GEOMAR  Hamer, Jorin

M. Sc. Jorin Hamer | RD 3 Marine Ecology | RU Experimental Ecology

Doctoral Researcher | Biodiversity | Topic 6

Jorin Hamer

Office
ENB Building 5
Room 1.307
Tel.: +49 431 600 1368
e-mail: jhamer(at)geomar.de

Address
GEOMAR
Helmholtz-Zentrum für Ozeanforschung
Wischhofstraße 1-3
24148 Kiel
Germany

Research Group "Biodiversity" PI: Dr. Birte Matthiessen

Research Focus

  • Bacteria-phytoplankton symbiosis
  • Maintenance of biodiversity
  • The role of biodiversity for the functioning of ecosystems

Project Participation

  • DynaSym: Shifts in bacteria-algae symbiotic interactions - effects on plankton community dynamics and properties (DFG research unit FOR5726; https://www.dynasym.uni-konstanz.de; 2024-2028)

  • DynaTrait II: Nutrient uptake-related trait variability and trade-offs - adaptive evolution and community functioning in competing phytoplankton species (DFG priority programme SPP 1704; https://www.dynatrait.de/en; 2018-2022)

Vita

Since 2024 - Doctoral researcher at GEOMAR as part of DFG research group DynaSym

Since 2020 - Scientist at GEOMAR in the Biodiversity group as part of the research unit Experimental Ecology

2020 - Master of Science, Kiel University, Germany (Master’s thesis: “Genotype sorting of two stably coexisting phytoplankton species in response to nutrient fluctuations”, GEOMAR Helmholtz Center for Ocean Research Kiel, Germany

2016 - Bachelor of Science, Oldenburg University, Germany (Bachelor’s thesis: “The circadian clock in Calanus finmarchicus - Relation to diel vertical migration”, Alfred Wegener-Institute for Polar and Marine research, Germany)

Publications

Matthiessen, B., Hattich, G.S.I., Pulina, S., Hansen, T., Reusch, T.B.H. and Hamer, J. (2025), Phytoplankton mean cell size and total biomass increase with nutrients are driven by both species composition and evolution of plasticity. Oikos, 2025: e10910. https://doi.org/10.1111/oik.10910

Hamer, J., Matthiessen, B., Pulina, S., & Hattich, G. S. I. (2022). Maintenance of Intraspecific Diversity in Response to Species Competition and Nutrient Fluctuations. Microorganisms, 10(1), 113. https://doi.org/10.3390/microorganisms10010113

Wahl, M., Werner, F.J., Buchholz, B., Raddatz, S., Graiff, A., Matthiessen, B., Karsten, U., Hiebenthal, C., Hamer, J., Ito, M., Gülzow, E., Rilov, G. and Guy-Haim, T. (2020), Season affects strength and direction of the interactive impacts of ocean warming and biotic stress in a coastal seaweed ecosystem. Limnol Oceanogr, 65: 807-827. https://doi.org/10.1002/lno.11350