Sökning: "colour discrimination"

Visar resultat 1 - 5 av 7 avhandlingar innehållade orden colour discrimination.

  1. 1. 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

  3. 2. Colour patterns in warning displays

    Författare :Marianne Aronsson; Gabriella Gamberale-Stille; Olof Leimar; Candy Rowe; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; aposematism; warning colouration; colour patterns; avoidance learning; generalization behaviour; signal design; signal evolution; conspicuousness; mimicry; etologi; Ethology;

    Sammanfattning : In aposematism a prey species use bright colours, often combined with a black contrasting pattern, to signal unprofitability as prey to potential predators. Although there are several different hypotheses about the presence of these internally contrasting patterns, there is little experimental evidence of any beneficial effects. LÄS MER

  4. 3. 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

  5. 4. Plumage Colours and the Eye of the Beholder : The Ecology of Colour and its Perception in Birds

    Författare :Olle Håstad; Mats Björklund; Innes Cuthill; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; ultraviolet; colour vision; opsin; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi;

    Sammanfattning : Virtually all diurnal birds have tetrachomatic vision based on four different colour receptors. As a result, birds are potentially able to perceive their environment in twice as many colours as humans and four times as many colours compared to most other mammals, which are dichromatic. LÄS MER

  7. 5. Colour perception in old age. Colour discrimination, colour naming and colour preferences in 80-year-olds and among individuals suffering from Alzheimer´s disease

    Författare :Helle Wijk; Göteborgs universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES;

    Sammanfattning : .... LÄS MER