Sökning: "multiple mating"

Visar resultat 1 - 5 av 23 avhandlingar innehållade orden multiple mating.

1. 1. 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

3. 2. Reproductive isolation at contact zones

   Författare :Samuel Perini; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; hybrid zone; gene flow; genetic variants; mating; local adaptation; marine species; speciation;

   Sammanfattning : Speciation is among the most important evolutionary processes that contribute to biodiversity. It involves the formation of new species that have become reproductively isolated through a process that is not linear and varies in time and space. LÄS MER

4. 3. 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

5. 4. Adaptive significance of queen mating frequency in ants : In search of benefits of genetic variability

   Författare :Pia J. Gertsch; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; Genetics; genetik;

   Sammanfattning : Fitness effects of polyandry, multiple mating by females, were studied on two ant speciesLasius niger and Formica truncorum. Particular emphasis was put on evaluating diploid male load, which happens when homozygosity in the sex determination locus leads to intendedfemales developing into sterile, diploid males. LÄS MER

7. 5. On the Evolution of Reproductive Systems in Neurospora

   Författare :Rebecka Strandberg; Hanna Johannesson; Paul Dyer; Uppsala universitet; []
   Nyckelord :Neurospora; mating type; pheromone receptor; phylogeny; gene expression; heterothallism; homothallism; pseudohomothallism; alternative splicing; Biology with specialization in Evolutionary Genetics; Biologi med inriktning mot evolutionär genetik;

   Sammanfattning : The aim of this thesis was to study the evolution of reproductive systems and reproductive traits in the fungal genus Neurospora. More specifically, I have investigated the evolutionary forces shaping the genes involved in sexual reproduction, focusing on mating-type (mat) and pheromone receptor (pre) genes. LÄS MER