Antarctic realm
Quick Summary
The Antarctic realm, also known as the Archinotic realm, encompasses the Antarctic continent, its subantarctic islands, and parts of southwestern New Zealand. While not a distinct, unmixed realm today, its existence is supported by shared species found in both New Zealand and South America, such as certain stoneflies, crustaceans, and freshwater snails. It's also plausible that the marsupial family Microbiotheriidae, now only in Chile, is a remnant of an ancient Antarctic connection.1
Antarctic waters are highly productive due to nutrient upwelling, supporting a rich food chain that begins with phytoplankton and zooplankton, forming the base diet for whales, seals, fish, and seabirds. Krill (Euphausia superba) is a crucial organism in this ecosystem, providing sustenance for larger marine animals. The fish species in Antarctic seas are highly endemic, with about 90 percent found nowhere else, indicating a long period of isolation for the continent. Native Antarctic mammals are exclusively marine, including various seals, porpoises, dolphins, and whales.2
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AntarcticaPlant life…will have an impact on Antarctica’s fragile ecosystem.
Read More…will have an impact on Antarctica’s fragile ecosystem.
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biogeographic regionAntarctic realmThe Antarctic, or Archinotic, realm encompasses the Antarctic continent, subantarctic islands, and elements of southwestern New Zealand. The existence of the realm—or rather of its ghost, because nowhere today does it exist in an umixed state—is justified by the common occurrence in New…
Read MoreThe Antarctic, or Archinotic, realm encompasses the Antarctic continent, subantarctic islands, and elements of southwestern New Zealand. The existence of the realm—or rather of its ghost, because nowhere today does it exist in an umixed state—is justified by the common occurrence in New…
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polar ecosystemThe Antarctic regionAntarctica has been isolated from other continental landmasses by broad expanses of ocean since early in the Paleogene Period, about 60 to 40 million years ago. Prior to its separation it existed, along with Australia, South America, peninsular India, and Africa, as part…
Read MoreAntarctica has been isolated from other continental landmasses by broad expanses of ocean since early in the Paleogene Period, about 60 to 40 million years ago. Prior to its separation it existed, along with Australia, South America, peninsular India, and Africa, as part…
Read More- polar ecosystemBiota of Antarctica
The terrestrial fauna consists of a few invertebrate species of protozoans, rotifers, nematodes, tardigrades, collembola (primitive wingless insects), and a species of mite. These life-forms are restricted mainly to moist beds of moss. The diversity of marine mammals and birds in the coastal areas and associated…
Read MoreThe terrestrial fauna consists of a few invertebrate species of protozoans, rotifers, nematodes, tardigrades, collembola (primitive wingless insects), and a species of mite. These life-forms are restricted mainly to moist beds of moss. The diversity of marine mammals and birds in the coastal areas and associated…
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