Sökning: "reproductive effort"

Visar resultat 16 - 20 av 36 avhandlingar innehållade orden reproductive effort.

1. 16. Choice, competition, and interactions between episodes of sexual selection

   Författare :Charel Reuland; John Fitzpatrick; Ingo Schlupp; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; contest competition; sperm competition; mate choice; cryptic choice; sperm quality; reproductive status; social dominance; etologi; Ethology;

   Sammanfattning : Choice and competition are essential parts of evolutionary biology. In an effort to pass their genes from one generation to the next, animals may carefully choose their mating partners, and/or compete for access to mates. LÄS MER

3. 17. Facing the negative impact of cancer treatment on fertility : fertility-related communication and reproductive concerns following a cancer diagnosis

   Författare :Gabriela Armuand; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :;

   Sammanfattning : Background: Having children is an important part of life for many men and women. However, cancer treatment may have a negative impact on fertility by, for example, affecting eggs or sperm production. LÄS MER

4. 18. Causes and consequences of life-history variation : The effects of parasites, glucocorticoids, and environmental conditions in the collared flycatcher (Ficedula albicollis)

   Författare :Kevin Fletcher; Lars Gustafsson; Anders Pape Moller; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Collard flycatcher; Haemosporidian blood parasite; glucocorticoid; life history;

   Sammanfattning : Life-history is the study of all the different stages of life that affect reproductive success and survival between the birth and death of an organism. The reproductive output of an organism is constrained by many things including time, resource, disease agents and environmental conditions. LÄS MER

5. 19. Trade-offs between life history traits and immune defence in the collared flycatcher Ficedula albicollis

   Författare :Dag Nordling; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

   Sammanfattning : This thesis examines the effects of reproductive effort on immune function and parasite resistance in breeding collared flycatchers, Ficedula albicollis. It also focuses on the role of the immune function in the trade-off between number and fitness of offspring. LÄS MER

7. 20. Causes and consequences of blood parasite infections in birds

   Författare :Martin Stjernman; Biodiversitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Animal physiology; Djurfysiologi; Parasitologi människa och djur ; Parasitology human and animal ; maternal transfer; stabilising selection; parasite resistance; parasites; trade-off; cost of reproduction; Ficedula hypoleuca; pied flycatcher; Haemoproteus; blue tit; Parus caeruleus;

   Sammanfattning : Parasites are ubiquitous and can cause significant fitness reductions to their hosts. Therefore, selection for the evolution of host resistance should be strong. However, resistance may be costly and should be traded-off against other fitness related traits. LÄS MER