The
Antarctic flora is a distinct community of
vascular plantVascular plants are those plants that have lignified tissues for conducting water, minerals, and photosynthetic products through the plant. Vascular plants include the clubmosses, Equisetum, ferns, gymnosperms and angiosperms...
s which evolved millions of years ago on the supercontinent of
GondwanaIn paleogeography, Gondwana , originally Gondwanaland, was the southernmost of two supercontinents that later became parts of the Pangaea supercontinent. It existed from approximately 510 to 180 million years ago . Gondwana is believed to have sutured between ca. 570 and 510 Mya,...
, and is now found on several separate areas of the
Southern HemisphereThe Southern Hemisphere is the part of Earth that lies south of the equator. The word hemisphere literally means 'half ball' or "half sphere"...
, including southern
South AmericaSouth America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
, southernmost
AfricaAfrica is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
,
New ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
,
AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and
New CaledoniaNew Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
. Based on the similarities in their flora, botanist Ronald Good identified a separate
Antarctic Floristic KingdomThe Antarctic Floristic Kingdom is a floristic region first identified by botanist Ronald Good , which includes most areas of the world south of 40°S latitude...
that included southern South America, New Zealand, and some southern island groups. Good identified Australia as its own floristic kingdom, and included
New GuineaNew Guinea is the world's second largest island, after Greenland, covering a land area of 786,000 km2. Located in the southwest Pacific Ocean, it lies geographically to the east of the Malay Archipelago, with which it is sometimes included as part of a greater Indo-Australian Archipelago...
and New Caledonia in the Paleotropical floristic kingdom, because of the influx of tropical Eurasian flora that had mostly supplanted the Antarctic flora.
Millions of years ago, Antarctica was warmer and much wetter, and supported the Antarctic flora, including forests of
podocarpsPodocarpaceae is a large family of mainly Southern Hemisphere conifers, comprising about 156 species of evergreen trees and shrubs. It contains 19 genera if Phyllocladus is included and if Manoao and Sundacarpus are recognized....
and southern beech. Antarctica was also part of the ancient supercontinent of Gondwanaland, which gradually broke up by
continental driftContinental drift is the movement of the Earth's continents relative to each other. The hypothesis that continents 'drift' was first put forward by Abraham Ortelius in 1596 and was fully developed by Alfred Wegener in 1912...
starting 110 million years ago. The separation of
South AmericaSouth America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
from Antarctica 30-35 million years ago allowed the
Antarctic Circumpolar CurrentThe Antarctic Circumpolar Current is an ocean current that flows from west to east around Antarctica. An alternative name for the ACC is the West Wind Drift. The ACC is the dominant circulation feature of the Southern Ocean and, at approximately 125 Sverdrups, the largest ocean 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
NeotropicIn biogeography, the Neotropic or Neotropical zone is one of the eight terrestrial ecozones. This ecozone includes South and Central America, the Mexican lowlands, the Caribbean islands, and southern Florida, because these regions share a large number of plant and animal groups.It is sometimes used...
(
South AmericaSouth America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
) and
AustralasiaThe Australasian zone is an ecological region that is coincident, but not synonymous , with the geographic region of Australasia...
, which were also former parts of Gondwana.
Some genus originated in Antarctic Flora are still a recognized major component of
New CaledoniaNew Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...
,
TasmaniaTasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
,
MadagascarThe Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
,
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
,
New ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
, and southern
South AmericaSouth America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
.
South AmericaSouth America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
,
MadagascarThe Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
,
AfricaAfrica is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
,
IndiaIndia , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
,
MacaronesiaMacaronesia is a modern collective name for several groups of islands in the North Atlantic Ocean near Europe and North Africa belonging to three countries: Portugal, Spain, and Cape Verde...
,
AustraliaAustralia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
,
New ZealandNew Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
, and
Antarctica were all part of the supercontinent Gondwana, which started to break up in the early
CretaceousThe Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
period (135-65 million years ago). India was the first to break away, followed by Africa, and then New Zealand, which started to drift north. By the end of the Cretaceous, South America and Australia were still joined to Antarctica. Paleontologist Gilbert Brenner identified the emergence of a distinct southern Gondwanan flora by the late
CretaceousThe Cretaceous , derived from the Latin "creta" , usually abbreviated K for its German translation Kreide , is a geologic period and system from circa to million years ago. In the geologic timescale, the Cretaceous follows the Jurassic period and is followed by the Paleogene period of the...
period in the cooler and humid southern hemisphere regions of Australia, southern South America, southern Africa, Antarctica, and New Zealand; it most resembled the flora of modern-day southern New Zealand. A drier northern Gondwanan flora had developed in northern South America and northern Africa.
Africa and India drifted north into the tropical latitudes, became hotter and drier, and ultimately connected with the Eurasian continent, and today the flora of Africa and India have few remnants of the Antarctic flora. Australia drifted north and became drier as well; the humid Antarctic flora retreated to the east coast and Tasmania, while the rest of Australia became dominated by
AcaciaAcacia is a genus of shrubs and trees belonging to the subfamily Mimosoideae of the family Fabaceae, first described in Africa by the Swedish botanist Carl Linnaeus in 1773. Many non-Australian species tend to be thorny, whereas the majority of Australian acacias are not...
, EucalyptusEucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
, and
CasuarinaCasuarinaceae is a family of dicotyledonous flowering plants placed in the order Fagales, consisting of 3 or 4 genera and approximately 70 species of trees and shrubs native to the Old World tropics , Australia, and the Pacific Islands...
, as well as xeric shrubs and grasses.
HumanHumans are the only living species in the Homo genus...
s arrived in Australia 50-60,000 years ago, and used fire to reshape the vegetation of the continent; as a result, the Antarctic flora, also known as the
Rainforest flora in Australia, retreated to a few isolated areas composing less than 2% of Australia's land area.
The
woody plantA woody plant is a plant that uses wood as its structural tissue. These are typically perennial plants whose stems and larger roots are reinforced with wood produced adjacent to the vascular tissues. The main stem, larger branches, and roots of these plants are usually covered by a layer of...
s of the Antarctic flora include conifers in the families
PodocarpaceaePodocarpaceae is a large family of mainly Southern Hemisphere conifers, comprising about 156 species of evergreen trees and shrubs. It contains 19 genera if Phyllocladus is included and if Manoao and Sundacarpus are recognized....
,
AraucariaceaeAraucariaceae, commonly referred to as araucarians, is a very ancient family of coniferous trees. It achieved its maximum diversity in the Jurassic and Cretaceous periods, when it was distributed almost worldwide...
and the subfamily Callitroideae of
CupressaceaeThe Cupressaceae or cypress family is a conifer family with worldwide distribution. The family includes 27 to 30 genera , which include the junipers and redwoods, with about 130-140 species in total. They are monoecious, subdioecious or dioecious trees and shrubs from 1-116 m tall...
, and angiosperms such as the families
ProteaceaeProteaceae is a family of flowering plants distributed in the Southern Hemisphere. The family comprises about 80 genera with about 1600 species. Together with the Platanaceae and Nelumbonaceae they make up the order Proteales. Well known genera include Protea, Banksia, Embothrium, Grevillea,...
,
GriseliniaGriselinia is a genus of seven species of shrubs and trees, with a highly disjunct distribution native to New Zealand and South America. It is a classic example of the Antarctic flora....
ceae,
CunoniaceaeThe Cunoniaceae is a family of 26 genera and about 350 species of woody plants in the Antarctic flora, with many laurifolia species with glossy leaves endemic to laurel forest habitat. The family is native to Australia, New Caledonia, New Guinea, New Zealand, southern South America, the Mascarene...
,
AtherospermataceaeThe Atherospermataceae, commonly known as the southern sassafrases, are a family of broadleaf evergreen trees and shrubs. The family includes 14 species in seven genera. The atherosperms are native to the southern hemisphere, with two species native to southern Chile and 12 species native to...
, and
WinteraceaeThe Winteraceae are a family of flowering plants. The family includes 120 species of trees and shrubs in 9 genera.The Winteraceae are a mostly southern-hemisphere family associated with the Antarctic flora, found in tropical to temperate climate regions of Malesia, Oceania, eastern Australia, New...
, and genera like southern beech (
NothofagusNothofagus, also known as the southern beeches, is a genus of 35 species of trees and shrubs native to the temperate oceanic to tropical Southern Hemisphere in southern South America and Australasia...
) and fuchsia (
FuchsiaFuchsia is a genus of flowering plants that consists mostly of shrubs or small trees. The first, Fuchsia triphylla, was discovered on the Caribbean island of Hispaniola in 1703 by the French Minim monk and botanist, Charles Plumier...
). Many other families of flowering plants and ferns, including the tree fern
DicksoniaDicksonia is a genus of tree ferns in the order Cyatheales. It is regarded as related to Cyathea, but is considered more primitive, dating back at least to the Jurassic and Cretaceous periods. The fossil record includes stems, pinnules, and spores....
, are characteristic of the Antarctic flora.
Flora of Antarctica
Palaeofloristic studies of the continent of
Antarctica show the ecological dominance of the angiosperms on the Antarctic continent and the Southern Hemisphere during the Late Cretaceous and the present day disjunct austral vegetation. Investigations of Upper Cretaceous and Early Tertiary sediments of Antarctica yield a rich assemblage of well-preserved fossil dicotyledonous angiosperm wood which provides evidence for the existence, since the Late Cretaceous, of temperate forests similar in composition to those found in present-day southern South America, New Zealand and Australia. It is suggested an paleobotanical habitat similar to the extant cool temperate Valdivian rainforests.
There are two conifer and at least seven angiosperm morphotypes recorded in the Antarctica palaeoflora. Cupressinoxylon Goeppert, which is the more common, and Podocarpoxylon Gothan represent the conifers. The angiosperm component includes two species of Nothofagoxylon one sppecies of
LumaLuma may refer to :* Luma , a genus of plants in the myrtle family* Amomyrtus luma, a species of tree in the myrtle family* Luma , a signal used in video technology* A star species from Super Mario Galaxy or Super Mario Galaxy 2....
, in
MyrtaceaeThe Myrtaceae or Myrtle family are a family of dicotyledon plants, placed within the order Myrtales. Myrtle, clove, guava, feijoa, allspice, and eucalyptus belong here. All species are woody, with essential oils, and flower parts in multiples of four or five...
genus, one species of
EucryphiaEucryphia is a small genus of trees or large shrubs of the Antarctic flora, native to the south temperate regions of South America and coastal eastern Australia. Traditionally placed in a family of their own, the Eucryphiaceae, more recent classifications place them in the Cunoniaceae. There are...
, in
CunoniaceaeThe Cunoniaceae is a family of 26 genera and about 350 species of woody plants in the Antarctic flora, with many laurifolia species with glossy leaves endemic to laurel forest habitat. The family is native to Australia, New Caledonia, New Guinea, New Zealand, southern South America, the Mascarene...
. Other two species assigned to genera Myrceugenelloxylon, Weinmannioxylon,
MonimiaceaeMonimiaceae is a family of flowering plants, which includes 150-220 species of shrubs and small trees in 18-25 genera. They are native to the southern hemisphere tropics and subtropics. The largest genus is Tambourissa, with 50 species in Madagascar, the Mascarene Islands, and the Comoros...
,
Hedycaryoxylon, subfamily Monimioideae, that exhibit anatomical features characteristic of Hedycaryoxylon and extant
HedycaryaHedycarya is a genus of trees and shrubs of the family Monimiaceae. Species occur in South East Asia, New Caledonia, Australia and Polynesia including New Zealand....
and
TambourissaTambourissa is a genus of plant in family Monimiaceae. It contains the following species :* Tambourissa cocottensis, Lorence* Tambourissa pedicellata, Baker...
, and Atherospermoxylon, erected for fossil woods of the Monimiaceae in the tribe Atherospermeae, now
AtherospermataceaeThe Atherospermataceae, commonly known as the southern sassafrases, are a family of broadleaf evergreen trees and shrubs. The family includes 14 species in seven genera. The atherosperms are native to the southern hemisphere, with two species native to southern Chile and 12 species native to...
in that they exhibit anatomical features similar to Atherospermoxylon and extant
DaphnandraDaphnandra is a genus of shrubs and trees in the family Atherospermataceae, or formerly Monimiaceae. The genus is endemic to Australia.There are six species, occurring in New South Wales and Queensland:...
,
DoryphoraDoryphora is a genus of plant in the family Atherospermataceae, or formerly Monimiaceae. It contains four species, two endemic to Australia.-Overview:...
and
Laurelia novae-zelandiaeLaurelia novae-zelandiae, also called Pukatea, is a large laurifolia evergreen tree, endemic to the forests of New Zealand . with so-called 'toothed' leaves and producing small flowers...
.
The continent of Antarctica itself has been later too cold and dry to support virtually any
vascular plantVascular plants are those plants that have lignified tissues for conducting water, minerals, and photosynthetic products through the plant. Vascular plants include the clubmosses, Equisetum, ferns, gymnosperms and angiosperms...
s for millions of years. The chilling temperature, lack of sunlight, little rainfall, inferior soil quality and lack of moisture account, due to the inability of the plants to absorb water available by to be in the form of ice, for scanty vegetation . Its extant flora presently consists of around 250
lichenLichens are composite organisms consisting of a symbiotic organism composed of a fungus with a photosynthetic partner , usually either a green alga or cyanobacterium...
s, 100
mossMosses are small, soft plants that are typically 1–10 cm tall, though some species are much larger. They commonly grow close together in clumps or mats in damp or shady locations. They do not have flowers or seeds, and their simple leaves cover the thin wiry stems...
es, 25-30
liverwortThe Marchantiophyta are a division of bryophyte plants commonly referred to as hepatics or liverworts. Like other bryophytes, they have a gametophyte-dominant life cycle, in which cells of the plant carry only a single set of genetic information....
s, and around 700 terrestrial and aquatic algal species. Two flowering plants,
Deschampsia antarcticaDeschampsia antarctica is one of two flowering plants native to Antarctica, the other being Colobanthus quitensis ....
(Antarctic hair grass) and
Colobanthus quitensisColobanthus quitensis is one of the two flowering plants found in the Antarctic region. It occurs on the continental edge, as well as the South Orkney Islands and the South Shetland Islands...
(Antarctic pearlwort), are found on the northern and western parts of the
Antarctic PeninsulaThe Antarctic Peninsula is the northernmost part of the mainland of Antarctica. It extends from a line between Cape Adams and a point on the mainland south of Eklund Islands....
. Species of moss endemic to Antarctica include
Grimmia antarcticiGrimmia antarctici is a species of moss that grows in areas of Antarctica such as the Windmill Islands. It lives in areas that are not icy, especially on the northern peninsula. Unusually high levels of carbon dioxide have been found in air surrounding this species of moss.-References:**...
,
Schistidium antarcticiSchistidium antarctici is a species of moss found in Antarctica. It lives in compact clumps that are yellowish green at the top and brownish black at the bottom. It grows on both soil and rocks....
, and
Sarconeurum glacialeSarconeurum glaciale is a species of moss in Antarctica. It lives in Ross Island and Southern Victoria Land in Antarctica, and on Tierra del Fuego.-References:**...
.
See also
- Antarctic Floristic Kingdom
The Antarctic Floristic Kingdom is a floristic region first identified by botanist Ronald Good , which includes most areas of the world south of 40°S latitude...
- Flora of Chile
The native flora of Chile is characterized by a higher degree of endemism and relatively fewer species compared to the flora of other countries of South America...
- Flora of New Zealand
This article relates to the flora of New Zealand, especially indigenous strains. New Zealand's geographical isolation has meant the country has developed a unique variety of native flora...
- Flora of Australia
The flora of Australia comprises a vast assemblage of plant species estimated to over 20,000 vascular and 14,000 non-vascular plants, 250,000 species of fungi and over 3,000 lichens...