Search for dissertations about: "habitat preferences"

Showing result 1 - 5 of 31 swedish dissertations containing the words habitat preferences.

  2. 1. The evolutionary ecology of niche separation : Studies on the sympatric butterflies Leptidea sinapis and Leptidea reali

    Author : Magne Friberg; Wiklund Christer; John N. Thompson; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Lepidoptera; ecological character displacement; reproductive isolation; species discrimination; habitat; host plant; life history; sexual selection; female choice; Biology; Biologi; zoologisk ekologi; Animal Ecology;

    Abstract : Studies of ecology and evolution have become largely integrated, and increasing attention is paid to the role of ecology for speciation and post speciation divergence. In this thesis I have applied an in-depth approach studying the ecology of a butterfly species pair; the morphologically virtually identical sister-species, the Wood white (Leptidea sinapis) and Reál’s wood white (Leptidea reali). READ MORE

  4. 2. Hybrid zones and speciation – insights from the European crow hybrid zone

    Author : Fredrik Haas; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; microsatellites; mc1r; introgression; hybrid zone; speciation; European crow; Corvus corone; habitat preferences; neural network; sexual imprinting; assortative mating;

    Abstract : In hybrid zones genetically differentiated populations meet and interbreed. As they result from ongoing divergence and potential speciation, such zones provide opportunities to study how different factors affect this process. The hybrid zone between the all black carrion crow (Corvus corone corone) and the grey and black hooded crow (Corvus c. READ MORE

  5. 3. Causes and consequences of niche differentiation between color morphs of pygmy grasshoppers

    Author : Einat Karpestam; Anders Forsman; Birgitta Tullberg; Linnéuniversitetet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; color polymorphism; visual predators; Tetrix subulata; differential habitat use; niche; thermoregulation; feeding preferences; stable isotopes; Evolutionary Biology; Evolutionsbiologi;

    Abstract : In this thesis, I used the color polymorphic pygmy grasshopper, Tetrix subulata, as a model system in order to investigate the degree of niche differentiation between alternative color morphs that are present within a single population. First, I hypothesized that individuals belonging to different color morphs differ in their innate food preference due to somewhat dissimilar physiology, and in their actual food consumption due in part to differential habitat use. READ MORE

  6. 4. Through the eyes of a woodpecker: Understanding habitat selection, territory quality and reproductive decisions from individual behaviour

    Author : Ola Olsson; Biodiversitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; reproductive success; territory quality; habitat selection; giving-up density; Bayesian processes; foraging; Picidae; lesser spotted woodpecker; Dendrocopos minor; conservation; Animal ecology; Djurekologi;

    Abstract : In this thesis I present some connections between foraging behaviour and reproductive success, time budget, tree species use, and habitat selection. The thesis is based upon both theoretical and empirical work. All empirical studies concern a south Swedish population of lesser spotted woodpeckers Dendrocopos minor, studied between 1990 and 1996. READ MORE

  7. 5. Habitat selection and breeding ecology of golden eagles in Sweden

    Author : Edward Moss; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

    Abstract : The red-listed Golden Eagle (Aquila chrysaetos) population is estimated between 1200-1400 reproductive individuals in Sweden. This population is unusual as eagles predominantly nest in trees unlike most others that prefer cliffs. READ MORE