Sökning: "biological cost"

Visar resultat 26 - 30 av 338 avhandlingar innehållade orden biological cost.

  1. 26. The evolutionary ecology of niche separation : Studies on the sympatric butterflies Leptidea sinapis and Leptidea reali

    Författare :Magne Friberg; Wiklund Christer; John N. Thompson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lepidoptera; ecological character displacement; reproductive isolation; species discrimination; habitat; host plant; life history; sexual selection; female choice; Biology; Biologi; zoologisk ekologi; Animal Ecology;

    Sammanfattning : Studies of ecology and evolution have become largely integrated, and increasing attention is paid to the role of ecology for speciation and post speciation divergence. In this thesis I have applied an in-depth approach studying the ecology of a butterfly species pair; the morphologically virtually identical sister-species, the Wood white (Leptidea sinapis) and Reál’s wood white (Leptidea reali). LÄS MER

  3. 27. Enabling massive genomic and transcriptomic analysis

    Författare :Henrik Stranneheim; Joakim Lundeberg; Elaine Mardis; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; DNA; RNA; sequencing; massively parallel sequencing; alignment; assembly; single nucleotide polymorphism; LHON;

    Sammanfattning : In recent years there have been tremendous advances in our ability to rapidly and cost-effectively sequence DNA. This has revolutionized the fields of genetics and biology, leading to a deeper understanding of the molecular events in life processes. LÄS MER

  4. 28. Multiplex markers in a plant breeding perspective

    Författare :Mats Hansen; Biokemi och Strukturbiologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Plant biochemistry; plant breeding; SNP; RAPD; molecular markers; AFLP; Växtbiokemi;

    Sammanfattning : Plant breeding is largely depending on the repeated selection for desirable traits. This process is both time and labour consuming, making the development of commercial plant varieties a slow and costly activity. LÄS MER

  5. 29. Behaviour and life-history responses to chick provisioning under risk of nest predation

    Författare :Sönke Eggers; David Winkler; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Biology; Chick provisioning; clutch size; delayed dispersal; nest concealment; nest predation; parental care; population decline; Perisoreus infaustus; Siberian jay; Biologi; Biology; Biologi; populationsbiologi; Population Biology;

    Sammanfattning : This thesis examines risk management in breeding Siberian jays (Perisoreus infaustus), which is indigenous to the northern taiga. Parent behaviour and the nest are cryptic. A new nest is built each year. It is placed on spruce or pine branches close to the trunk and well insulated with lichens, feathers and reindeer hair. LÄS MER

  7. 30. Colour Vision in Birds : Comparing behavioural thresholds and model predictions

    Författare :Peter Olsson; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gallus gallus; receptor noise; visual modelling; animal training; colour discrimination; colour constancy;

    Sammanfattning : Birds use colour vision for many biologically relevant behaviours such as foraging and mate choice. Bird colour vision is mediated by four types of single cones, giving them an extra dimension of colour information compared to trichromatic humans. LÄS MER