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90°00′S 0°00′W / 90.000°S -0.000°E / -90.000; -0.000

The Antarctic realm is one of eight terrestrial biogeographic realms. The ecosystem includes Antarctica and several island groups in the southern Atlantic and Indian oceans. The continent of Antarctica is so cold that it has supported only 2 vascular plants for millions of years, and its flora presently consists of around 250 lichens, 100 mosses, 25–30 liverworts, and around 700 terrestrial and aquatic algal species, which live on the areas of exposed rock and soil around the shore of the continent. Antarctica's two flowering plant species, the Antarctic hair grass (Deschampsia antarctica) and Antarctic pearlwort (Colobanthus quitensis), are found on the northern and western parts of the Antarctic Peninsula. Antarctica is also home to a diversity of animal life, including penguins, seals, and whales.

Several Antarctic and sub-Antarctic island groups are considered part of the Antarctic realm, including Bouvet Island, the Crozet Islands, Heard Island, the Kerguelen Islands, the McDonald Islands, the Prince Edward Islands, the South Georgia Group, the South Orkney Islands, the South Sandwich Islands, and the South Shetland Islands. These islands have a somewhat milder climate than Antarctica proper, and support a greater diversity of tundra plants, although they are all too windy and cold to support trees.

Antarctic krill is the keystone species of the ecosystem of the Southern Ocean, and is an important food organism for whales, seals, leopard seals, fur seals, crabeater seals, squid, icefish, penguins, albatrosses and many other birds. The ocean there is so full of phytoplankton because water rises from the depths to the light-flooded surface, bringing nutrients from all oceans back to the photic zone.

On August 20, 2014, scientists confirmed the existence of microorganisms living 800 metres (2,600 feet) below the ice of Antarctica.

History

Millions of years ago, Antarctica was warmer and wetter, and supported the Antarctic flora, including forests of podocarps and southern beech. Antarctica was also part of the ancient supercontinent of Gondwanaland, which gradually broke up by continental drift starting 110 million years ago. The separation of South America from Antarctica 30–35 million years ago allowed the Antarctic Circumpolar Current to form, which isolated Antarctica climatically and caused it to become much colder. The Antarctic flora subsequently died out in Antarctica, but is still an important component of the flora of southern Neotropical (Latin America and the Caribbean) and Australasian realms, which were also former parts of Gondwana.

Some botanists recognize an Antarctic Floristic Kingdom that includes Antarctica, New Zealand, and parts of Temperate South America where the Antarctic Flora is still a major component.

Ecoregions

The Antarctic realm is divided into 17 tundra ecoregions:

References

1. Fox, Douglas (August 20, 2014). "Lakes under the ice: Antarctica's secret garden". Nature. 512 (7514): 244–246. Bibcode:2014Natur.512..244F. doi:10.1038/512244a. PMID 25143097.
2. Mack, Eric (August 20, 2014). "Life Confirmed Under Antarctic Ice; Is Space Next?". Forbes. Retrieved August 21, 2014.
3. Eric Dinerstein, David Olson et al. (2017). An Ecoregion-Based Approach to Protecting Half the Terrestrial Realm, BioScience, Volume 67, Issue 6, June 2017, Pages 534–545, https://doi.org/10.1093/biosci/bix014

Bibliography

• Terauds, A; Chown, SL; Morgan, F; Peat, HJ; Watts, D; et al. (2012). "Conservation biogeography of the Antarctic". Diversity and Distributions. 18 (7): 726–741. doi:10.1111/j.1472-4642.2012.00925.x. hdl:10019.1/120035.
• Life in the Freezer, a BBC television series on life on and around Antarctica
• Biodiversity at Ardley Island, South Shetland archipelago, Antarctica
• Deep Sea Foraminifera – Deep Sea Foraminifera from 4400m depth, Weddell Sea – an image gallery of hundreds of specimens and description
• Aliens in Antarctica; Visitors carry unwelcome species into a once pristine environment Archived 2012-05-10 at the Wayback Machine May 5, 2012 Science News

v t e Antarctica
Geography	Antarctic sea ice Climate Climate change Heat waves Ice shelves Geology Glaciers Mountains Tundra Volcanoes Regions Biogeographic realm Antarctic Peninsula East Antarctica ice sheet shield Extreme points Floristic Kingdom Islands South Pole South magnetic pole West Antarctica ice sheet Bodies of Water Antarctic/Southern Ocean Lake CECs Lake Mercer Lake Vostok List of rivers McMurdo Sound Ross Sea Weddell Sea Life Flora Microorganisms Wildlife Birds Mammals Krill
History	Expeditions Heroic Age World War II Colonization COVID-19 pandemic Years
Politics	Council of Managers of National Antarctic Programs Military activity National programs Territorial claims Treaty System
Society	Antarctica Day Antarctic English Crime Demographics Economy Field camps Firefighting Flags Gateway cities Midwinter Day Protected areas Religion Research stations Telecommunications Time Tourism Transport Women
Famous explorers	Roald Amundsen Richard E. Byrd Douglas Mawson Ui-te-Rangiora (legendary) James Clark Ross Robert Falcon Scott Ernest Shackleton
Category Commons Index

• Antarctic realm
• Biogeographic realms
• Biogeography
• Phytogeography