Sökning: "male ornaments"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden male ornaments.

  1. 1. The Evolution of Sexually Homologous Ornaments : Selection via Male Mate Choice Coinciding with Male-Male Competition in a Neotropical Mosquito

    Författare :Sandra South; Göran Arnqvist; Russell Bonduriansky; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; sexual selection; Sabethes cyaneus; Diptera; Culicidae; mosquito; mutual ornamentation; sexual selection; mutual mate choice; male mate choice; female ornament; ecology; animal behaviour; Ethology and behavioural ecology; Etologi och beteendeekologi; Animal Ecology; Zooekologi;

    Sammanfattning : The evolution of elaborate male ornaments via sexual selection is well-understood while the selective pressures acting on female ornaments remains unresolved. Female ornaments in species with strong sexual selection on the male homologue of the ornament were originally thought to result from an intersexual genetic correlation. LÄS MER

  3. 2. 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

  4. 3. Female choice and paternal care in the fifteen-spined stickleback, Spinachia spinachia

    Författare :Sara Östlund-Nilsson; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; fifteen-spined stickleback; spinachia spinachia; female choice; paternal care; nest building; ornament; fanning; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; Animal Ecology; zooekologi;

    Sammanfattning : In the fifteen-spined stickleback, Spinachia spinachia, males provide females with direct benefits by fanning, cleaning and guarding the offspring. Males announce their parental skills through intense body shakes during courtship. Females preferred to mate with more intensely shaking males. LÄS MER

  5. 4. Bird-parasite interactions : Using Sindbis virus as a model system

    Författare :Karin M. Lindström; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Developmental biology; Carduelis chloris; Sindbis virus; host-parasite interaction; ornament; social dominance; testosterone; sexual selection; Utvecklingsbiologi; Developmental biology; Utvecklingsbiologi; populationsbiologi; Population Biology;

    Sammanfattning : This thesis focuses on the evolutionary interactions between birds and a parasite, the mosquito-borne Sindbis virus (Togaviridae, Alphavirus). In conclusion, the results show that the Sindbis virus is widespread among birds, and that the fitness of infected hosts may be reduced by the virus. LÄS MER

  7. 5. Bilder av kvinnor och kvinnlighet : genus och kroppsspråk under övergången till kristendomen

    Författare :Eva-Marie Göransson; Elisabeth Arwill-Nordbladh; Stockholms universitet; []
    Nyckelord :HUMANIORA; HUMANITIES; arkeologi; Archaeology;

    Sammanfattning : Gender is a process, a journey. It is in constant change, built up and altered by people who live itSaltering them. In this process, material culture is used both as an agent and as an object of representation.Gotlandic picture stones are the point of departure for this particular gender journey. LÄS MER