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Adjunct Senior Research Scientist
Lamont-Doherty Earth Observatory
Biology and Paleo Environment
4 Marine Biology
61 Route 9W - PO Box 1000
(845) 365-8452
(845) 365-8150


Fields of interest: 
Physiological Ecology of Eukaryotic Microbes in aquatic and terrestrial environments

Eukaryotic microbes are single-celled organisms that have a true nucleus and cytoplasmic membranous organelles that distinguish them from bacterial microbes lacking a true nucleus.  Eukaryotic microbes include the photosynthetic algae and protozoa that together form the Protista.  My research focuses particularly on the amoeboid protists, their ecological relationship to other protists, environmental physical and biogeochemical variables, and their  role in food webs, habitat abundance and diversity, and role in carbon budgets of ecosystems (that is how carbon compounds are acquired as food and the fate of the carbon during transfer up the food chain). Eukaryotic microbes are also a significant source of respiratory carbon dioxide and at higher latitudes their high densities (astronomical numbers across large geographic regions) can yield a significant amount of carbon dioxide to the atmosphere, especially if there is increased warming in the polar regions. This respiratory source, along with a larger amount from bacteria, can contribute to atmospheric build-up of carbon dioxide and enhance global warming due to the so-called greenhouse effect. In the course of my ecological research, I also contribute papers on the fine structure (electron microscopic structures) and morphology (light microscopic features) of protists, especially any new species that are identified in our samples (including c. a dozen new genera and species).  Among the aquatic  environments where I have worked are the Hudson River, Firth of Clyde in Scotland, coastal Berumda, and the mangrove marshes of south Florida. Amoeboid protists also harbor pathogenic or potentially pathogenic bacteria that cause human diseases, and I have collaborated with colleagues at the College of Physicians and Surgeons examining the cellular biology and fine structural evidence that explain how amoeboid protists ingest and eventually accommodate these pathogens within their cells. 

List of degrees from highest to lowest:
Doctorate in Biology and Education
Washington University, St. Louis
Washington University, Graduate Institute of Education, St. Louis
Washington University, St. Louis
Honors & Awards: 
Bermuda Biological Station Award for Marine Science Research (Marine Biomineralizing Protista) - 1979.
Diatom Species: Cocconeis Andersonii (Reimer and Lee) named in honor of the research contributions by O. R. Anderson to Protistology and symbiosis.
Medal of the Paleontological Society of Japan, Sendai Japan - 1999

Lamont Projects:

Referenced in the Following News Items:

Selected Publications:

The Role of Soil Microbial Communities in Soil Carbon Processes and the Biogeochemical Carbon Cycle Anderson, O. Roger Soil Carbon: Types, Management Practices and Environmental Benefits (2013)
The fate of organic sources of carbon in moss-rich tundra soil microbial communities: A laboratory experimental study Anderson, O. Roger Eukaryotic Microbiology Volume: 59 Issue: 6 p.: 564-570 (2012)
The role of amoeboid protists and the microbial community in moss-rich terrestrial ecosystems: Biogeochemical implications for the carbon budget and carbon cycle, especially at higher latitudes Anderson, O. R. Journal of Eukaryotic Microbiology May-Jun Volume: 55 Issue: 3 p.: 145-150 (2008) DOI 10.1111/j.1550-7408.2008.00319.x
A seasonal study of the carbon content of planktonic naked amoebae in the hudson estuary and in a productive freshwater pond with comparative data for ciliates Anderson, O. R. Journal of Eukaryotic Microbiology Jul-Aug Volume: 54 Issue: 4 p.: 388-391 (2007) DOI 10.1111/j.1550-7408.2007.00276.x
Legionella effectors that promote nonlytic release from protozoa Chen, J.; de Felipe, K. S.; Clarke, M.; Lu, H.; Anderson, O. R.; Segal, G.; Shuman, H. A. Science Feb 27 Volume: 303 Issue: 5662 p.: 1358-1361 (2004)
Naked amoebas and bacteria in an oil-impacted salt marsh community Anderson, O. R.; Gorrell, T.; Bergen, A.; Kruzansky, R.; Levandowsky, M. Microbial Ecology Oct Volume: 42 Issue: 3 p.: 474-481 (2001)
Three new limax amoebae isolated from marine surface sediments: Vahlkampfia caledonica n sp, Saccamoeba marina n sp, and Hartmannella vacuolata n sp Anderson, O. R.; Rogerson, A.; Hannah, F. Journal of Eukaryotic Microbiology Jan-Feb Volume: 44 Issue: 1 p.: 33-42 (1997)