Young ISDR

The dynamics of phytoplankton communities are controlled by bottom-up (water physics and chemistry) and top-down (natural enemies) drivers. However, the relative importance and direction of these drivers on community compositions and relative abundances are not well established: they vary in time and space and also depend on trait-mediated physiological and ecological interactions. The goal of this project is to quantify the relative effects of interacting drivers on phytoplankton, within taxonomic and size-based categories. The PhD student will consider physiological and ecological processes (e.g. nutrient acquisition, growth rates, and food-web interactions) and their size-scaling properties to develop theoretical models of how physical forcing, competition for resources, and grazing from specialist or generalists shape: 1) size distributions of prey and predators, 2) size-abundance and other trait-abundance relationships of phytoplankton communities, and 3) abundan...

[From Algae-L] A two-year postdoctoral fellowship is available at Lund University, Sweden. Project description Microscopic organisms are widespread and many species have a cosmopolitan distribution. This pattern suggests that microorganisms (such as phytoplankton), in contrast to most larger organisms, have unlimited dispersal. Unlimited dispersal implies high migration rates and gene flow within a species, and consequently no opportunity for populations to differentiate. However, many studies show that phytoplankton populations are genetically highly differentiated. This implies limited gene flow despite high dispersal, posing a dispersal–differentiation paradox. Explanations to this paradox may include the importance of founding individuals (founder effects), and rapid local adaptation in phytoplankton. Within this project we will experimentally test these hypotheses using a model green algal system. Tasks The postdoctoral fellow will be involved in the resear...