In the ocean
Life within the ocean evolved 3 billion years prior to life on land. Both the depth and the distance from shore strongly influence the biodiversity of the plants and animals present in each region.Lifeforms native to the ocean include:
Fish;Radiata, such as jellyfish (Cnidaria),Cetacea, such as whales, dolphins, and porpoises;Cephalopods, such as octopus and squid;
Crustaceans, such as lobsters, clams, shrimp, and krill Marine worms;
Plankton; and Echinoderms, such as brittle stars, starfish, sea cucumbers, and sand dollars.In addition, many land animals have adapted to living a major part of their life on the oceans. For instance, seabirds are a diverse group of birds that have adapted to a life mainly on the oceans. They feed on marine animals and spend most of their lifetime on water, many only going on land for breeding. Other birds that have adapted to oceans as their living space are penguins, seagulls and pelicans. Seven species of turtles, the sea turtles, also spend most of their time in the oceans.