Sökning: "biologiska föräldrar"

Visar resultat 1 - 5 av 16 avhandlingar innehållade orden biologiska föräldrar.

1. 1. Dispersal, inbreeding and fitness in natural populations

   Författare :Bengt Hansson; MEMEG; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; immigration; inbreeding; inbreeding depression; heterozygosity; microsatellite; great reed warbler; bird; Djurekologi; Animal ecology; philopatry; heritability; founder event; dispersal; bottleneck;

   Sammanfattning : To evaluate how inbreeding affects the viability of small populations, it is crucial to determine what constitutes a population (i.e., the number of breeders in local patches and the degree of dispersal), and also to estimate the reproductive consequences of philopatry and emigration. LÄS MER

3. 2. Cooperation and conflict over the struggle to reproduce in harsh environments : An experimental field study on ostriches

   Författare :Julian Melgar; MEMEG; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; social; grupp; konkurrens; konflikt; fusk; värme; stress; tolerans; complexitet; variation; social; group; competition; conflict; cheating; heat; stress; tolerance; complexity; variation;

   Sammanfattning : People are used to hearing that evolution is about the survival of the fittest. Theyimagine a world full of bullies that ruthlessly fight their way to the top in the struggle for life, leaving the weak behind. But this doesn’t need be the case. LÄS MER

4. 3. The effects of temperature on avian physiology, behavior and development

   Författare :Andreas Nord; Evolutionär ekologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; clutch size; Cyanistes caeruleus; ecological immunology; energy expenditure; fever; Ficedula hypoleuca; heterothermy; hypothermia; incubation; life history; metabolic rate; Parus major; RMR; Taeniopygia guttata; temperature; winter;

   Sammanfattning : Temperature is a property of profound matter in all aspects of animal life, affecting both individual energy budgets and the environments in which animals reside. Thus, a proper understanding of the effects of temperature variation is instrumental in understanding not only animal form and function, but also the structure and dynamics of wild populations. LÄS MER

5. 4. Predator-prey interactions in freshwater systems: The importance of chemical communication

   Författare :Kajsa Åbjörnsson; Enhet akvatisk ekologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; marine biology; aquatic ecology; limnology; Marinbiologi; limnologi; akvatisk ekologi; Ecology; Ekologi; Hydrobiology; trophic cascades; non-lethal effects; benefits; costs; heredity; predator experience; alarmsubstances; dietary cues; amphibian larvae; invertebrates; visibility; fish; behaviour; Predator-prey; chemical cues;

   Sammanfattning : Predator released chemical cues provide a valuable source of information to prey organisms that can be used to alter their behaviour in order to reduce predation risk. In this thesis, I have examined under what circumstances chemical cues may be used by prey, and if prey discriminate between different cues. LÄS MER

7. 5. Growth conditions and individual quality in starlings

   Författare :Martin Granbom; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Animal ecology; Djurekologi; cost of reproduction; individual quality; long-term effects; early condition; starling; Sturnus vulgaris;

   Sammanfattning : Variation in growth conditions during ontogeny may result in permanent differences in individual quality. This thesis focuses on how starlings are affected by environmental variation during the nestling period. Both landscape differences in food availability and experimental food supplementation affected survival and growth of nestlings. LÄS MER