Search for dissertations about: "predation pressure"

Showing result 1 - 5 of 30 swedish dissertations containing the words predation pressure.

  2. 1. Why and how brain size evolves : Sociality, predation and allometry

    Author : Wouter van der Bijl; Niclas Kolm; Joah Madden; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; brain size; brain size evolution; encephalization; predation; predator inspection; sociality; animal contest; constraint; etologi; Ethology;

    Abstract : The evolution of the vertebrate brain has remained a topic of intense interest from biologists over many decades. Evolutionary biologists have seen it as an intriguing example of how the size and structure of a trait evolves across large phylogenies and under body size constraints, with both large shifts in deep evolutionary time and continuous smaller scale adaptation. READ MORE

  4. 2. The aquatic microbial food web and occurence of predation-resistant and potentially pathogenic bacteria, such as Francisella tularensis

    Author : Johanna Thelaus; Agneta Andersson; Mats Forsman; Farooq Azam; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; bacteria; protozoa; ecology; predation; nutrient-availability; microbial food web; model; predation-resistance; Francisella; reservoir; biofilm formation; Freshwater ecology; Limnisk ekologi;

    Abstract : All natural aquatic systems harbour a vast variety of microorganisms. In the aquatic microbial food web, the larger microorganisms (i.e. protozoa) feed on the smaller microorganisms (i. READ MORE

  5. 3. Environmental factors selecting for predation resistant and potentially pathogenic bacteria in aquatic environments

    Author : Peter Mathisen; Agneta Andersson; Johanna Thelaus; Mats Forsman; Anders Sjöstedt; Tron Frede Thingstad; Umeå universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Eutrophication; productivity; predation pressure; predation-resistant bacteria; pathogens; Francisella tularensis; adaptation; biomarker; oligotyping;

    Abstract : The long history of co-existence of bacteria and their protozoan predators in aquatic environments has led to evolution of protozoa resistant bacteria (PRB). Many of these bacteria are also pathogenic to humans. READ MORE

  6. 4. The importance of predation in benthic stream communities

    Author : Jonas Dahl; Biologiska institutionen; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Ekologi; Ecology; invertebrate predators; vertebrate predators; Predation; streams;

    Abstract : 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. READ MORE

  7. 5. Multiple stressors in rotifer communities: : Effects of predation, climate change, and brownification

    Author : Huan Zhang; Enhet akvatisk ekologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Climate change; community dynamic; brownification; heat wave; inducible defense; rotifer; plasticity; multiple stressors; Predation; prey;

    Abstract : Most organisms on Earth live in an environment where they are exposed to multiple pressures, including predation and climate change. In many aquatic ecosystems, organisms have to handle additional challenges such as brownification, co-occurring with climate warming. READ MORE