Marine life
Marine life, which is also known as sea life or ocean life, refers to all the marine organisms that live in salt water habitats, or ecological communities that encompass all aquatic animals, plants, algae, fungi, protists, single-celled microorganisms and associated viruses living in the saline water of marine habitats, either the sea water of marginal seas and oceans, or the brackish water of coastal wetlands, lagoons, estuaries and inland seas. As of 2023, more than 242,000 marine species have been documented, and perhaps two million marine species are yet to be documented. On average, researches described about 2,300 new marine species each year. The study of marine life spans into multiple fields, which is primarily marine biology, as well as biological oceanography.
By volume, oceans provide about 90% of the living space on Earth, and served as the cradle of life and vital biotic sanctuaries throughout Earth's geological history.