Doctoral Researcher Positions in the RTG R3

Fully funded doctoral researcher postions are available for the topics:

Ecological modelling and data analysis investigating the regime shift in the phytoplankton community in Upper Lake Constance

Eco-evolutionary dynamics of viruses, their hosts and competitors

For the first step of the application process, please send the following documents as single PDF file to Dr. Tina Romer,, coordinator of the Research Training Group R3. 

  • a curriculum vitae
  • a motivation letter detailing how you will fit into the Research Training Group R3
  • list of publications, if applicable
  • certificates of education
  • two letters of recommendation

The application process is open until the position is filled.

Doctoral researcher positions funded by the DFG are available for the following research topics:

1: Rapid evolution and resilience of lake communities

Topic/Questions: The project aims to test for the role of rapid evolution of species interaction in response to environmental changes for the reversibility of aquatic communities.

Work: The doctoral researcher will work with isolates of plankton from sediment cores and run microcosm experiments with aquatic communities consisting of algae species and consumers such as rotifers and viruses.

PIs:   Lutz Becks



Requirements: Master in Biology, Ecology or Limnology; experience in working with plankton and maintaining microcosms will be advantageous.

2: Reversibility and changing baselines in aquatic microcosm communities

Topic/Questions: The project aims to test whether reversibility of aquatic communities after an environmental perturbance (e.g. a phase of increased nutrient levels or of increased temperatures) is affected by a second change (e.g. by a new species that invaded the community).

Work: The doctoral researcher will do microcosm experiments in which aquatic communities consisting of multiple algae species will be exposed to various environmental treatments.

PIs: Mark van Kleunen & Lutz Becks



Requirements: Master in Biology, Ecology or Limnology; experience with maintaining microcosms will be advantageous.

3: Resilience of Lake Constance to the establishment of Planktothrix rubescens blooms and potential implications of a breakdown of this resilience

Topic/Questions: (i) Potential causes of bloom formation and bloom decay of P. rubescens: comparison between Lake Ammer and Lake Constance, (ii) Mechanisms of competitive advantage and persistence of P. rubescens, (iii) Implications of P. rubescens toxins for higher trophic levels.

Work: The doctoral researcher will establish and utilize long-term records of eDNA in sediment cores from Lake Ammer and Lake Constance, conduct mesocosm and/or chemostat experiments for process identification, and use field data on toxin distributions within food webs containing P. rubescens.

PIs: Frank Peeters & Laura Epp



Requirements: Master in Biology, Ecology or Limnology; Experiences in plankton research, paleolimnological methods, eDNA, and statistical data analysis are an asset.

4: Evaluating the role of sulfolipids for the Lake Constance phytoplankton

Topic/Questions: The growth of phytoplankton in Lake of Constance is limited predominantly by the limited amounts of available dissolved inorganic phosphate. However, eukaryotic phytoplankton and cyanobacteria (the phytoplankton collectively) have the ability to decrease their cellular phosphorus demand. One of these mechanisms involves non-phosphorus membrane lipids that can substitute for phospholipids, that is, biosynthesis of sulfolipids (sulfoquinovosyl diacylglycerols, SQDGs). Until today, there is very little information available about SQDGs and the “sulfur-for-phosphorus” strategy of freshwater phytoplankton, particularly not for the total phytoplankton community of oligotrophic Lake of Constance.

Work: The doctoral researcher will establish a first, fundamental understanding of the role and importance of SQDGs for the phytoplankton in oligotrophic Lake Constance, when addressing both the total plankton community in the lake during its annual succession (as accessed by filtration) and axenic cultures in the lab of selected, Lake-Constance relevant phytoplankton species (algae and cyanobacteria) and individual heterotrophic bacterial strains. Mind that the project will involve considerable analytical chemistry (e.g., HPLC-MS/MS).

Requirements: We are looking for a highly talented and motivated student from all around the world, with a Master in Biology, Chemistry, Ecology or Limnology and proven experience in analytical chemistry (HPLC-MS/MS), and/or plant/algae physiology, microbiology, phytoplankton ecology.

PIs: David Schleheck, Dieter Spiteller, Peter Kroth and Dominik Martin-Creuzburg

5: Competition between cladoceran species during eutrophication and oligotrophication of Lake Constance

Topic/Questions: The project will investigate competition (and apparent competition) between small cladoceran species (Bosmina spp., Diaphanosoma brachyurum, Daphnia cucullata) in different environments (regarding food quantity, quality and invertebrate predators) in the light of modern competition theory.

Work: The doctoral researcher will run single-species experiments and multiple species experiments in order to predict competition from single-species experiments. In addition, she/he will analyze time series to study the dynamics of these species in Lake Constance.

PIs: Dietmar Straile, Dominik Martin-Creuzburg & Lutz Becks


Requirements: Master in Biology, Ecology or Limnology

6: Reproduction and first feeding of whitefish – highly influenced by climate change?

Topic/Questions: The project aims at investigating temperature-dependent whitefish spawning phenology and forecasting consequences for early food synchrony and the implications for successful recruitment. Based on findings, implications for fishery management actions like cold incubation of eggs should also be evaluated.

Work: The PhD candidate will use a combination of field work (analysis of zooplankton composition, monitoring of whitefish recruitment and development of the eggs in nature, etc.), laboratory and predictive modeling (analysis of available and experimentally collected data to predict spawning and hatching times)

PIs: Alexander Brinker, Dietmar Straile



Requirements: Master in Biology, Ecology or Limnology or Ecological Modelling; experience in ecological modelling

7: Analyses of past climate and anthropogenic impact on Lake Constance biota using sedimentary ancient DNA

Topic/Questions: The project will investigate sediment core DNA from Lake Constance, reaching back multiple millenia in order to trace the effects of human impact and climatic changes throughout this time. We will address the following questions: 1) How stable was the lacustrine ecosystem of Lake Constance in preceding centuries compared to the 20th century, and have patterns of response, resilience and reversibility changed?        2) Were earlier periods of change in lacustrine community composition related to changes in terrestrial ecosystems and human presence? 3) Were these changes driven by human land use or by climate?

Work: The doctoral researcher will analyze DNA extracted from dated sediment cores of Lake Constance and retrieve detailed information on a variety of aquatic and terrestrial organisms. The work will comprise DNA extraction, metabarcoding techniques as well as non-PCR based approaches to obtain NGS sequencing data. Biotic records will be compared to archaeological and historical records, as well as existing paleoclimate records of the area.

PIs: Laura Epp, Mark van Kleunen & David Schleheck



Requirements: Master in Biology, Ecology or Limnology; Experience with next generation sequencing data acquisition and analysis, as well as statistical data analyses. Experience with environmental DNA and/or ancient DNA are an asset, as is reading knowledge of German, in order to access older historical and archeological literature.

8: A comparative approach of diatom/bacteria interactions in biofilms and phycospheres

Work: Photoautotrophic biofilms and phycospheres are structures of carbohydrates surrounding benthic and pelagic algal cells, respectively. In a comparative approach, this project will study the role of diatom/bacteria interactions from Lake Constance and their role for determining algal responses to changing conditions. While biofilm model systems have already been established, new phycosphere model systems will be developed by isolation of diatoms and their associated bacteria.       

PIs: Peter Kroth, Dieter Spiteller & David Schleheck

9: Mixotrophy as a consequence of reoligotrophication?

Topic/Questions: The project aims at a molecular characterization of the role of mixotrophic algae in Lake Constance

Work: The doctoral researcher will study genetic and physiological properties of mixotrophic algae and the relation of phagotrophy and photosynthesis to reveal metabolic properties of the impact of these algae during re-oligotrophication of Lake Constance. Furthermore the advantages of mixotrophic strategies will be studied by competition experiments, metatranscriptomic approaches and community composition analysis.

PIs: Peter Kroth, David Schleheck, Lutz Becks & Frank Peeters

All applications and supporting materials (motivation letter including motivation to become part of the RTG, ranking of 3 preferred projects from the project list, curriculum vitae including degree certificates, abstract of master thesis, two letters of recommendation) have to be submitted in English via the Online Application Portal including reference number 2019/263

The application process is open until  positions are filled.