Overlap and discrepancies between ecotypes, genotypes and morphotypes of Antartic and Arctic nanofauna

Heterotrophic nanoflagellates are major consumers of bacteria in the polar regions and contribute significantly to the carbon flux from DOC via bacteria to larger organisms such as ciliates and metazoans. Heterotrophic flagellate biomass may form a significant part of the microbial biomass in the sea ice. According to our recent molecular biological and morphological studies of nanofauna, many morphotypes contain several genotypes with sometimes high evolutionary distances (p-distances of SSU rDNA).

To study the role of endemism in polar waters, we analyzed discrepancies and overlaps between morphotypes, genotypes and ecotypes of selected nanoflagellates to draw conclusions regarding the possible effects of changes in temperature on the sensitive Antarctic and Arctic ice biota. We took samples from Antarctic and Arctic sites, established cultures of nanoflagellates and analysed them combining morphological, molecular biological and ecological methods. We used new clonal cultures in addition to already established cultures of Antarctic and Arctic isolates to study the tolerance of single genotypes regarding temperature and salinity.

Scientists

Prof. Dr. Hartmut Arndt
Universität zu Köln
Zoologisches Institut / Allgemeine Ökologie


Dr. Frank Nitsche
Universität zu Köln
Zoologisches Institut / Allgemeine Ökologie

Research areas

King George Island, Jubany (South 62°, West 58°) and surroundings
Svalbard, NyAlesund (North 79°, East 15°) and surroundings

Research funding organisation

German Research Foundation

Project number: AR 288/8 1-2
Funding period: September 2006 - August 2008