result in reduced fitness in other environments. In insects some of the strongest selection pressures act on timing life cycles to seasonal variation in environmental conditions, in order to maximize growth, reproduction, and to anticipate the onset of winter. LÄS MER
4. Life history evolution during a climate-driven butterfly range expansion
Sammanfattning : Climate change pushes species polewards and upwards – as temperatures rise, species move to areas that were previously too cold for them. During range expansions, species encounter unfamiliar environmental conditions, which may require evolutionary adaptation, but expanding populations may often be hampered by their genetic and demographic properties. LÄS MER
5. Ecology of zooplankton communities: climate, dormancy, and benthic-pelagic coupling
Sammanfattning : This thesis describes how influences, such as top down and bottom up forces, shape zooplankton communities in shallow lakes. I have also extended the traditional food-web theory by investigating the effects of climate on total biomass, taxonomic composition, and temporal properties of zooplankton communities. LÄS MER