Sökning: "Costs of reproduction"

Visar resultat 1 - 5 av 47 avhandlingar innehållade orden Costs of reproduction.

1. 1. Allocation of body resources to reproduction in butterflies

   Författare :Fredrik Stjernholm; Bengt Karlsson; Christer Wiklund; Jane K. Hill; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Zoology; Ecology; Butterflies; Reproduction; Life histories; Trade-offs; Resource use; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : The life-history of an organism can be studied and understood in terms of acquisition and expenditure of resources. In butterflies, the use of resources for reproduction has been the focus of much research due to the possibility to easily quantify both the input of resources from different sources over the life-cycle as well as the partitioning of these resources to reproduction. LÄS MER

3. 2. Physiological trade-offs in reproduction and condition dependence of a secondary sexual trait

   Författare :Måns S. Andersson; Victor Apanius; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Trade-offs; life history; immune ecology; cost of reproduction; costs of immune response; sexual selection; migration; moult; Newcastle disease; HbA1C; Ficedula albicollis; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; Animal Ecology; zooekologi;

   Sammanfattning : This thesis examines parental condition, how it is traded off against reproduction and how it is displayed in a secondary sexual trait. The studies were performed on nest-box breeding collared flycatchers Ficedula albicollis on the island of Gotland, in the Baltic Sea. LÄS MER

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

   Författare :Åsa M. Hemborg; Uppsala universitet; []
   Nyckelord :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;

   Sammanfattning : 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. LÄS MER

5. 4. Reproduction and moult in pied and collared flycatchers (Ficedula hypoleuca and F. albicollis) : A life-history approach

   Författare :Christer Hemborg; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Breeding time; Costs of reproduction; Long-distance migrant; Moult-breeding overlap; Sexual conflict; Survival probability; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Sammanfattning : This thesis examines the trade-offs between investments in reproduction and self-maintenance (moult) in pied and collared flycatchers (Ficedula hypoleuca and F. albicollis). These two long-distance migratory passerine bird species were studied on the breeding grounds in Fennoscandia and in England. LÄS MER

7. 5. Costs and Tactics in the Evolution of Reproductive Effort

   Författare :Ingemar Jönsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; capital breeding; Falco tinnunculus; body mass; DEE; reproductive effort; reproductive costs; income breeding; Animal ecology; Djurekologi;

   Sammanfattning : This study focuses on various aspects of costs of reproduction and the evolution of energetic breeding tactics. It emphasizes the distinction between demographic costs of reproduction expressed already before current offspring have reached independence (prebreeding costs), and costs expressed only after offspring independence (postbreeding costs). LÄS MER