This image shows a colorful octopus larva as seen under a microscope. Many animals in the sea star their lives in a larval form such as this. Millions of tiny animal larva form part of the plankton that serves as the first link in the ocean food chain. Plankton provide food for many animals in the sea. Many species such as corals, sponges, worms, and echinoderms have developed methods to filter the plankton from the passing sea water. This image was captured by Matt Wilson and Jay Clark from the National Oceanic and Atmospheric Administration.