When Victor Hensen deployed the first true plankton net in 1887, he and his colleagues were attempting to answer three fundamental questions: What planktonic organisms are present in the ocean? How many of each type are present? How does the plankton’s composition change over time? Although answering these questions has remained a central goal of oceanographers, the sophisticated tools available to enumerate planktonic organisms today offer capabilities that Hensen probably could never have imagined.

Benfield, M.C., P. Grosjean, P.F. Culverhouse, X. Irigoien, M.E. Sieracki, A. Lopez-Urrutia, H.G. Dam, Q. Hu, C.S. Davis, A. Hansen, C.H. Pilskaln, E.M. Riseman, H. Schultz, P.E. Utgoff, and G. Gorsky. 2007. RAPID: Research on Automated Plankton Identification. Oceanography 20(2):172–187, https://doi.org/10.5670/oceanog.2007.63.

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