Sökning: "Predator"

Visar resultat 6 - 10 av 192 avhandlingar innehållade ordet Predator.

1. 6. Antipredator defence in butterflies

   Författare :Martin Olofsson; Christer Wiklund; Graeme Ruxton; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Antipredator defence; Bird; Crypsis; Predator; Predator-prey interaction; Prey-attack behavior; Butterfly; Deimatic behavior; Eyespots; Startle display; zoologisk ekologi; Animal Ecology;

   Sammanfattning : Predation exerts a potent selection mechanism and has resulted in a suite of antipredation adaptations encompassing morphological and behavioral traits in prey. In butterflies, several such traits appear to be directed towards birds which are considered as one of their major predators. LÄS MER

3. 7. Anthropogenic impact on predator guilds and ecosystem processes : Apex predator extinctions, land use and climate change

   Författare :Marianne Pasanen Mortensen; Bodil Elmhagen; Francisco Palomares; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mesopredators; apex predators; top-down; bottom-up; interspecific killing; red fox; Eurasian lynx; grey wolf; wolverine; productivity; winter severity; cropland; zoologisk ekologi; Animal Ecology;

   Sammanfattning : Humans affect ecosystems by changing species compositions, landscape and climate. This thesis aims to increase our understanding of anthropogenic effects on mesopredator abundance due to changes in apex predator status, landscape and climate. LÄS MER

4. 8. Predator psychology and mimicry evolution - a theoretical analysis

   Författare :Alexandra Balogh; Olof Leimar; Michael Speed; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Müllerian mimicry; two-step evolution; gradual evolution; mutualism; predator psychology; Ethology and behavioural ecology; Etologi och beteendeekologi; etologi; Ethology;

   Sammanfattning : The evolution of Müllerian mimicry depends on many factors, among which predator psychology is the most important one. Predator avoidance learning, generalization and discrimination are primary selective agents during the evolutionary process. LÄS MER

5. 9. Psychotropic Pharmaceuticals in Aquatic Systems: An Ecological Perspective

   Författare :Melanie Hedgespeth; Enhet akvatisk ekologi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; ecotoxicology; aquatic; trophic level; pharmaceutical; SSRI; beta-blocker; sertraline; fluoxetine; propranolol; fish; daphnia; snail; predator; prey; behavior; life history; multiple stressor;

   Sammanfattning : Psychotropic pharmaceuticals have been shown to exert a variety of sublethal effects on non-target organisms, even at low concentrations found in the environment (ng/L to µg/L); hence, the aim of my research has been to determine the individual-level effects of psychotropic pharmaceuticals (the selective serotonin reuptake inhibitors sertraline and fluoxetine, and the β-blocker propranolol) on behavioral and life history traits in freshwater organisms. Further, this research was directed towards assessing the potential large-scale impacts of these effects on population growth and predator-prey interactions (with community-level implications) via the application of traditional, ecological concepts and models. LÄS MER

7. 10. Predator-Prey systems and Applications

   Författare :Torsten Lindström; Luleå tekniska universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Mathematics; Matematik; Mathematics;

   Sammanfattning : .... LÄS MER