Search for dissertations about: "Reproductive ecology"

Showing result 1 - 5 of 176 swedish dissertations containing the words Reproductive ecology.

2. 1. Evolutionary ecology of arctic char (Salvelinus alpinus (L.)) : Intra- and interspecific interactions in circumpolar populations

   Author : Johan Hammar; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Arctic char; Salvelinus alpinus; biogeography; niche; life history; population ecology; intra- and interspecific interactions; cannibalism; competition; landlocked; marginal populations; species border; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Abstract : This thesis examines a suite of ecological and genetic mechanisms influencing the fundamental and realized niche borders of European and North American populations of the Arctic char (Salvelinus alpinus (L.)) species complex in allopatry as well as in sympatry with brown trout (Salmo trutta) or brook trout (Salvelinus fontinalis). READ MORE

4. 2. Female Reproductive Strategies in the Ruff (Philomachus pugnax)

   Author : Katherine Thuman; Fredrik Widemo; Robert Montgommery; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Abstract : Traditionally, females have been considered to be strictly monogamous. Today, we know that females in the majority of species actively seek out and mate with several males. Trying to understand female preferences, including what benefits mate choice entails, has been the focus of intense research during the last decades. READ MORE

5. 3. Pollinators, Enemies, Drought, and the Evolution of Reproductive Traits in Primula farinosa

   Author : Per Toräng; Jon Ågren; Johan Ehrlén; Rebecca Irwin; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ecology; Alternative reproductive strategies; climate change; facilitation; floral display; flowering phenology; frequency-dependent selection; genetic diversity; life-history strategies; local adaptation; pollination; predation; Primula farinosa; reproductive effort; soil disturbance; stochastic growth rate; Ekologi;

   Abstract : In this thesis, I combined comparative and experimental approaches to examine selection on reproductive traits and population differentiation in the insect-pollinated, self-incompatible, perennial herb Primula farinosa. More specifically, I (1) determined whether the effects of floral display and interactions with pollinators and seed predators, and plant reproductive success were frequency-dependent and affected by surrounding vegetation context, (2) examined the consequences of intermittent drought years on population dynamics using numerical simulations based on demographic data collected over seven years, (3) analyzed among-population differentiation in flowering phenology and reproductive allocation, and its relationship to soil-depth at the site of origin. READ MORE

6. 4. Reproductive allocation and costs of reproduction in subarctic herbs : A resource-based perspective

   Author : Åsa M. Hemborg; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; Altitudinal gradient; Plant size; Predispersal seed predation; Reproductive effort; Resourcedynamics; Seasonal variation; Sexual dimorphism; Somatic costs; Unisexual plants; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; ekologisk botanik; Ecological Botany;

   Abstract : The influence of internal and external factors on two major plant life history components, i.e., reproductive allocation and costs of reproduction, was examined for nine perennial herbs in subarctic Swedish Lapland. In one study, comparisons were made between Sweden and the French Alps. READ MORE

7. 5. Causes and consequences of quantitative trait variation for reproductive performance in hole nesting birds

   Author : Robert Przybylo; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Ecology; timing of breeding; climate change; parental and territorial quality; morphology; sexual size dimorphism; intersexual niche differentiation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Abstract : This thesis examines the causes and consequences of environmental variability and individual morphological differences on breeding success and survival in three hole nesting birds.An analysis of directional and stabilising natural selection in Collared Flycatchers (Ficedula albicollis) suggested that forces of selection acting on quantitative traits are weak and cannot explain the observed sexual size dimorphism (SSD) in this species. READ MORE