Sökning: "maternal selection"

Visar resultat 1 - 5 av 45 avhandlingar innehållade orden maternal selection.

1. 1. Male and female selective mechanisms, reproductive success and gene flow

   Författare :Samuel Kiboi; Biologiska institutionen; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Växtekologi; Plant ecology; Cucumis sativus.; genetic marker; gene flow; reproduction; embryo abortion; resistance; maternal selection; sexual selection; pollen competition; selection;

   Sammanfattning : In this thesis, I have studied male and female selective mechanisms that can affect plant reproductive success and gene flow. I have focussed on sexually selected traits, mainly pollen competition and maternal sorting mechanisms, for example through non-random ovule abortion. LÄS MER

3. 2. Selection, Maternal Effects and Inbreeding in Reindeer Husbandry

   Författare :Lars Rönnegård; Högskolan Dalarna; []
   Nyckelord :breeding programme; communal grazing; randombred populations; Rangifer tarandus tarandus; semidomestic reindeer; gene flow; reindeer; animal breeding; gene flow; random mating; breeding methods; genetic inheritance; population structure; extensive husbandry; sweden;

   Sammanfattning : In extensive grazing systems where several owners’ flocks are allowed to mix, selection strategies will also interact, due to gene flow between flocks. The aim of the thesis was to analyse breeding schemes in terms of genetic gain and rate of inbreeding (?F), given the complexity of ownership and interaction of selection strategies within a mixing reindeer population. LÄS MER

4. 3. Early Experience, Maternal Care and Behavioural Test Design : Effects on the Temperament of Military Working Dogs

   Författare :Pernilla Foyer; Per Jensen; Martin Norsell; Daniel Mills; Försvarshögskolan; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Early experience; Maternal care; Dog; Military Working Dog; Behaviour; Temperament test; Stress; Försvarssystem; Military Technology;

   Sammanfattning : Domestication has resulted in animals with broad variations between as well as within breeds, which allows for the selection and breeding of animals for preferred traits. This selection has affected both the genotypes and phenotypes of animals. LÄS MER

5. 4. 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

7. 5. Evolutionary implications of acidification: a frog’s eye view

   Författare :Katja Räsänen; Andrew Hendry; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; acid stress; amphibians; local adaptation; maternal effects; maternal investment; Biologi; Biology; Biologi; populationsbiologi; Population Biology;

   Sammanfattning : Understanding the diversity of life is one of the main aims of evolutionary biology, and requires knowledge of the occurrence and causes of adaptive genetic differentiation among geographically distinct populations. Environmental stress caused by acidity may cause strong directional selection in natural populations, but is little explored from an evolutionary perspective. LÄS MER