Geographic Features Don't "Live" in the Ocean—But These Organisms Do

Geographic features (mountains, valleys, plains, trenches, ridges) are physical landforms, not living organisms. They exist in the ocean but do not "live" there.

What does live in the ocean is an astonishing diversity of marine life across every trophic level and habitat:

• Plankton: Phytoplankton (photosynthetic), zooplankton (animal drifters) — base of food web.
• Nekton (swimmers): Fish (tuna, salmon, lanternfish), cetaceans (whales, dolphins), pinnipeds (seals, sea lions), sea turtles, squid, sharks.
• Benthos (seafloor dwellers): Corals, sponges, crustaceans (crabs, lobsters), mollusks (clams, octopus), echinoderms (sea stars, urchins), worms.
• Seabirds: Albatrosses, petrels, penguins, gannets, frigatebirds — marine-adapted.
• Microbes: Bacteria, archaea, viruses — drive biogeochemical cycles.

From the sunlit euphotic zone to the hadal trenches (11 km deep), life occupies every cubic meter. The ocean is 99% of Earth's habitable volume—and it's all alive.