The
Palearctic or
Palaearctic is one of the eight
ecozoneAn ecozone is the broadest biogeographic division of the Earth's land surface, based on distributional patterns of terrestrial organisms.Ecozones delineate large areas of the Earth's surface within which organisms have been evolving in relative isolation over long periods of time, separated from...
s dividing the Earth's surface.
Physically, the Palearctic is the largest ecozone. It includes the terrestrial ecoregions of
EuropeEurope is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
,
AsiaAsia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
north of the Himalaya foothills, northern Africa, and the northern and central parts of the
Arabian PeninsulaThe Arabian Peninsula is a land mass situated north-east of Africa. Also known as Arabia or the Arabian subcontinent, it is the world's largest peninsula and covers 3,237,500 km2...
.
Major ecological regions
The Palearctic ecozone includes mostly
borealThe term boreal is usually applied to ecosystems localized in subarctic and subantarctic zones, although Austral is also used for the latter....
and
temperateIn geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...
climate ecoregions, which run across
EurasiaEurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
from western Europe to the
Bering SeaThe Bering Sea is a marginal sea of the Pacific Ocean. It comprises a deep water basin, which then rises through a narrow slope into the shallower water above the continental shelves....
.
Euro-Siberian region
The boreal and temperate Euro-Siberian region is the Palearctic's largest
biogeographicBiogeography is the study of the distribution of species , organisms, and ecosystems in space and through geological time. Organisms and biological communities vary in a highly regular fashion along geographic gradients of latitude, elevation, isolation and habitat area...
region, which transitions from
tundraIn physical geography, tundra is a biome where the tree growth is hindered by low temperatures and short growing seasons. The term tundra comes through Russian тундра from the Kildin Sami word tūndâr "uplands," "treeless mountain tract." There are three types of tundra: Arctic tundra, alpine...
in the northern reaches of
RussiaRussia or , officially known as both Russia and the Russian Federation , is a country in northern Eurasia. It is a federal semi-presidential republic, comprising 83 federal subjects...
and
ScandinaviaScandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...
to the vast
taigaTaiga , also known as the boreal forest, is a biome characterized by coniferous forests.Taiga is the world's largest terrestrial biome. In North America it covers most of inland Canada and Alaska as well as parts of the extreme northern continental United States and is known as the Northwoods...
, the boreal coniferous forests which run across the continent. South of the taiga are a belt of
temperate broadleaf and mixed forestsMixed forests are a temperate and humid biome. The typical structure of these forests includes four layers. The uppermost layer is the canopy composed of tall mature trees ranging from 33 to 66 m high. Below the canopy is the three-layered, shade-tolerant understory that is roughly 9 to...
and temperate coniferous forests. This vast Euro-Siberian region is characterized by many shared plant and animal species, and has many affinities with the temperate and boreal regions of the
NearcticThe Nearctic is one of the eight terrestrial ecozones dividing the Earth's land surface.The Nearctic ecozone covers most of North America, including Greenland and the highlands of Mexico...
ecoregion of
North AmericaNorth America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
. Eurasia and North America were often connected by the Bering land bridge, and have very similar
mammalMammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
and bird fauna, with many Eurasian species having moved into North America, and fewer North American species having moved into Eurasia. Many zoologists consider the Palearctic and Nearctic to be a single
HolarcticThe Holarctic ecozone refers to the habitats found throughout the northern continents of the world as a whole. This region is divided into the Palearctic, consisting of Northern Africa and all of Eurasia, with the exception of Southeast Asia and the Indian subcontinent, and the Nearctic,...
ecozone. The Palearctic and Nearctic also share many plant species, which botanists call the
Arcto-Tertiary GeofloraThe Arcto-Tertiary Geoflora is a hypothesized floral assemblage that once covered the Northern Hemisphere, from roughly the late Mesozoic to mid Cenozoic Eras.-Origins:First proposed by the paleobotanists J.S. Gardner and C...
.
Mediterranean Basin
The lands bordering the
Mediterranean SeaThe Mediterranean Sea is a sea connected to the Atlantic Ocean surrounded by the Mediterranean region and almost completely enclosed by land: on the north by Anatolia and Europe, on the south by North Africa, and on the east by the Levant...
in southern Europe, north Africa, and western Asia are home to the
Mediterranean basinIn biogeography, the Mediterranean Basin refers to the lands around the Mediterranean Sea that have a Mediterranean climate, with mild, rainy winters and hot, dry summers, which supports characteristic Mediterranean forests, woodlands, and scrub vegetation...
ecoregions, which together constitute world's largest and most diverse
mediterranean climateA Mediterranean climate is the climate typical of most of the lands in the Mediterranean Basin, and is a particular variety of subtropical climate...
region of the world, with generally mild, rainy winters and hot, dry summers. The Mediterranean basin's mosaic of
Mediterranean forests, woodlands, and scrubMediterranean forests, woodlands, and scrub biome, defined by the World Wildlife Fund, characterized by dry summers and rainy winters. Summers are typically hot in low-lying inland locations but can be cool near some seas, as near San Francisco, which have a sea of cool waters...
are home to 13,000
endemicEndemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
species. The Mediterranean basin is also one of the world's most endangered biogeographic regions; only 4% of the region's original vegetation remains, and human activities, including overgrazing,
deforestationDeforestation is the removal of a forest or stand of trees where the land is thereafter converted to a nonforest use. Examples of deforestation include conversion of forestland to farms, ranches, or urban use....
, and conversion of lands for pasture, agriculture, or urbanization, have degraded much of the region. Formerly the region was mostly covered with forests and woodlands, but heavy human use has reduced much of the region to the
sclerophyllSclerophyll is the term for a type of vegetation that has hard leaves and short internodes . The word comes from the Greek sclero and phyllon ....
shrublands known as
chaparralChaparral is a shrubland or heathland plant community found primarily in the U.S. state of California and in the northern portion of the Baja California peninsula, Mexico...
,
matorralMatorral is a Spanish word, along with tomillares, for shrubland, thicket or bushes. It is used in naming and describing a Mediterranean climate ecosystem in Southern Europe.-Mediterranean region:...
,
maquisthumb|220px|Low Maquis in Corsica.220px|thumb|High macchia in Sardinia.Maquis or macchia is a shrubland biome in the Mediterranean region, typically consisting of densely growing evergreen shrubs such as holm oak, tree heath, strawberry tree, sage, juniper, buckthorn, spurge olive and myrtle...
, or
garrigueGarrigue or phrygana is a type of low, soft-leaved scrubland ecoregion and plant community in the Mediterranean forests, woodlands, and scrub biome. It is found on limestone soils around the Mediterranean Basin, generally near the seacoast, where the climate is ameliorated, but where annual summer...
.
Conservation InternationalConservation International is a nonprofit organization headquartered in Arlington, Virginia, which seeks to ensure the health of humanity by protecting Earth's ecosystems and biodiversity. CI’s work focuses on six key initiatives that affect human well-being: climate, food security, freshwater...
has designated the Mediterranean basin as one of the world's
biodiversity hotspotA biodiversity hotspot is a biogeographic region with a significant reservoir of biodiversity that is under threat from humans.The concept of biodiversity hotspots was originated by Norman Myers in two articles in “The Environmentalist” , revised after thorough analysis by Myers and others in...
s.
Sahara and Arabian deserts
A great belt of desertsHorse Latitudes or Subtropical High are subtropical latitudes between 30 and 35 degrees both north and south. This region, under a ridge of high pressure called the subtropical high, is an area which receives little precipitation and has variable winds mixed with calm.The consistently warm, dry...
, including the
Atlantic coastal desertThe Atlantic coastal desert is the westernmost ecoregion in the Sahara of North Africa. It occupies a narrow strip along the Atlantic coast, where fog generated offshore by the cool Canary Current provides sufficient moisture to sustain a variety of lichens, succulents, and shrubs.It covers in...
,
SaharaThe Sahara is the world's second largest desert, after Antarctica. At over , it covers most of Northern Africa, making it almost as large as Europe or the United States. The Sahara stretches from the Red Sea, including parts of the Mediterranean coasts, to the outskirts of the Atlantic Ocean...
desert, and
Arabian desertThe Arabian Desert is a vast desert wilderness stretching from Yemen to the Persian Gulf and Oman to Jordan and Iraq. It occupies most of the Arabian Peninsula, with an area of...
, separates the Palearctic and
AfrotropicThe Afrotropic is one of the Earth's eight ecozones. It includes Africa south of the Sahara Desert, the southern and eastern fringes of the Arabian Peninsula, the island of Madagascar, southern Iran and extreme southwestern Pakistan, and the islands of the western Indian Ocean. It was formerly...
ecoregions. This scheme includes these desert ecoregions in the palearctic ecozone; other biogeographers identify the ecozone boundary as the transition zone between the desert ecoregions and the Mediterranean basin ecoregions to the north, which places the deserts in the Afrotropic, while others place the boundary through the middle of the desert.
Western and Central Asia
The
CaucasusThe Caucasus, also Caucas or Caucasia , is a geopolitical region at the border of Europe and Asia, and situated between the Black and the Caspian sea...
mountains, which run between the
Black SeaThe Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...
and the
Caspian SeaThe Caspian Sea is the largest enclosed body of water on Earth by area, variously classed as the world's largest lake or a full-fledged sea. The sea has a surface area of and a volume of...
, are a particularly rich mix of coniferous, broadleaf, and mixed forests, and include the
temperate rain forestTemperate rainforests are coniferous or broadleaf forests that occur in the temperate zone and receive high rainfall.-Definition:For temperate rain forests of North America, Alaback's definition is widely recognized:-Global distribution:...
s of the
Euxine-Colchic deciduous forestsThe Euxine-Colchic deciduous forests ecoregion, in the Temperate broadleaf and mixed forests Biome, is located along the southern shore of the Black Sea...
ecoregion.
Central AsiaCentral Asia is a core region of the Asian continent from the Caspian Sea in the west, China in the east, Afghanistan in the south, and Russia in the north...
and the
Iranian plateauThe Iranian plateau, or Iranic plateau, is a geological formation in Southwest Asia. It is the part of the Eurasian Plate wedged between the Arabian and Indian plates, situated between the Zagros mountains to the west, the Caspian Sea and the Kopet Dag to the north, the Hormuz Strait and Persian...
are home to dry
steppeIn physical geography, steppe is an ecoregion, in the montane grasslands and shrublands and temperate grasslands, savannas, and shrublands biomes, characterized by grassland plains without trees apart from those near rivers and lakes...
grasslands and
desertA desert is a landscape or region that receives an extremely low amount of precipitation, less than enough to support growth of most plants. Most deserts have an average annual precipitation of less than...
basins, with montane forests, woodlands, and grasslands in the region's high mountains and plateaux. In southern Asia the boundary of the Palearctic is largely altitudinal. The middle altitude foothills of the Himalaya between about 2000–2500 m form the boundary between the Palearctic and
IndomalayaThe Indomalaya ecozone is one of the eight ecozones that cover the planet's land surface. It extends across most of South and Southeast Asia and into the southern parts of East Asia....
ecoregions.
East Asia
ChinaChinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
,
KoreaKorea ) is an East Asian geographic region that is currently divided into two separate sovereign states — North Korea and South Korea. Located on the Korean Peninsula, Korea is bordered by the People's Republic of China to the northwest, Russia to the northeast, and is separated from Japan to the...
and
JapanJapan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
are more humid and temperate than adjacent
SiberiaSiberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
and Central Asia, and are home to rich temperate coniferous, broadleaf, and mixed forests, which are now mostly limited to mountainous areas, as the densely populated lowlands and river basins have been converted to intensive agricultural and urban use. East Asia was not much affected by glaciation in the
ice ageAn ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
s, and retained 96 percent of Pliocene tree genera, while Europe retained only 27 percent. In the subtropical southern parts of China and, the Palearctic temperate forests transition to the subtropical and tropical forests of
IndomalayaThe Indomalaya ecozone is one of the eight ecozones that cover the planet's land surface. It extends across most of South and Southeast Asia and into the southern parts of East Asia....
, creating a rich and diverse mix of plant and animal species. The
mountains of southwest ChinaThe Mountains of Southwest China is a biodiversity hotspot designated by Conservation International which includes several temperate coniferous forests in southwestern China, which lie in the river valleys on the southeastern corner of the Tibetan plateau, between the alpine scrublands and steppes...
are also designated as a
biodiversity hotspotA biodiversity hotspot is a biogeographic region with a significant reservoir of biodiversity that is under threat from humans.The concept of biodiversity hotspots was originated by Norman Myers in two articles in “The Environmentalist” , revised after thorough analysis by Myers and others in...
. In Southeastern Asia, high
mountain rangeA mountain range is a single, large mass consisting of a succession of mountains or narrowly spaced mountain ridges, with or without peaks, closely related in position, direction, formation, and age; a component part of a mountain system or of a mountain chain...
s form tongues of Palearctic flora and fauna in northern
IndochinaThe Indochinese peninsula, is a region in Southeast Asia. It lies roughly southwest of China, and east of India. The name has its origins in the French, Indochine, as a combination of the names of "China" and "India", and was adopted when French colonizers in Vietnam began expanding their territory...
and southern
ChinaChinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
. Isolated small outposts (
sky islandSky islands are mountains that are isolated by surrounding lowlands of a dramatically different environment, a situation which, in combination with the altitudinal zonation of ecosystems, has significant implications for natural habitats. Endemism, vertical migration, and relict populations are...
s) occur as far south as central Myanmar (on
Nat Ma TaungNat Ma Taung , is the highest mountain in the Chin State of western Burma. Located in Kanpalet Township, Mindat District, Mount Victoria is part of the Chin Hills range, and rises to above sea level....
, 3050 m), northernmost
VietnamVietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...
(on Fan Si Pan, 3140 m) and the high mountains of
TaiwanTaiwan , also known, especially in the past, as Formosa , is the largest island of the same-named island group of East Asia in the western Pacific Ocean and located off the southeastern coast of mainland China. The island forms over 99% of the current territory of the Republic of China following...
.
Freshwater
The ecozone contains several important freshwater ecoregions as well, including the heavily developed rivers of Europe, the rivers of Russia, which flow into the
ArcticThe Arctic is a region located at the northern-most part of the Earth. The Arctic consists of the Arctic Ocean and parts of Canada, Russia, Greenland, the United States, Norway, Sweden, Finland, and Iceland. The Arctic region consists of a vast, ice-covered ocean, surrounded by treeless permafrost...
,
BalticThe Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...
, Black, and
Caspian seaThe Caspian Sea is the largest enclosed body of water on Earth by area, variously classed as the world's largest lake or a full-fledged sea. The sea has a surface area of and a volume of...
s,
SiberiaSiberia is an extensive region constituting almost all of Northern Asia. Comprising the central and eastern portion of the Russian Federation, it was part of the Soviet Union from its beginning, as its predecessor states, the Tsardom of Russia and the Russian Empire, conquered it during the 16th...
's
Lake BaikalLake Baikal is the world's oldest at 30 million years old and deepest lake with an average depth of 744.4 metres.Located in the south of the Russian region of Siberia, between Irkutsk Oblast to the northwest and the Buryat Republic to the southeast, it is the most voluminous freshwater lake in the...
, the oldest and deepest lake on the planet, and Japan's ancient
Lake Biwais the largest freshwater lake in Japan, located in Shiga Prefecture , northeast of the former capital city of Kyoto. Because of its proximity to the ancient capital, references to Lake Biwa appear frequently in Japanese literature, particularly in poetry and in historical accounts of battles.-...
.
Flora and fauna
One bird family, the
accentorThe accentors are in the only bird family, the Prunellidae, which is completely endemic to the Palearctic. This small group of closely related passerines are all in a single genus Prunella...
s (Prunellidae) is endemic to the Palearctic region. The Holarctic has four other endemic bird families: the divers or
loonThe loons or divers are a group of aquatic birds found in many parts of North America and northern Eurasia...
s (Gaviidae),
grouseGrouse are a group of birds from the order Galliformes. They are sometimes considered a family Tetraonidae, though the American Ornithologists' Union and many others include grouse as a subfamily Tetraoninae in the family Phasianidae...
(Tetraoninae),
aukAn auk is a bird of the family Alcidae in the order Charadriiformes. Auks are superficially similar to penguins due to their black-and-white colours, their upright posture and some of their habits...
s (Alcidae), and
waxwingThe waxwings form the genus Bombycilla of passerine birds. According to most authorities, this is the only genus placed in the family Bombycillidae.-Description:Waxwings are characterised by soft silky plumage...
s (Bombycillidae).
There are no endemic
mammalMammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
orders in the region, but several families are endemic: Calomyscidae (
mouse-like hamsterthumb|200px|rightthumb|200px|right|Mouse-like hamster using its tail for balance while standing on a branch .Mouse-like hamsters are a group of small rodents found in Syria, Azerbaijan, Iran, Turkmenistan, Afghanistan, and Pakistan...
s), Prolagidae, and Ailuridae (
red pandaThe red panda , is a small arboreal mammal native to the eastern Himalayas and southwestern China. It is the only species of the genus Ailurus. Slightly larger than a domestic cat, it has reddish-brown fur, a long, shaggy tail, and a waddling gait due to its shorter front legs...
s). Several mammal species originated in the Palearctic, and spread to the Nearctic during the
ice ageAn ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
s, including the
Brown BearThe brown bear is a large bear distributed across much of northern Eurasia and North America. It can weigh from and its largest subspecies, the Kodiak Bear, rivals the polar bear as the largest member of the bear family and as the largest land-based predator.There are several recognized...
(
Ursus arctos, known in North America as the Grizzly),
Red DeerThe red deer is one of the largest deer species. Depending on taxonomy, the red deer inhabits most of Europe, the Caucasus Mountains region, Asia Minor, parts of western Asia, and central Asia. It also inhabits the Atlas Mountains region between Morocco and Tunisia in northwestern Africa, being...
(
Cervus elaphus) in Europe and the closely related
ElkThe Elk is the large deer, also called Cervus canadensis or wapiti, of North America and eastern Asia.Elk may also refer to:Other antlered mammals:...
(
Cervus canadensis) in far eastern Siberia,
American BisonThe American bison , also commonly known as the American buffalo, is a North American species of bison that once roamed the grasslands of North America in massive herds...
(
Bison bison), and
ReindeerThe reindeer , also known as the caribou in North America, is a deer from the Arctic and Subarctic, including both resident and migratory populations. While overall widespread and numerous, some of its subspecies are rare and one has already gone extinct.Reindeer vary considerably in color and size...
(
Rangifer tarandus, known in North America as the Caribou).
Palearctic terrestrial ecoregions
External links