When you visit a pond or the beach, what kinds of living things do you see in the water? Depending on the environment, you might find fish, frogs, crabs, insects, seaweed, or lily pads. Don’t let your eyes fool you, though… there’s a hidden world in water full of creatures too small to be seen!
To learn more about plankton, visit An Invisible Watery World or check out these amazing creatures up close in our Plankton Zoom Gallery.
Additional images from Wikimedia by Franco Folini.