if fossils of an aquatic animal or plant are found in a place then that place used to be covered by water in the past
aquatic_ecosystem is water. find_underwater is aquatic_plant. aquarium is animal_container. find_underwater is not aquatic_plants. aquatic is plant. fish is aquatic_animal. find_underwater is aquatic_plants. find_underwater is not aquatic_plant. fish is aquatic_vertebrate. find_underwater is aquatic_life.