Sökning: "vertebrate predators"
Visar resultat 1 - 5 av 7 avhandlingar innehållade orden vertebrate predators.
1. The importance of predation in benthic stream communities
Sammanfattning : There has been considerable debate whether or not predators has any significant effects on prey densities in streams. This thesis examines the importance of predation in stream communities. I have conducted both field and laboratory studies where I have studied how both vertebrate and invertebrate predators affects benthic prey. LÄS MER
2. Predators in low arctic tundra and their impact on community structure and dynamics
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
3. On the protective value of conspicuous eyespots in Lepidoptera
Sammanfattning : Eyespots, circular patterns which resemble the general appearance of the vertebrate eye, are widespread throughout the animal kingdom and are for example, commonly found on the wings of butterflies where they have been proposed to confer protection against predation. However, empirical evidence of the adaptive value of eyespots, as well as knowledge of butterfly behaviour under the threat of predation, is scarce. LÄS MER
4. 100 million years of shark macroevolution : A morphometric dive into tooth shape diversity
Sammanfattning : Few vertebrate clades exhibit the evolutionary longevity and versatility of sharks, which constitute nearly half of all current chondrichthyan biodiversity and represent an ecological diversity of mid-to-apex trophic-level predators in both marine and freshwater environments. The rich fossil record of shark teeth from Mesozoic and Cenozoic rocks also makes the group amenable to large-scale quantitative analyses. LÄS MER
5. Defence on Demand : A physiological perspective on phenotypic plasticity in anti-predator traits
Sammanfattning : Almost all species face some degree of predation risk, and, hence, evolution has produced a plethora of anti-predator defences. However, anti-predator strategies require resources, and the prevailing risk of becoming prey is influenced by many factors and rarely constant across time and space. LÄS MER