Sökning: "TARSUS LENGTH"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden TARSUS LENGTH.

  1. 1. LIVING WITH PARASITES: AVIAN MALARIA, TELOMERE LENGTH AND LIFE HISTORY TRADE-OFFS

    Författare :Asghar Muhammad; MEMEG; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Avian malaria; Plasmodium; qPCR; parasitemia; life history; reproduction; survival; feather growth; MHC; telomere length; heritability; telomere loss; fitness; wild population; Acrocephalus arundinaceus; Delichon urbica;

    Sammanfattning : Haemosporidia is a well-studied group of parasites, which infect mammals, reptiles and birds and use blood sucking vectors for their transmission. By conducting natural population studies and experimental infections, We have been able to detect and quantify Haemosporidia from avian blood to investigate how these pathogens affect their avian hosts. LÄS MER

  3. 2. Genetic and environmental factors influencing growth and survival in willow tits, Parus montanus

    Författare :Anna Thessing; Tomas Pärt; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; zoologi; Zoology;

    Sammanfattning : This thesis concerns with the relationship between genetic and environmental attributes and their influence on offspring growth and survival in willow tits (Parus montanus). It also investigates the occurrence of directional or stabilising selection on body size during different life stages or times of the year. LÄS MER

  4. 3. Causes and consequences of quantitative trait variation for reproductive performance in hole nesting birds

    Författare :Robert Przybylo; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; timing of breeding; climate change; parental and territorial quality; morphology; sexual size dimorphism; intersexual niche differentiation; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

    Sammanfattning : This thesis examines the causes and consequences of environmental variability and individual morphological differences on breeding success and survival in three hole nesting birds.An analysis of directional and stabilising natural selection in Collared Flycatchers (Ficedula albicollis) suggested that forces of selection acting on quantitative traits are weak and cannot explain the observed sexual size dimorphism (SSD) in this species. LÄS MER

  5. 4. Development and maintenance of quality indicators in pheasants

    Författare :Thomas Ohlsson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PHA; ELISA; immunocompetence; carotenoid coloration; male ornaments; fluctuating asymmetry; growth; early development; Phasianus colchicus; egg size; sexual selection; Animal ecology; Djurekologi; Ecology; Ekologi;

    Sammanfattning : Females often base their choice of mates on the expression, size or intensity, of male sexual ornaments. Indicator models of sexual selection assume that females assess male genetic quality through the expression of these secondary sexual characters. LÄS MER

  7. 5. Parental and embryonic behaviours in precocial birds

    Författare :Irene Persson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; pheasants; growth rate; oxygen consumption; hatch synchronization; incubation behaviour; nest predation; physical condition; Egg laying; primary sex ratio; mallards; Animal ecology; Djurekologi;

    Sammanfattning : This thesis deals with behaviours during reproduction in precocial birds, both from the perspective of the female and of the embryos. Female pheasants in good physical condition laid larger eggs and produced a higher proportion of daughters than females in poor condition. LÄS MER