Plankton are a critically important food source and play an important role in the global carbon cycle. This cycle captures the sun’s energy and the atmosphere’s CO2 at the surface of the ocean and releases it to other organisms and other areas of the ocean.

Zooniverse’s Plankton Portal shows citizen scientists one of millions of plankton images taken by the In Situ Ichthyoplankton Imaging System (ISIIS), a unique underwater robot engineered at the University of Miami. ISIIS operates as an ocean scanner that casts the shadow of tiny and transparent oceanic creatures onto a very high-resolution digital sensor at very high frequency.

The dataset used for Plankton Portal comes a period of just three days in Fall 2010. In three days, researchers collected so much data that would take more than three years to analyze it themselves. That’s why they need help from citizen scientists. A computer will probably be able to tell the difference between major classes of organisms, such as a shrimp versus a jellyfish, but to distinguish different species within an order or family, that is still best done by the human eye.