Antarctic flora
Encyclopedia
Vascular plant
Vascular 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 Gondwana
Gondwana
In 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 Hemisphere
Southern Hemisphere
The 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 America
South America
South 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 Africa
Africa
Africa 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 Zealand
New Zealand
New 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...
, Australia
Australia
Australia , 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 Caledonia
New Caledonia
New 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 Kingdom
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...
that included southern South America, New Zealand, and some southern island groups. Good identified Australia as its own floristic kingdom, and included New Guinea
New Guinea
New 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 podocarps
Podocarpaceae
Podocarpaceae 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 drift
Continental drift
Continental 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 America
South America
South 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 Current
Antarctic Circumpolar Current
The 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 Neotropic
Neotropic
In 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 America
South America
South 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 Australasia
Australasia ecozone
The 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 Caledonia
New Caledonia
New 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...
, Tasmania
Tasmania
Tasmania 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...
, Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
, India
India
India , 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 Zealand
New Zealand
New 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 America
South America
South 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 America
South America
South 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...
, Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
, Africa
Africa
Africa 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...
, India
India
India , 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...
, Macaronesia
Macaronesia
Macaronesia 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...
, Australia
Australia
Australia , 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 Zealand
New Zealand
New 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 Cretaceous
Cretaceous
The 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 Cretaceous
Cretaceous
The 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.
Acacia
Acacia 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...
, Eucalyptus
Eucalyptus
Eucalyptus is a diverse genus of flowering trees in the myrtle family, Myrtaceae. Members of the genus dominate the tree flora of Australia...
, and Casuarina
Casuarinaceae
Casuarinaceae 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. Human
Human
Humans 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 plant
Woody plant
A 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 Podocarpaceae
Podocarpaceae
Podocarpaceae 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....
, Araucariaceae
Araucariaceae
Araucariaceae, 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 Cupressaceae
Cupressaceae
The 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 Proteaceae
Proteaceae
Proteaceae 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,...
, Griselinia
Griselinia
Griselinia 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, Cunoniaceae
Cunoniaceae
The 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...
, Atherospermataceae
Atherospermataceae
The 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 Winteraceae
Winteraceae
The 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 (Nothofagus
Nothofagus
Nothofagus, 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 (Fuchsia
Fuchsia
Fuchsia 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 Dicksonia
Dicksonia
Dicksonia 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 Luma
Luma
Luma 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 Myrtaceae
Myrtaceae
The 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 Eucryphia
Eucryphia
Eucryphia 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 Cunoniaceae
Cunoniaceae
The 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, Monimiaceae
Monimiaceae
Monimiaceae 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 Hedycarya
Hedycarya
Hedycarya 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 Tambourissa
Tambourissa
Tambourissa 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 Atherospermataceae
Atherospermataceae
The 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 Daphnandra
Daphnandra
Daphnandra 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:...
, Doryphora
Doryphora
Doryphora is a genus of plant in the family Atherospermataceae, or formerly Monimiaceae. It contains four species, two endemic to Australia.-Overview:...
and Laurelia novae-zelandiae
Laurelia novae-zelandiae
Laurelia 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 plant
Vascular plant
Vascular 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 lichen
Lichen
Lichens 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 moss
Moss
Mosses 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 liverwort
Marchantiophyta
The 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 antarctica
Deschampsia antarctica
Deschampsia antarctica is one of two flowering plants native to Antarctica, the other being Colobanthus quitensis ....
(Antarctic hair grass) and Colobanthus quitensis
Colobanthus quitensis
Colobanthus 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 Peninsula
Antarctic Peninsula
The 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 antarctici
Grimmia antarctici
Grimmia 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 antarctici
Schistidium antarctici
Schistidium 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 glaciale
Sarconeurum glaciale
Sarconeurum 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 KingdomAntarctic 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...
- Flora of ChileFlora of ChileThe 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 ZealandFlora of New ZealandThis 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 AustraliaFlora of AustraliaThe 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...