Sökning: "natural selection"

Visar resultat 6 - 10 av 1234 avhandlingar innehållade orden natural selection.

  1. 6. Universal Instruction Selection

    Författare :Gabriel Hjort Blindell; Christian Schulte; Peter van Beek; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; instruction selection; code generation; compilers; constraint programming; combinatorial optimization; Informations- och kommunikationsteknik; Information and Communication Technology;

    Sammanfattning : In code generation, instruction selection chooses instructions to implement a given program under compilation, global code motion moves computations from one part of the program to another, and block ordering places program blocks in a consecutive sequence. Local instruction selection chooses instructions one program block at a time while global instruction selection does so for the entire function. LÄS MER

  3. 7. Sexual selection and intersexual conflicts in water striders

    Författare :Göran Arnqvist; Andrew Sih; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Sexual selection; mating behaviour; parasitism; sperm competition; mate guarding; sexual dimorphism; natural selection; sexual conflicts; water striders; Heteroptera; Gerridae; Gerris; Scelionidae; Trypanosomatidae; Skinnbaggar; Etologi;

    Sammanfattning : .... LÄS MER

  4. 8. Population genomic analyses of regulatory variation and selection in Brassicaceae species

    Författare :Robert Horvath; Tanja Slotte; Peter Hambäck; Douglas G. Scofield; Matthew Webster; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Capsella grandiflora; Arabidopsis thaliana; Arabidopsis lyrata; natural selection; gene expression variation; DNA and gene body methylation; transposable elements; DNA accessibility; gene expression noise; epigenetic silencing; linked selection; ekologi och evolution; Ecology and Evolution;

    Sammanfattning : The impact of selection on regulatory variation and the contribution of regulatory changes to phenotypic variation has long been debated in evolutionary genetics. Because cis-regulatory elements such as promoters and enhancers can be difficult to identify, it has been more challenging to quantify the impact of selection on variation in cis-regulatory regions than in protein-coding regions. LÄS MER

  5. 9. Opportunity for natural selection in Sweden : a study of childhood mortality and differential reproductivity

    Författare :Helen M. E. Hed; Marianne Rasmuson; Aldur Eriksson; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Opportunity for selection; Crow s index; Demography; Sweden; 1600-1980; Mortality; Fertility; genetik; Genetics;

    Sammanfattning : Opportunity for natural selection in human populations has so far mainly been studied on anthropological data for tribal populations or on census data for nations. The present study is mainly based on data on individual lifehistories but also, for part of the longitudinal study, on census data. LÄS MER

  7. 10. Evolution of Spur Length in a Moth-pollinated Orchid

    Författare :Elin Boberg; Jon Ågren; W. Scott Armbruster; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Platanthera bifolia; floral evolution; natural selection; pollination; spur length; population differentiation; divergent selection; disruptive selection; reproductive isolation; Biology; Biologi; Ecological Botany; Ekologisk botanik;

    Sammanfattning : There is considerable evidence that pollinator shifts can explain many differences in flower morphology between closely related plant species, but the extent to which pollinator shifts can explain the maintenance of among-population variation in floral traits within species is poorly known. In this thesis, I combined comparative and experimental approaches to examine the evolution of floral traits in the moth-pollinated orchid Platanthera bifolia. LÄS MER