Imagine if a fish at the market could tell you where it came from; what would it say? "I came from a world of drifters," says one fish in this video. The world of drifters is the world of zooplankton. Many zooplankton, like the fish, are tiny embryos and recently-hatched larvae that will grow into much bigger fish, squids, clams, crabs, worms, corals, starfish, and other organisms. Some, like copepods and krill, are small drifters for their entire lives. But some zooplankton, which comes from the Greek word for "wandering," are already large organisms that don't swim, but drift, such as jellyfish, comb jellies, and salps. The zooplankton are an incredibly important food source in the ocean, feeding animals as small as other (slightly larger) zooplankton and as large as a blue whale! See amazing footage of zooplankton in action in this video.