Sökning: "Zoology"

Visar resultat 1 - 5 av 390 avhandlingar innehållade ordet Zoology.

  1. 1. The evolution of courtship rituals

    Författare :Carl Adam Wachtmeister; Innes Cuthill; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; zoologi; Zoology;

    Sammanfattning : The fact that many animals engage in highly ornamented and conspicuous display behaviours in connection with reproduction has received much attention in zoology ever since Darwin launched his theory of sexual selection. This thesis intends to investigate the evolution of such display behaviour. LÄS MER

  2. 2. Flower Cues for Hawkmoths: Colour, Place and Odour

    Författare :Anna Balkenius; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Zoologi; Zoology; olfaction; vision; learning; multimodal; Macroglossum stellatarum; Hawkmoth; Deilephila elpenor;

    Sammanfattning : Flowers use different cues to attract pollinators including colour and odour. How do hawkmoths use these cues to find the flowers? This question was investigated in two species of hawkmoth, the diurnal species, Macroglossum stellatarum, and the nocturnal species, Deilephila elpenor. Both species have colour vision and D. LÄS MER

  3. 3. Maternal investment in male and female offspring in the fallow deer

    Författare :Björn Birgersson; Kjell Wallin; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Animal physiology; Zoofysiologi; zoologi; Zoology;

    Sammanfattning : In this thesis, I investigate whether mothers of the polygynous fallow deer, Dama dama, bias their investment towards male offspring. I aim to answer the specific questions: (i) how is offspring fitness related to maternal investment?; (ii) do male fawns grow faster than female fawns during the period of maternal investment, and if so, why?; (iii) are male fawns more costly to raise than female fawns?; (iv) do fallow deer mothers adjust the sex of their offspring in relation to their ability to invest resources? To answer these questions I have collected and analysed data on reproduction of an enclosed fallow deer population and also performed an experimental study in which the level of investment was controlled for. LÄS MER

  4. 4. Mechanisms in the photoperiodic control of reproduction in the three-spined stickleback, Gasterosteus aculeatus

    Författare :Cecilia Bornestaf; Hilmar Meissl; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; zoologi; Zoology;

    Sammanfattning : .... LÄS MER

  5. 5. Risk assessment and contest behaviour in the Cichlid fish Nannacara anomala

    Författare :Olle Brick; Felicity A. Huntingford; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; zoologi; Zoology;

    Sammanfattning : The risk of predation is an important factor for our understanding of animal behaviour in general. This thesis investigates the influence of predation risk on fighting behaviour in the cichlid fish Nannacara anomala. LÄS MER