Many plankton organisms have distinct, highly specialised forms, which developed in the course of evolution and play a significant role for the survival of the single species.
In particular, we examine mechanical aspects of unicellular organisms, such as diatoms and radiolarians, their predators as well as their impacts on ecosystems and evolution, our focus being on:
Functional morphology – The correlation between form and function of plankton organisms is a highly interesting topic. We particularly examine the impact of different geometries on the function of plankton shells as protection against mechanic attacks by crustaceans (copepods).
Material properties - Not only the morphology, but also the material properties of the examined structures (diatom shells) are very sophisticated and optimise the shells’ efficiency as mechanical protection. They are characterised by a high stability in spite of a relatively low density. We are working on obtaining more precise material data with advanced methods to analyse material properties and nanostructures.
Morphogenesis - The highly complex diatom shells are formed in hollow molds – the silica deposition vesicles (SDVs). It is not yet clear how the cell steers its structuring. What is known is that the interaction between cytoskeleton and boundary membrane thereby plays a significant role. It is, however, obscure which genomic segments are responsible for species-specific geometries. It is planned to explore this relation.
Biomineralization - The precipitation of silicate (in the case of diatoms and radiolarians) is caused within the SDVs by the consilience of different organic components with dissolved silicate. This process leads to the formation of the glass-like silicate and shall be examined including by manipulation of the conditions of growth.
Plankton ecology – The interaction between the individual groups of organisms shapes the composition of species and the manifestation of specific morphotypes in planktonic ecosystems. Among other things, we compare prognoses based on mechanic features with the effects of these characteristics in experiments, e. g. in feeding experiments with diatoms.
Evolution – The arms race between feeding tools and defensive structures (shells) crucially affects the genesis of species as well as the biodiversity of the groups of organisms involved. This process shall be increasingly examined in the manner of a simulation of evolution with the aid of genetic algorithms (e.g. evolutionary strategic optimization).