The evolution of modern eukaryotic phytoplankton
Paul G Falkowski1, Miriam E Katz, Andrew H Knoll
1Institute of Marine and Coastal Sciences, Rutgers University, 71 Dudley Road, New Brunswick, NJ 08540, USA. falko@imcs.rutgers.edu
Science (New York, N.Y.)
|July 17, 2004
Summary
Marine ecosystems rely on eukaryotic phytoplankton for structure and function. The Mesozoic Era saw the rise of dinoflagellates, coccolithophores, and diatoms, crucial for ocean organic matter flux.
Area of Science:
- Marine Biology
- Paleontology
- Oceanography
Background:
- Eukaryotic phytoplankton are vital for marine ecosystem structure and ecological function.
- Despite being numerically inferior to cyanobacteria, they drive significant organic matter flux.
- The rise of three major phytoplankton clades (dinoflagellates, coccolithophores, diatoms) occurred during the Mesozoic Era.
Purpose of the Study:
- To investigate the geological, geochemical, and biological factors behind the ecological rise of dinoflagellates, coccolithophores, and diatoms.
- To understand the evolutionary significance of secondary symbiosis in these key phytoplankton groups.
Main Methods:
- Review of geological records.
- Analysis of geochemical proxies.
- Examination of biological evolutionary pathways.
Main Results:
- The Mesozoic Era was a critical period for the diversification and ecological dominance of key phytoplankton groups.
- Secondary symbiosis, originating from an ancestral red alga, is a shared characteristic of these dominant clades.
- These phytoplankton groups significantly influenced ocean biogeochemistry and food webs.
Conclusions:
- The rise of dinoflagellates, coccolithophores, and diatoms fundamentally shaped modern marine ecosystems.
- Understanding their evolutionary history is key to comprehending ocean productivity and carbon cycling.
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