Single cell analysis in biological oceanography and its evolutionary implications

Historically single cell analysis techniques have been usedto supplement more traditional studies of primary production.The techniques have often been used as a surrogate for microscopicanalysis and to close a gap in sea truth coverage for remotesensing and other mapping activities. In the course of developmentfrom Coulter counting to flow cytometry/cell sorting, the instrumentsand techniques have become powerful tools for allometric andataxonomic analysis as well as the quantification of pigmentsand added metabolic stains and tagged reagents. The specificquestions we ask here are: Can flow cytometry-derived data beraised to a level to discern evolutionary direction and diversity/complexity?Can we account for changes in community structure based on allometricand ataxonomic relationships across major ocean boundaries?We present evidence from different approaches and use examplesfrom flow cytometry/cell sorting that address the causes ofvariation in cell size and chlorophyll fluorescence in phytoplankton.The horizon is rapidly expanding yet questions and limitationsof ocean study persist. We believe that a road of commonalityamong oceanographers, ecologists, modelers, microbiologists,molecular biologists, physiologists and paleontologists is needed.