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Visar resultat 1 - 5 av 12 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Sexual conflict and selection on pistil and pollen traits

   Författare :Josefin Madjidian; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Antagonistic trait; Collinsia heterophylla; delayed stigma receptivity; direct cost; first-donor advantage; gender bias; heritability; indirect benefit; mate choice; mixed-mating system; paternal diversity; pollen competition; pollen deposition; pollen load size; pollen tube growth rate; self-compatibility; semantics; sexual conflict; sexual selection; sexually antagonistic co-evolution;

   Sammanfattning : The incidence of sexual selection in plants is today acknowledged, however, just as in animals, evolution and maintenance of mate choice is gravely underexplored. Moreover, the potential for sexual conflicts to occur in plants has only been assessed empirically to a very limited degree. LÄS MER

3. 2. Mating strategies and sexual conflicts in aquatic invertebrates: consequences for evolutionary differentiation

   Författare :Kristina Karlsson; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Asellus aquaticus; Dytiscidae; gender bias; genetic polymorphism; mate guarding; parallel evolution; plasticity; population divergence; sexual conflict; sexually antagonistic selection; sexual selection;

   Sammanfattning : In this thesis I investigated how mating related strategies may differ among populations and how these strategies evolve in response to their local ecological environments. I have used two different study systems of aquatic invertebrates: diving beetles (Dytiscidae) and the fresh water isopod Asellus aquaticus. LÄS MER

4. 3. Polyandry and the evolution of reproductive divergence in insects

   Författare :Tina Nilsson; Göran Arnqvist; David Hosken; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; Bruchidae; cryptic female choice; multiple mating; sexual conflict; sexually antagonistic coevolution; sexual selection; speciation; sperm competition; Tenebrionidae; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

   Sammanfattning : Multiple mating by females is common in nature. Yet, the evolution and maintenance of polyandry remains a bit of an evolutionary puzzle. It was my aim in this thesis to reach a greater understanding of this phenomenon as well as to investigate the consequences of polyandry on the evolution of reproductive divergence in insects. LÄS MER

5. 4. Sexual conflict and male-female coevolution in the fruit fly

   Författare :Urban Friberg; Göran Arnqvist; Daniel Promislow; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cryptic male mate choice; Drosophila melanogaster; female mate choice; multiple mating; sexual conflict; sexually antagonistic coevolution; sexual selection; speciation; sperm competition; Biology; Biologi;

   Sammanfattning : Harmony and cooperation was for long believed to dominate sexual interactions. This view slowly started to change 25 years ago and is today replaced with a view where males and females act based on what is best from a costs-benefits perspective. LÄS MER

7. 5. MHC polymorphism in a songbird : Fitness, mate choice, and sexual conflict

   Författare :Jacob Roved; MEMEG; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Major histocompatibility complex; MHC diversity; MHC haplotypes; sexually antagonistic selection; costs of immune responses; adaptive immunity; great reed warbler; songbird;

   Sammanfattning : Sex differences in immune responses have been observed across a wide range of animal species, with the generaltendency that males have weaker immune responses than females. These differences are at least partly caused by immune-regulating effects of sex hormones, and have been associated with an increased prevalence of autoimmune disorders in females and with a general tendency for males to be parasitized more often than females. LÄS MER