Marine biology involves the study of different life forms in the ocean, both plant and animal. Scientists and individuals continue to show interest in the ocean since there are still so many things left undiscovered. Some parts of the saltwater environment remain unknown simply because human beings cannot access these readily. You have to know more about the hierarchy of the life forms and how each interact with each other and the environment.
Microscopic Beings
Microscopic life in the ocean is very diverse and is understood in the least sense by individuals. Viruses, for example, is rarely explored and considered. Phytoplankton’s function and role is understood better because of its vital position as the most numerous primary producers in the planet. Phytoplankton is grouped into cyanobacteria or blue or green algae or bacteria, diatoms, different kinds of algae like brown algae, red algae and green algae, euglenoids, cryptomonads, chlorophytes, dinoflagellates, prasinophytes and silicoflagellates.
Zooplankton is usually larger and may not be microscopic. Several protozoa are zooplankton, including radiolarians, dinoflagellates, foraminiferans and zooflagellates. Some of the beings are also phytoplankton, with the plant and animal type usually breaking down into very tiny organisms. Other zooplanktons can include arthropods, polychaetes, cnidarians, urochordates and annelids.
The Plants
There ocean has very diverse plant life. Microscopic photosynthetic algae provide a big portion of the photosynthetic output of the world compared to all the terrestrial forests. Majority of the niche occupied by sub plants on terrain are usually known as seaweeds that build kelp forests. The intertidal zone is an ideal place to find plant life in the ocean, where beach grass and mangroves may proliferate. These can function as habitat for other animals.
The Fishes
Fish has transformed several biological functions from other big organisms. Fish breathe by getting oxygen from the water through the gills. The fins function by stabilizing and propelling fish in the water. Some of the most popular fishes include clownfish, sardines, bottom fish, sharks, barracuda and ling cod. Fishes will thrive in different depths and parts of the ocean, depending on their need. Some will migrate to other regions depending on the current temperature, habitat and availability of food.
Reptiles, Birds and Mammals
There are many reptiles that live in the sea like sea snakes, saltwater crocodiles, sea turtles and marine iguanas. Majority of these reptiles have to come back to land to lay their eggs. Some of the extinct species like the ichthyosaurs transformed and no longer needs to return to land. Several seabirds are also present such as penguins, albatrosses and gulls. These spend most of their time in the ocean, while others prefer to stay inland.
There are mainly 5 kinds of marine mammals. The polar bear is considered a marine mammal since it greatly depends on the ocean. Cetaceans include toothed whales like porpoises and the sperm whale. The sea otter is part of the Family Mustelidae. Sirenians include the sea cow, manatee and dugong. Seals, walruses and sea lions are grouped as pinnipeds.