Sökning: "animal navigation"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden animal navigation.

  1. 1. Adaptations for nocturnal vision in insect apposition eyes

    Författare :Birgit Greiner; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; temporal and spatial summation; optical and neural adaptations; theoretical modelling.; Djurs anatomi och morfologi; Zoologi; dim light; vision; landmark navigation; nocturnal bees and wasps; Zoology; Animal anatomy; animal morphology;

    Sammanfattning : Due to our own preference for bright light, we tend to forget that many insects are active in very dim light. The reasons for nocturnal activity are most easily seen in tropical areas of the world, where animals face severe competition for food and nocturnal insects are able to forage in a climate of reduced competition and predation. LÄS MER

  2. 2. Magnetic orientation in migratory birds

    Författare :Rachel Muheim; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Animal ecology; Djurekologi; cue-conflict; clock-shift; cue calibration; geomagnetic field; high Arctic latitudes; Emlen funnel; magnetic compass; magnetoreception; navigation; migration; bird; orientation;

    Sammanfattning : My thesis focuses on magnetic orientation in migratory birds, i.e. how they can perceive information from the Earth’s magnetic field and use it for orientation. LÄS MER

  3. 3. Ecology of red admiral migration

    Författare :Oskar Brattström; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Nymphalidae; Lepidoptera; migration patterns; migration; genetic structure; AFLP; lipid content; Inachis io; stable isotopes; orientation; navigation; weather; Animal ecology; red admiral; Vanessa atalanta; Djurekologi;

    Sammanfattning : The red admiral (Vanessa atalanta) is a migratory butterfly that can be found in North America, North Africa, Europe and some parts of Asia. In Europe the main part of the population spend winter in the Mediterranean region and the following spring leave this area to breed further to the north. LÄS MER

  4. 4. Magnetic map sense in animals: effects of geographic and magnetic displacements

    Författare :Jannika Boström; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Oenanthe oenanthe; skylight polarization; geomagnetic map; geomagnetic field; endogenous migration programme; migratory fuelling; orientation; animal navigation;

    Sammanfattning : Migration research is a large and diverse field and in my thesis I have focused on the impact of geomagnetic cues on animal orientation, navigation and migratory fuelling. Several animal species from widely different taxa possess the ability to sense and make use of geomagnetic information during migratory or homing events. LÄS MER

  5. 5. Bird Vision: Spatial acuity and colour discrimination in bright and dim light

    Författare :Olle Lind; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Animal vision; Visual ecology; Colour vision; Spatial acuity; Spatial contrast sensitivity; Dim light; Visual modelling; Behavioural experiments; Birds; Psittaciformes;

    Sammanfattning : Birds use vision to guide navigation, foraging and mate choice, and studies of the limitations in bird visual perception are most helpful for the understanding of bird ecology. Here, I present four studies of bird vision in bright and dim light. LÄS MER