Search for dissertations about: "feathers"

Showing result 1 - 5 of 22 swedish dissertations containing the word feathers.

  2. 1. Feathers by day, membranes by night - Aerodynamic performance in bird and bat flight

    Author : Florian Muijres; Evolutionär ekologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; animal flight; aerodynamics; vortex wake; actuator disk; flight performance; span efficiency; bird; bat; wind tunnel; PIV; Pied Flycatcher; Glossophaga soricina; Leptonycteris yerbabuenae;

    Abstract : The efficiency and performance of a flying animal is directly related to the aerodynamics around its body and flapping wings. Here, I have developed methods for quantifying the wake dynamics around a flying animal. The results are used to estimate the aerodynamic performance of flapping flight. READ MORE

  4. 2. Platinum Group Elements in Birds of Prey

    Author : Kristine H. Ek; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rhodium; bird of prey; platinum; laser ablation; palladium; ICP-MS; airborne particles;

    Abstract : The environmental concentrations of Pd, Pt and Rh (three of the platinum group elements, PGE) have increased since the introduction of exhaust catalysts on automobiles. A limited understanding of the environmental distribution and effects of the platinum group elements has raised concern over their potential biological availability. READ MORE

  5. 3. In the wake of a bird - Quantifying aerodynamic performance of avian flight

    Author : Marco Klein Heerenbrink; Evolutionär ekologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; animal flight; flight performance; gliding; powered flight; wing morphology; aerodynamics; biomechanics; birds; jackdaw; Corvus monedula; wind tunnel; PIV;

    Abstract : Flight is an expensive form of locomotion, but also offers the ability to travel great distances at relatively low cost. Birds have developed various adaptations for optimizing flight performance. The main aim of this thesis is to identify how morphological variables in birds affect aerodynamic drag and flight performance. READ MORE

  6. 4. Behaviour and life-history responses to chick provisioning under risk of nest predation

    Author : Sönke Eggers; David Winkler; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Biology; Chick provisioning; clutch size; delayed dispersal; nest concealment; nest predation; parental care; population decline; Perisoreus infaustus; Siberian jay; Biologi; Biology; Biologi; populationsbiologi; Population Biology;

    Abstract : This thesis examines risk management in breeding Siberian jays (Perisoreus infaustus), which is indigenous to the northern taiga. Parent behaviour and the nest are cryptic. A new nest is built each year. It is placed on spruce or pine branches close to the trunk and well insulated with lichens, feathers and reindeer hair. READ MORE

  7. 5. Living in a Variable Environment : Reproductive Decisions in Wild Bird Populations

    Author : Mårten B. Hjernquist; Lars Gustafsson; Marcel Visser; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; evolutionary ecology; competition; sex allocation; paternity; EPP; inadvertent social information; migration; breeding density; territory quality; territory availability; great tit; blue tit; Ficedula albicollis; Biology; Biologi; Animal Ecology; zooekologi;

    Abstract : In nature, environments are often variable and heterogeneous influencing ecological and evolutionary processes. This thesis focus on how animals interact with their environment and how that affects the reproductive decisions they make. READ MORE