Study of the life in the ocean, including fish, sea mammals, crustaceans, shellfish, and plankton. The marine biologist examines the physiology, ecology, distribution, life cycle, diseases, and migration of ocean organisms. He will also examine the complex effects of pollution. The skilled marine biologist will be an expert on the classification of sea life and will be able to determine how closely two species are related and in which ocean environment they normally belong. This skill will also allow him to properly manage sea-farming activities.