Avancerad sökning

Hittade 4 avhandlingar som matchar ovanstående sökkriterier.

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

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

    Sammanfattning : 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. LÄS MER

  2. 2. Population-level consequences of variation

    Författare :Lena Wennersten; Anders Forsman; Olof Leimar; Deepa Agashe; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; colour polymorphism; diversity; establishment success; evolutionary changes; population-level consequences; predation risk; Tetrix subulata; variation; Evolutionary Biology; Evolutionsbiologi;

    Sammanfattning : Consequences of within population variation have recently attracted an increased interest in evolutionary ecology research. Theoretical models suggest important population-level consequences, but many of these predictions still remain to be tested. LÄS MER

  3. 3. Microevolution in pygmy grasshoppers

    Författare :Jon Tinnert; Anders Forsman; Anssi Laurila; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Evolutionary Biology; Evolutionsbiologi;

    Sammanfattning : Knowledge of how spatiotemporal environmental variation impacts ecological and evolutionary processes and contributes to genetic and phenotypic diversity of natural populations is key to understanding and protecting biological diversity. In this thesis I used pygmy grasshoppers to study how environmental conditions, population dynamics, dispersal and admixture may influence genetic structure and diversity, and to evaluate how functionally important variation may affect the ability of populations to cope with novel and changing habitats. LÄS MER

  4. 4. Evolution in changing environments revealed by fire melanism in pygmy grasshopper

    Författare :Magnus Karlsson; Anders Forsman; Karl Gotthard; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Evolution Melanism Polymorphism Pygmy grasshoppers; Biology; Biologi; Evolutionary Biology; Evolutionsbiologi;

    Sammanfattning : According to theory, genetic diversity can be maintained by environmental variation and the degree of genetic and phenotypic polymorphism may enhance the ability of populations to endure stress imposed by changing environments. In my thesis I used colour polymorphic pygmy grasshoppers (Tetrix subulata) as a model system to explore how environmental variation influenced genetic diversity. LÄS MER