Palearctic region

Palearctic region its fauna, boundaries, geological ranges, and climate of the region in world and variety of species present in Pakistan

1. Palearctic region its fauna, boundaries, geological ranges, and climate of
the region in world
Palearctic Region
History
In an 1858 paper for the Proceedings of the Linnean Society, British
zoologist Philip Sclater first identified six terrestrial zoogeographic realms
of the world: Palaearctic,
Aethiopian/Afrotropic, Indian/Indomalayan, Australasian, Nearctic,
and Neotropical. The six indicated general groupings of fauna, based on
shared biogeography and large-scale geographic barriers to migration.
Alfred Wallace adopted Sclater's scheme for his book The Geographical
Distribution of Animals, published in 1876. This is the same scheme that
persists today, with relatively minor revisions, and the additional of two
more realms: Oceania and the Antarctic realm.
Boundaries
The Palaearctic is one of the eight biogeographic realms on the Earth's
surface, first identified in the 19th century, and still in use today as the basis
for zoogeographic classification. The Palearctic is the largest of the eight
realms. It stretches across all of Europe, Asia north of the foothills of
the Himalayas, North Africa, and the northern and central parts of
the Arabian Peninsula.
Extreme cold of Siberia and extreme hot of Sahara desert are characteristic
climate of this region.

2. Climatic condition
Extreme cold of Siberia and extreme hot of Sahara are are characteristic
climate of this region.

Major Geological Regions
The realm consists of several ecoregions:
 the Euro-Siberian region
 the Mediterranean Basin
 the Sahara and Arabian Deserts
 Western, Central Asia
 East Asia
 Freshwater
Euro-Siberian region
The boreal and temperate Euro-Siberian region is the Palearctic's
largest biogeographic region, which transitions from tundra in the northern
reaches of Russia and Scandinavia to the vast taiga, the boreal coniferous
forests which run across the continent. South of the taiga are a belt
of temperate broadleaf and mixed forests 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 Nearctic ecoregion of North America. Eurasia and North
America were often connected by the Bering land bridge, and have very
similar mammal and bird fauna, with many Eurasian species having moved

3. into North America, and fewer North American species having moved into
Eurasia. Many zoologists consider the Palearctic and Nearctic to be a
single Holarctic realm. The Palearctic and Nearctic also share many plant
species, which botanists call the Arcto-Tertiary Geoflora.
Mediterranean Basin
The lands bordering the Mediterranean Sea in southern Europe, north Africa,
and western Asia are home to the Mediterranean Basin ecoregions, which
together constitute the world's largest and most diverse mediterranean
climate region of the world, with generally mild, rainy winters and hot, dry
summers. The Mediterranean basin's mosaic of Mediterranean forests,
woodlands, and scrub are home to 13,000 endemic 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, deforestation, 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 sclerophyll shrub lands known as chaparral, matorral, maquis,
or garrigue. Conservation International has designated the Mediterranean
basin as one of the world's biodiversity hotspots.
Sahara and Arabian deserts
A great belt of deserts, including the Atlantic coastal desert, Sahara desert,
and Arabian desert, separates the Palearctic and Afro-tropic ecoregions. This
scheme includes these desert ecoregions in the palearctic realm; other
biogeographers identify the realm boundary as the transition zone between

4. 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 Caucasus mountains, which run between the Black Sea and the Caspian
Sea, are a particularly rich mix of coniferous, broadleaf, and mixed forests,
and include the temperate rain forests of the Euxine-Colchic deciduous
forests ecoregion.
Central Asia and the Iranian plateau are home to
dry steppe grasslands and desert 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 Indomalaya ecoregions.
East Asia
China, Korea and Japan are more humid and temperate than
adjacent Siberia 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 ages, and retained 96 percent
of Pliocene tree genera, while Europe retained only 27 percent.
In the subtropical region of southern China and southern edge of the
Himalayas, the Palearctic temperate forests transition to the subtropical and
tropical forests of Indomalaya, creating a rich and diverse mix of plant and

5. animal species. The mountains of southwest China are also designated as
a biodiversity hotspot. In Southeastern Asia, high mountain ranges form
tongues of Palearctic flora and fauna in northern Indochina and
southern China. Isolated small outposts (sky islands) occur as far south as
central Myanmar (on Nat Ma Taung, 3050 m),
northernmost Vietnam (on Fan Si Pan, 3140 m) and the high mountains
of Taiwan.
Freshwater
The realm contains several important freshwater ecoregions as well,
including the heavily developed rivers of Europe, the rivers of Russia, which
flow into the Arctic, Baltic, Black, and Caspian seas, Siberia's Lake Baikal,
the oldest and deepest lake on the planet, and Japan's ancient Lake Biwa.
Fauna of Palearctic Region
This region includes Europe, Russia up to pacific coast and Mediterranean
up to Sahara. Climate is temperate and polar in the north. Eastern Asia is
temperate with deciduous forests. In northern zone there are grasslands
(steppe) and interior portion is arid.
Mammals
There are 33 families of land mammals. Animals of word-wide distribution
which amounts to one-third of families are rabbits, mice dog family, shrews,
squirrels and cat family. Animals that are restricted to the Old World include
hedge hog, porcupine, civets, giant panda (Ailuropoda), hyena and pigs.
Four families are shared with Nearctic: beavers, jumping mice, flying
squirrels, mole (Talpa) and four shared with African region. Endemic
mammals: mole rat (Spalacidae) and Camel (Seleviniidae), dormice. African

6. elements are wild horses, the prezevalski's horse is the only truly wild horse
in the world.
These are of 35 genera. Innus (tailless monkeys), Barbastellus and Plecotus
(Chiroptera): 6 genera of insectivore, Myogale, Scaptochirus, Anurosorex,
Scaptonyx, Nectogale, Uropsilus. Of carnivore, raccoon dog of Japan, otter,
badger, Panda and Seals. Camels, Deers, antelope, rodents Wolf, brown
bear, hedgehog, etc. are included.
Aves
There are 53 families of birds most of which are migratory. All birds have
wide distribution and are shared with Nearctic, Oriental and African regions,
e.g. pheasants, wrens, finches, warblers, sea birds, geese, birds of prey,
cranes, terns, gulls, grebes, hawks, ducks, quails, grouse, cuckoos, rails,
pigeons, owls, goatsuckers, kingfishers, wood peckers, larks, flycatchers,
warblers, reedlings, crows etc. Hedge sparrow is restricted to this region.

Reptiles
There is no endemic reptilian family. Lizard, Sinisaurus, and Alligartor
sinensis are endemic in China. There are lizards, snakes, Typhlops and sand
boa, Trionyx and emydine turtles, True vipers, Pit-vipers, Trigonophis,
Psammodromus, Hyalosaurus, Scincus, Ophiomorus and Megalochilus.
Amphibians
There are common newts, crested newt (Triton), Spanish newt and alpine
newt. The colourless Proteus is blind and lives in European caves. There are
European salamanders, Salamandra salamandra and S. atra and a species of

7. giant salamander (Megalobatrachus) in Japan and China that attains a length
of over 5 feet. Anurans are represented by frogs, toads, tree frogs. Male of
the midwife toad (Alytes obstetricans), which is found in France and Italy
carried eggs wrapped around his hind legs. Amphibians show affinities with
Nearctic Region.
Basically, 16 genera are present. 8 genera are of tailed amphibians- These
include Proteus, Salamandra, Hynobius, Chioglossa, Seiranota,
Onychodactylus, Geotriton. Other 8 genera of tailess amphibians are
Bombinator, Pelobates, Didocus, Alytes, Pelodytes, Discoglossus, and
Latonia
Fishes
Fish fauna also shows affinities with Nearctic. There is no endemic fish and
carp is the dominant family. There are carps, salmon, pikes, perches, eels
and Petromyzon that migrates from sea to the rivers to breed and the
ammocoete larva, commonly known as sand sleeper lives in mud for several
years in European rivers. Few species of toothless sturgeons immigrate from
sea to the rivers of Japan and Russia for laying eggs which are harvested to
prepare a delicacy called caviar. The fauna is a mixture of Old World tropics
and New World temperate.
FAUNA OF SUBREGIONS OF PALAEARCTIC
European
Northern and central Europe. Black sea. The fauna hedge hog, shrew, mole
and myogale (a mammal).
Mediterranean

8. Southern Europe. Arabian, Asia Minor, Afghanistan, Baluchistan and parts
of Russia. Fauna includes civets, hyena, hyrax.
Siberian
Northern Asia north of Himalaya having extreme climatic conditions. Fauna
includes yak, musk deer, mole, freshwater seal (Phoca sibirica) found in
Baikal lake.
Manchurian
Mongolia, Japan, Korea, Manchuria, Tibet and northern China. The fauna
contains Tibetan langur (Rhinopithecus), giant panda (Ailuropus), Chinese
water deer (Hydropotes), tufted deer (Elaphodus).
References

 http://www.notesonzoology.com/zoogeography/zoogeographical-
realms-meaning-and-types/2563
 http://www.iaszoology.com/palaearctic/
 https://www.researchgate.net/publication/229865253_Insect_Biodive
rsity_in_the_Palearctic_Region
 https://britishbirds.co.uk/article/the-boundaries-of-the-palearctic-
region/
 https://en.wikipedia.org/wiki/Palearctic_realm#/media/File:Wallace_
biogeography.jpg
 https://www.britannica.com/science/Holarctic-region#ref278177
 https://www.sciencedirect.com/science/article/pii/S100200710800145
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