Sökning: "Theoretical ecology"

Visar resultat 1 - 5 av 148 avhandlingar innehållade orden Theoretical ecology.

  1. 1. The Evolution of Sexually Homologous Ornaments : Selection via Male Mate Choice Coinciding with Male-Male Competition in a Neotropical Mosquito

    Författare :Sandra South; Göran Arnqvist; Russell Bonduriansky; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; sexual selection; Sabethes cyaneus; Diptera; Culicidae; mosquito; mutual ornamentation; sexual selection; mutual mate choice; male mate choice; female ornament; ecology; animal behaviour; Ethology and behavioural ecology; Etologi och beteendeekologi; Animal Ecology; Zooekologi;

    Sammanfattning : The evolution of elaborate male ornaments via sexual selection is well-understood while the selective pressures acting on female ornaments remains unresolved. Female ornaments in species with strong sexual selection on the male homologue of the ornament were originally thought to result from an intersexual genetic correlation. LÄS MER

  3. 2. Predators in low arctic tundra and their impact on community structure and dynamics

    Författare :Maano Aunapuu; Tarja Oksanen; Ola Atlegrim; Oswald J. Schmitz; Umeå universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ecology; arthropods; coexistence; community dynamics; competition; food webs; hypothesis of exploitation ecosystems; intraguild predation; small mustelids; trophic cascades; Ekologi; Terrestrial; freshwater and marine ecology; Terrestisk; limnisk och marin ekologi; zooekologi; Animal Ecology;

    Sammanfattning : The abundance of predators and their impact on ecosystem dynamics is a vividly discussed topic in current ecology. In my studies, incorporating field observations, field experiments and theoretical modeling, I explored the importance of predators and predation in a low arctic tundra ecosystem in northern Norway. LÄS MER

  4. 3. Population divergence at small spatial scales : – theoretical and empirical investigations in perch

    Författare :Sara Bergek; Mats Björklund; Teija Aho; Sarah Goodacre; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Perca fluviatilis L.; Perch; Small scale genetic differentiation; Morphometrics; Isolation by distance; Dispersal; Gene flow; Microsatellites; Spatiotemporal stability; Barriers; Biology; Biologi; Terrestrial; freshwater and marine ecology; Terrestrisk; limnisk och marin ekologi; Animal Ecology; zooekologi;

    Sammanfattning : Genetically structured populations arise when gene flow between groups of individuals is hindered by geographical, behavioural or temporal barriers. The identification of such groups is important for understanding evolution and has large implications for conservation concern. LÄS MER

  5. 4. On the Ecology and Evolution of seed and Bud Dormancy

    Författare :Patric Nilsson; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; bet-hedging; overcompensation; herbivory; plant compensatory growth; bud dormancy; endosperm; seed provisioning; Seed dormancy; parent-offspring conflicts; Ecology; Ekologi; Botany; Botanik;

    Sammanfattning : This thesis considers the ecological and evolutionary significance of seed and bud dormancy. First, I present theoretical support to the idea that seed dormancy may evolve as a strategy to reduce sib competition in temporally homogeneous environments. LÄS MER

  7. 5. Evolutionary Resolutions of Conflicts with Mates and Offspring

    Författare :Roger Härdling; Biologiska institutionen; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Clutch evolution; Arms race; Idothea baltica; Evolutionary conflicts; Sexual conflicts; Parent-offspring; Endosperm; Ecology; Ekologi;

    Sammanfattning : In sexual conflicts and conflicts between parents and offspring, natural selection acts in different directions on the two sides. For example, males may be selected to achieve many mates, but female fitness may be maximised by monogamy. In this thesis I study the evolutionary outcome of these situations mainly by theoretical modelling. LÄS MER