Sökning: "dung beetle"

Hittade 4 avhandlingar innehållade orden dung beetle.

  1. 1. Celestial Orientation in Dim Light

    Författare :Marie Dacke; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polarisation pattern; moon; polrised light detection; twilight; dim light; dung beetle; Zoologi; spider; vision; orientation; Zoology;

    Sammanfattning : The polarization pattern of skylight offers many animals a reference for visual compass orientation. In those cases when this optical compass is identified, the receptors involved are often confined to a small part of an eye built predominantly for other visual tasks. LÄS MER

  2. 2. Movements in the dark : flying, landing and walking in insects

    Författare :THERESE REBER; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; insect; vision; light intensity; bumblebee; retina; behavioural adaptation; flight; landing; dung beetle; nocturnal adaptation; sky compass; straight-line orientation;

    Sammanfattning : Flying, as well as walking insects rely on vision to regulate locomotion, even in the dark when the visual system is much less reliable. To manage visual control of these behaviours at low light intensities, many insects have evolved optical adaptations, such as larger facet lenses and wider rhabdoms, and neural adaptations, such as spatial and temporal summation, to increase their visual sensitivity. LÄS MER

  3. 3. Keep it rolling : Straight-line orientation in South African ball-rolling dung beetles

    Författare :Lana Khaldy; Funktionell zoologi; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ball-rolling dung beetle; Orientation; Heading direction network; Compass; Weighting; Celestial cues; Sun; Polarised light;

    Sammanfattning : Representing a substantial range and variety in morphological and ecological niche, found on all continents of the globe (except for the Antarctic), the ball-rolling dung beetles provide an excellent model in which to study the heading direction network and the factors by which it is influenced. As soon as a ball-rolling dung beetle has located a fresh dung pile to feed on, it immediately starts shaping a piece of dung into a ball, rolling it away from the dung pat in as straight of a trajectory as the terrain allows. LÄS MER

  4. 4. Ommatidial adaptations for vision in nocturnal insects

    Författare :Rikard Frederiksen; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Gain of transduction; Information rate; Signal-to-noise ratio; Apposition eye; Optical sensitivity; Nocturnal insects; Superposition eye; Vision;

    Sammanfattning : Nocturnal vision is a demanding task for insects with small eyes. As it gets dimmer the noise imposed by the stochastic nature of photon arrival makes vision unreliable. Despite this, there are quite a number of animal species that are active at night and apparently see well. LÄS MER