116-520: The Western Ghats , also known as the Sahyadri , is a mountain range that stretches 1,600 km (990 mi) along the western coast of the Indian peninsula . Covering an area of 160,000 km (62,000 sq mi), it traverses the states of Gujarat , Maharashtra , Goa , Karnataka , Kerala , and Tamil Nadu . The range forms an almost continuous chain of mountains along the western edge of
232-509: A 2010 report, following is the distribution of faunal species in the Western Ghats apart from more than 6,000 insect species. The Western Ghats region has one of the highest tiger population, estimated at 985 in 2022. The Western Ghats ecoregion has the largest Indian elephant population in the wild, with an estimated 11,000 individuals across eight distinct populations. Other mammals include endangered and vulnerable species such as
348-405: A 2014 report, at least 227 species of reptiles are found in the Western Ghats. The major population of the snake family Uropeltidae is restricted to the region. Several endemic reptile genera and species occur here, with the region having a significant population of mugger crocodiles . The amphibians of the Western Ghats are diverse and unique, with a high proportion of species being endemic to
464-642: A complex series of orogenic events assembled the eastern parts of Gondwana (eastern Africa, Arabian-Nubian Shield, Seychelles, Madagascar, India, Sri Lanka, East Antarctica, and Australia) c. 750 to 530 Ma . First, the Arabian-Nubian Shield collided with eastern Africa (in the Kenya-Tanzania region) in the East African Orogeny c. 750 to 620 Ma . Then Australia and East Antarctica were merged with
580-599: A continuous arc chain, the direction of subduction was different between the Australian-Tasmanian and New Zealand-Antarctica arc segments. Many terranes were accreted to Eurasia during Gondwana's existence, but the Cambrian or Precambrian origin of many of these terranes remains uncertain. For example, some Palaeozoic terranes and microcontinents that now make up Central Asia, often called the "Kazakh" and "Mongolian terranes", were progressively amalgamated into
696-746: A diversified assemblage of true insects. In Gondwana, in contrast, ice and, in Australia, volcanism decimated the Devonian flora to a low-diversity seed fern flora – the pteridophytes were increasingly replaced by the gymnosperms which were to dominate until the Mid-Cretaceous. Australia, however, was still located near the Equator during the Early Carboniferous, and during this period, temnospondyl and lepospondyl amphibians and
812-472: A few million years, reached its peak at c. 200 Ma , and coincided with the Triassic–Jurassic extinction event . The reformed Gondwanan continent was not precisely the same as that which had existed before Pangaea formed; for example, most of Florida and southern Georgia and Alabama is underlain by rocks that were originally part of Gondwana, but this region stayed attached to North America when
928-594: A gradual decline during the Triassic while ferns, though never dominant, managed to diversify. The brief period of icehouse conditions during the Triassic–Jurassic extinction event had a dramatic impact on dinosaurs but left plants largely unaffected. The Jurassic was mostly one of hot-house conditions and, while vertebrates managed to diversify in this environment, plants have left little evidence of such development, apart from Cheiroleidiacean conifers and Caytoniales and other groups of seed ferns. In terms of biomass,
1044-466: A north-east motion about 90 million years ago. While subduction direction changed, it remained oblique (and not perpendicular) to the coast of South America, and the direction change affected several subduction zone -parallel faults including Atacama , Domeyko and Liquiñe-Ofqui . Insular India began to collide with Asia circa 70 Ma , forming the Indian subcontinent , since which more than 1,400 km (870 mi) of crust has been absorbed by
1160-639: A number of species related to those of the laurissilva of Valdivia, through the connection of the Antarctic flora . These include gymnosperms and the deciduous species of Nothofagus , as well as the New Zealand laurel, Corynocarpus laevigatus , and Laurelia novae-zelandiae . New Caledonia and New Zealand became separated from Australia by continental drift 85 million years ago. The islands still retain plants that originated in Gondwana and spread to
1276-544: A pattern that reflects the Jurassic break-up of Pangaea. The Cretaceous saw the arrival of the angiosperms , or flowering plants, a group that probably evolved in western Gondwana (South America–Africa). From there the angiosperms diversified in two stages: the monocots and magnoliids evolved in the Early Cretaceous, followed by the hammamelid dicots . By the Mid-Cretaceous, angiosperms constituted half of
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#17327651076171392-521: A peak in biodiversity – the end-Permian extinction was enormous and so was the radiation that followed. Two families of conifers, Podocarpaceae and Araucariaceae , dominated Gondwana in the Early Triassic, but Dicroidium , an extinct genus of fork-leaved seed ferns, dominated woodlands and forests of Gondwana during most of the Triassic. Conifers evolved and radiated during the period, with six of eight extant families already present before
1508-574: A result of long history of contact with west Asian Mediterranean traders along the Arabian sea coastline. The region includes Gujaratis in the westernmost region, Maharashtrians and Goans along the western coastline, Kannadigas in its south western coastline and Tuluvas and Malayalis in its southernmost region of South India . As a result of the thriving trade between the Mediterranean world and South West Indian coastline along
1624-853: A series of events severally restricted the Proto-ACC: change to shallow marine conditions along the North Scotia Ridge; closure of the Fuegan Seaway, the deep sea that existed in Tierra del Fuego; and uplift of the Patagonian Cordillera. This, together with the reactivated Iceland plume , contributed to global warming. During the Miocene, the Drake Passage began to widen, and as water flow between South America and
1740-694: A single jaw from Australia. The closure of the Rheic Ocean and the formation of Pangaea in the Carboniferous resulted in the rerouting of ocean currents that initiated an Ice House period. As Gondwana began to rotate clockwise, Australia shifted south to more temperate latitudes. An ice cap initially covered most of southern Africa and South America but spread to eventually cover most of the supercontinent, save for northernmost Africa-South America and eastern Australia. Giant lycopod and horsetail forests continued to evolve in tropical Laurasia together with
1856-602: A warm and humid tropical climate throughout the year. Mean temperatures range from 20 °C (68 °F) in the south to 24 °C (75 °F) in the north. Subtropical or temperate climates, and occasional near-zero temperatures during winter are experienced in regions with higher elevations. The coldest period in the region are the wettest monsoon period in the southern part of the mountain range. Annual rainfall in this region averages 100 cm (39 in) to 900 cm (350 in), with an average rainfall of 250 cm (98 in). The total amount of rain does not depend on
1972-640: Is a geo-cultural region in the Indian Subcontinent that spans the western half of Coastal India . The region was referred as Sapta Konkan region in the Skanda Purana . Coastal South West India spans across the entire Arabian Sea coastline of the Indian subcontinent from the coastline of the Gulf of Kutch in its westernmost corner and stretches across the Gulf of Khambhat , and through
2088-716: Is known as the Western Coastal Plains . The mountains can be roughly divided into three parts: the northern section with an elevation ranging from 900–1,500 m (3,000–4,900 ft), the middle section starting from the south of Goa with a lower elevation of less than 900 m (3,000 ft), and the southern section where the altitude rises again. The Western Ghats meet with the Eastern Ghats at Nilgiris before continuing south. The Western Ghats have many peaks that rise above 2,000 m (6,600 ft), with Anamudi (2,695 m (8,842 ft)) being
2204-782: Is located with respect to the Indian mainland. Ghat , a term used in the Indian subcontinent , depending on the context, could either refer to a range of stepped hills such as the Eastern Ghats and Western Ghats, or a series of steps leading down to a body of water or wharf . As per linguist Thomas Burrow , the word Ghat was derived from similar words used in various Dravidian languages such as kattu (mountain side, ridge, or dam) in Tamil , katte (dam), gatta (mountain), and gattu (bank or shore) in Kannada , and katta (dam), and gatte (shore or embankment) in Telugu . The ancient name for
2320-818: Is now the Transantarctic Mountains ): the Antarctic Peninsula , Marie Byrd Land , Zealandia , and Thurston Island ; the Falkland Islands and Ellsworth–Whitmore Mountains (in Antarctica) were rotated 90° in opposite directions; and South America south of the Gastre Fault (often referred to as Patagonia ) was pushed westward. The history of the Africa-Antarctica break-up can be studied in great detail in
2436-576: Is now the southern Weddell Sea where initial break-up occurred during the Jurassic c. 180 to 160 Ma . Gondwana began to break up in the early Jurassic following the extensive and fast emplacement of the Karoo-Ferrar flood basalts c. 184 Ma . Before the Karoo plume initiated rifting between Africa and Antarctica , it separated a series of smaller continental blocks from Gondwana's southern, Proto-Pacific margin (along what
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#17327651076172552-541: Is presumed to have been linked to the subduction of cold oceanic lithosphere . During the mid to Late Cretaceous ( c. 90 million years ago ), the Andean orogeny changed significantly in character. Warmer and younger oceanic lithosphere is believed to have started to be subducted beneath South America around this time. Such kind of subduction is held responsible not only for the intense contractional deformation that different lithologies were subject to, but also
2668-787: The Antarctic Peninsula increased, the renewed ACC resulted in cooler global climate. Since the Eocene, the northward movement of the Australian Plate has resulted in an arc-continent collision with the Philippine and Caroline plates and the uplift of the New Guinea Highlands . From the Oligocene to the late Miocene, the climate in Australia, dominated by warm and humid rainforests before this collision, began to alternate between open forest and rainforest before
2784-574: The Arabian Sea . The Western Ghats play an important role in determining the climate and seasons in India. It blocks the rain-bearing monsoon winds flowing eastward from the Arabian Sea, resulting in rainfall along the western coast. By the time the air rises above the mountains, it becomes dry, forming a rain shadow region with very little rainfall on the leeward side towards the interior of
2900-1075: The Australian Plate are now separated by the Capricorn Plate and its diffuse boundaries. During the opening of the Indian Ocean, the Kerguelen hotspot first formed the Kerguelen Plateau on the Antarctic Plate c. 118 to 95 Ma and then the Ninety East Ridge on the Indian Plate at c. 100 Ma . The Kerguelen Plateau and the Broken Ridge , the southern end of the Ninety East Ridge, are now separated by
3016-650: The Cambrian explosion occurred. Laurentia was docked against the western shores of a united Gondwana for a brief period near the Precambrian/Cambrian boundary, forming the short-lived and still disputed supercontinent Pannotia . The Mozambique Ocean separated the Congo – Tanzania – Bangweulu Block of central Africa from Neoproterozoic India (India, the Antongil Block in far eastern Madagascar,
3132-844: The Campbell Plateau , Chatham Rise , Lord Howe Rise , Norfolk Ridge , and New Caledonia , from West Antarctica c. 84 Ma . The opening of the South Atlantic Ocean divided West Gondwana (South America and Africa), but there is considerable debate over the exact timing of this break-up. Rifting propagated from south to north along Triassic–Early Jurassic lineaments, but intra-continental rifts also began to develop within both continents in Jurassic–Cretaceous sedimentary basins, subdividing each continent into three sub-plates. Rifting began c. 190 Ma at Falkland latitudes, forcing Patagonia to move relative to
3248-602: The Central Atlantic opened . Antarctica, the centre of the supercontinent, shared boundaries with all other Gondwana continents and the fragmentation of Gondwana propagated clockwise around it. The break-up was the result of the eruption of the Karoo-Ferrar igneous province , one of the Earth's most extensive large igneous provinces (LIP) c. 200 to 170 Ma , but the oldest magnetic anomalies between South America, Africa, and Antarctica are found in what
3364-621: The Cyprinids (72 species), hillstream loaches (34 species; including stone loaches , now regarded a separate family), Bagrid catfishes (19 species), and Sisorid catfishes (12 species). The region is home to several ornamental fishes like the Denison (or red line torpedo) barb , melon barb , several species of Dawkinsia barbs, zebra loach , Horabagrus catfish, dwarf pufferfish and dwarf Malabar pufferfish . The rivers are also home to Osteobrama bakeri , and larger species such as
3480-580: The Deccan Plateau , from the Tapti River to Swamithoppe in Kanyakumari district at the southern tip of the Indian peninsula. The Western Ghats meet with the Eastern Ghats at Nilgiris before continuing south. Geologic evidence indicates that the mountains were formed during the break-up of the supercontinent of Gondwana . The mountains came along the west coast of India somewhere in
3596-834: The Drake Passage and the deepening of the Tasman Gateway. The oldest oceanic crust in the Drake Passage, however, is 34 to 29 Ma -old which indicates that the spreading between the Antarctic and South American plates began near the Eocene/Oligocene boundary. Deep sea environments in Tierra del Fuego and the North Scotia Ridge during the Eocene and Oligocene indicate a "Proto-ACC" opened during this period. Later, 26 to 14 Ma ,
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3712-757: The Great American Interchange . The break-up of Gondwana can be said to continue in eastern Africa at the Afar Triple Junction , which separates the Arabian , Nubian , and Somali plates, resulting in rifting in the Red Sea and East African Rift . In the Early Cenozoic , Australia was still connected to Antarctica c. 35–40° south of its current location and both continents were largely unglaciated. A rift between
3828-803: The Himalayan - Tibetan orogen. During the Cenozoic, the orogen resulted in the construction of the Tibetan Plateau between the Tethyan Himalayas in the south and the Kunlun and Qilian mountains in the north. Later, South America was connected to North America via the Isthmus of Panama , cutting off a circulation of warm water and thereby making the Arctic colder, as well as allowing
3944-457: The Jonakan Mappilas along Malabar region, and the cochin jews and Syriac Nasranis along the southernmost region of South India . The linguistic diversity of the Coastal south west India includes Languages of the Dravidian language family including Malayalam , Tulu , and Kannada ; languages belonging to the western zone of Indo Iranian language families including Gujarati , Marathi , Konkani and languages belonging to
4060-607: The Malabar snakehead , and Malabar mahseer . A few are adapted to an underground life, including some Rakthamichthys swamp eels, and the catfish Horaglanis and Kryptoglanis . 97 freshwater fish species were considered threatened in 2011, including 12 critically endangered, 54 endangered, and 31 vulnerable. The reservoirs in the region are important for their commercial and sport fisheries of rainbow trout , mahseer , and common carp . There are more than 200 freshwater fish species including 35 also known from brackish or marine water. Several new species have been described from
4176-414: The Malagasy Orogeny in southern Madagascar) ( 550 Ma ), the collision between East Gondwana and East Africa in two steps, and the Brasiliano orogeny ( 660 to 530 Ma ), the successive collision between South American and African cratons . The last stages of Gondwanan assembly overlapped with the opening of the Iapetus Ocean between Laurentia and western Gondwana. During this interval,
4292-422: The Mozambique Belt , formed 800 to 650 Ma and was originally interpreted as the suture between East (India, Madagascar, Antarctica, and Australia) and West Gondwana (Africa and South America). Three orogenies were recognised during the 1990s as a result of data sets compiled on behalf of oil and mining companies: the East African Orogeny ( 650 to 800 Ma ) and Kuunga orogeny (including
4408-481: The Ordovician . This is the Cuyania or Precordillera terrane of the Famatinian orogeny in northwest Argentina which may have continued the line of the Appalachians southwards. Chilenia terrane accreted later against Cuyania. The collision of the Patagonian terrane with the southwestern Gondwanan occurred in the late Paleozoic. Subduction-related igneous rocks from beneath the North Patagonian Massif have been dated at 320–330 million years old, indicating that
4524-481: The Pangaea supercontinent during the Carboniferous. Pangaea began to break up in the Mid-Jurassic when the Central Atlantic opened . In the western end of Pangaea, the collision between Gondwana and Laurasia closed the Rheic and Palaeo-Tethys oceans. The obliquity of this closure resulted in the docking of some northern terranes in the Marathon , Ouachita , Alleghanian , and Variscan orogenies, respectively. Southern terranes, such as Chortis and Oaxaca , on
4640-437: The Salsette Island and Mumbai along the Konkan and southwards across the Raigad region and through Kanara and further down through Mangaluru ( Mangalore ) and along the Malabar unto the southernmost tip to Kanyakumari (Cape Comorin). In ancient tradition Coastal South West Indian Subcontinent extends till Sri Lanka . The people along coastal south west India exhibit vast diversity along an underlying commonality as
4756-483: The Seychelles , and the Napier and Rayner Complexes in East Antarctica ). The Azania continent (much of central Madagascar , the Horn of Africa and parts of Yemen and Arabia) was an island in the Mozambique Ocean. The continent Australia/ Mawson was still separated from India, eastern Africa, and Kalahari by c. 600 Ma , when most of western Gondwana had already been amalgamated. By c. 550 Ma, India had reached its Gondwanan position, which initiated
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4872-499: The Southeast Indian Ridge . Separation between Australia and East Antarctica began c. 132 Ma with seafloor spreading occurring c. 96 Ma . A shallow seaway developed over the South Tasman Rise during the Early Cenozoic and as oceanic crust started to separate the continents during the Eocene c. 35.5 Ma global ocean temperature dropped significantly. A dramatic shift from arc- to rift magmatism c. 100 Ma separated Zealandia , including New Zealand ,
4988-404: The Triassic , and started to fragment during the Early Jurassic (around 180 million years ago). The final stages of break-up, involving the separation of Antarctica from South America (forming the Drake Passage ) and Australia, occurred during the Paleogene (from around 66 to 23 million years ago (Ma)). Gondwana was not considered a supercontinent by the earliest definition, since
5104-442: The Uralian orogeny and Laurasia . Pangaea was finally amalgamated in the Late Carboniferous-Early Permian, but the oblique forces continued until Pangaea began to rift in the Triassic. In the eastern end, collisions occurred slightly later. The North China , South China , and Indochina blocks rifted from Gondwana during the middle Paleozoic and opened the Proto-Tethys Ocean . North China docked with Mongolia and Siberia during
5220-422: The Variscan orogeny close to the Carboniferous–Permian boundary. South-east Asia was made of Gondwanan and Cathaysian continental fragments that were assembled during the Mid-Palaeozoic and Cenozoic. This process can be divided into three phases of rifting along Gondwana's northern margin: first, in the Devonian, North and South China , together with Tarim and Quidam (north-western China) rifted, opening
5336-446: The crimson-backed sunbird . There is a higher fish species richness in the southern part of the Western Ghats. There are 13 genera entirely restricted to the Western Ghats ( Betadevario , Dayella , Haludaria , Horabagrus , Horalabiosa , Hypselobarbus , Indoreonectes , Lepidopygopsis , Longischistura , Mesonoemacheilus , Parapsilorhynchus , Rohtee , and Travancoria ). The most species-rich families are
5452-554: The late Jurassic and early Cretaceous periods when India separated from the African continent. The mountains can be roughly divided into three parts: the northern section with an elevation ranging from 900–1,500 m (3,000–4,900 ft), the middle section starting from the south of Goa with a lower elevation of less than 900 m (3,000 ft), and the southern section where the altitude rises again. The Western Ghats have several peaks that rise above 2,000 m (6,600 ft), with Anamudi (2,695 m (8,842 ft)) being
5568-414: The leeward side towards the interior of the Deccan plateau. The monsoon winds rounding up the peninsula and moving from the east from the Bay of Bengal pass over the Eastern Ghats and bring the majority of the rainfall to the plains up north. Climate in the mountains shows variations with altitude across the range. Due to its physical proximity to the equator and the Arabian Sea, the region experiences
5684-424: The lion-tailed macaque , Nilgiri tahr , leopard , Nilgiri langur , dhole , and gaur . The endemic Nilgiri tahr, which was on the brink of extinction, has recovered and had an estimated 3,122 individuals in 2015. Smaller endemic species include the Malabar large-spotted civet , Nilgiri marten , brown palm civet , stripe-necked mongoose , Indian brown mongoose , small Indian civet , and leopard cat . As per
5800-403: The region in central India of the same name , which is derived from Sanskrit for "forest of the Gonds ". The name had been previously used in a geological context, first by H. B. Medlicott in 1872, from which the Gondwana sedimentary sequences ( Permian - Triassic ) are also described. Some scientists prefer the term "Gondwanaland" for the supercontinent to make a clear distinction between
5916-444: The tropical rainforests of India . New frog species have continued to be discovered in the 21st century. Frogs of the genera Micrixalus , Indirana , and Nyctibatrachus , toads like Pedostibes , Ghatophryne , and Xanthophryne , arboreal frogs like Ghatixalus , Mercurana , and Beddomixalus , and microhylids like Melanobatrachus are endemic to this region. There are at least 19 species of birds endemic to
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#17327651076176032-403: The uplift and erosion known to have occurred from the Late Cretaceous onward. Plate tectonic reorganisation since the mid-Cretaceous might also have been linked to the opening of the South Atlantic Ocean . Another change related to mid-Cretaceous plate tectonic rearrangement was the change of subduction direction of the oceanic lithosphere that went from having south-east motion to having
6148-422: The 334 Western Ghats butterfly species, 316 species have been reported to occur in the Nilgiri Biosphere Reserve . The Western Ghats are home to 174 species of odonates (107 dragonflies and 67 damselflies ), including 69 endemics. Most of the endemic odonate are closely associated with rivers and streams, while the non-endemics are typically generalists . There are several species of leeches found all along
6264-457: The Arabian sea, there has been significant intermingling between the people of Coastal South West India and the west asian world. Several west Asian communities have also settled and become part of the diversity of coastal south west India. These include the Parsis , Bohras and Baghdadi Jews in the westernmost region, the Bene Israel along the South western region the descendants of mediterranean traders along Coorg and Mangalore ,
6380-502: The Carboniferous–Permian, followed by South China. The Cimmerian blocks then rifted from Gondwana to form the Palaeo-Thethys and Neo-Tethys oceans in the Late Carboniferous, and docked with Asia during the Triassic and Jurassic. Western Pangaea began to rift while the eastern end was still being assembled. The formation of Pangaea and its mountains had a tremendous impact on global climate and sea levels, which resulted in glaciations and continent-wide sedimentation. In North America,
6496-418: The Deccan plateau. The Western Ghats region is a biodiversity hotspot . It contains a large number of different species of flora and fauna, most of which are endemic to this region. At least 325 globally threatened species occur in the Western Ghats. The region was declared as a UNESCO World Heritage Site in 2012. The name Western Ghats derives from the word ghat and the cardinal direction in which it
6612-405: The Early Cretaceous, and West Burma and Woyla during the Late Cretaceous. Gondwana's long, northern margin remained a mostly passive margin throughout the Palaeozoic. The Early Permian opening of the Neo-Tethys Ocean along this margin produced a long series of terranes, many of which were and still are being deformed in the Himalaya Orogeny . These terranes are, from Turkey to north-eastern India:
6728-448: The Equator during this period and remained a lifeless and barren landscape. West Gondwana drifted north during the Devonian , bringing Gondwana and Laurasia close together. Global cooling contributed to the Late Devonian extinction (19% of marine families and 50% of genera went extinct) and glaciation occurred in South America. Before Pangaea had formed, terrestrial plants, such as pteridophytes , began to diversify rapidly resulting in
6844-400: The Equator on landmasses then limited to Laurasia and, in Gondwana, to Australia. In the late Silurian, two distinctive lineages, zosterophylls and rhyniophytes , had colonised the tropics. The former evolved into the lycopods that were to dominate the Gondwanan vegetation over a long period, whilst the latter evolved into horsetails and gymnosperms . Most of Gondwana was located far from
6960-421: The Gujarati People and Thiruvathira festival among the Malayali people. Gondwana Gondwana ( / ɡ ɒ n d ˈ w ɑː n ə / ) was a large landmass, sometimes referred to as a supercontinent . The remnants of Gondwana make up around two-thirds of today's continental area, including South America , Africa , Antarctica , Australia , Zealandia , Arabia , and the Indian Subcontinent . Gondwana
7076-446: The Jurassic flora was dominated by conifer families and other gymnosperms that had evolved during the Triassic. The Pteridophytes that had dominated during the Palaeozoic were now marginalised, except for ferns. In contrast to Laurentia, very few insect fossils have been found in Gondwana, to a considerable extent because of widespread deserts and volcanism. While plants had a cosmopolitan distribution, dinosaurs evolved and diversified in
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#17327651076177192-406: The Kuunga orogeny (also known as the Pinjarra orogeny). Meanwhile, on the other side of the newly forming Africa, Kalahari collided with Congo and Rio de la Plata which closed the Adamastor Ocean . c. 540–530 Ma, the closure of the Mozambique Ocean brought India next to Australia–East Antarctica, and both North and South China were in proximity to Australia. As the rest of Gondwana formed,
7308-422: The Late Permian, many known from South Africa and Australia. Beetles and cockroaches remained minor elements in this fauna. Tetrapod fossils from the Early Permian have only been found in Laurasia but they became common in Gondwana later during the Permian. The arrival of the therapsids resulted in the first plant-vertebrate-insect ecosystem. During the Mid- to Late Triassic, hot-house conditions coincided with
7424-405: The Miocene, a warm and humid climate developed with pockets of rainforests in central Australia, but before the end of the period, colder and drier climate severely reduced this rainforest. A brief period of increased rainfall in the Pliocene was followed by drier climate which favoured grassland. Since then, the fluctuation between wet interglacial periods and dry glacial periods has developed into
7540-443: The Neoproterozoic to Palaeozoic phase of the Terra Australis Orogen , a series of terranes were rafted from the proto-Andean margin when the Iapteus Ocean opened, to be added back to Gondwana during the closure of that ocean. During the Paleozoic, some blocks which helped to form parts of the Southern Cone of South America, include a piece transferred from Laurentia when the west edge of Gondwana scraped against southeast Laurentia in
7656-441: The Palaeo-Tethys behind them. These terranes accreted to Asia during Late Devonian and Permian. Second, in the Late Carboniferous to Early Permian, Cimmerian terranes opened Meso-Tethys Ocean; Sibumasu and Qiangtang were added to south-east Asia during Late Permian and Early Jurassic. Third, in the Late Triassic to Late Jurassic, Lhasa , West Burma , Woyla terranes opened the Neo-Tethys Ocean; Lhasa collided with Asia during
7772-456: The South Atlantic (Brazil and Cameroon ) dating to around 120 million years ago , suggesting that some form of land connection still existed between Africa and South America as recently as the early Aptian . The first phases of Andean orogeny in the Jurassic and Early Cretaceous were characterised by extensional tectonics , rifting , the development of back-arc basins and the emplacement of large batholiths . This development
7888-465: The Southern Hemisphere, has a "Gondwanan distribution" and is often described as an archaic, or relict , lineage. The distributions in the Proteaceae is, nevertheless, the result of both Gondwanan rafting and later oceanic dispersal. During the Silurian, Gondwana extended from the Equator (Australia) to the South Pole (North Africa and South America) whilst Laurasia was located on the Equator opposite to Australia. A short-lived Late Ordovician glaciation
8004-408: The Taurides in southern Turkey; the Lesser Caucasus Terrane in Georgia; the Sanand, Alborz, and Lut terranes in Iran; the Mangysglak or Kopetdag Terrane in the Caspian Sea; the Afghan Terrane; the Karakorum Terrane in northern Pakistan; and the Lhasa and Qiangtang terranes in Tibet. The Permian–Triassic widening of the Neo-Tethys pushed all these terranes across the Equator and over to Eurasia. During
8120-510: The Western Ghats including the endangered rufous-breasted laughingthrush , the vulnerable Nilgiri wood-pigeon , white-bellied shortwing , and broad-tailed grassbird , the near threatened grey-breasted laughingthrush , black-and-rufous flycatcher , Nilgiri flycatcher , and Nilgiri pipit , and the least concern Malabar (blue-winged) parakeet , Malabar grey hornbill , white-bellied treepie , grey-headed bulbul , rufous babbler , Wayanad laughingthrush , white-bellied blue-flycatcher , and
8236-845: The Western Ghats were severely fragmented due to clear-felling for plantations. The introduction of non-native species threatened the rare endemic species and habitat specialists, which depleted faster than other species. Complex and species-rich habitats like the tropical rainforests are much more adversely affected than other habitats. The primary threats to fauna were not only from habitat loss , but also from overexploitation , illicit grazing , mining , poaching , and introduced species . The Government of India has established many protected areas , including two biosphere reserves , 13 national parks to restrict human access, several wildlife sanctuaries to protect specific endangered species, and many reserve forests . The Nilgiri Biosphere Reserve , comprising 5,500 km (2,100 sq mi) of
8352-559: The Western Ghats, but the actual number is likely higher. This includes 28 endemics. Among the threatened freshwater molluscs are the mussel species Pseudomulleria dalyi , which is a Gondwanan relict, and the snail Cremnoconchus , which is restricted to the spray zone of waterfalls. According to the IUCN, four species of freshwater molluscs are considered endangered and three are vulnerable. An additional 19 species are considered data deficient. There are roughly 6,000 insect species. Of
8468-442: The Western Ghats. Historically, the Western Ghats were covered in dense forests. which formed the natural habitat for wildlife along with the native tribal people . Its inaccessibility made it difficult for people from the plains to cultivate the land and build settlements. After the establishment of British colonial rule in the region, large swathes of territory were cleared for agricultural plantations and timber. The forests in
8584-539: The Western Ghats. The Western Ghats consist of four tropical and subtropical moist broadleaf terrestrial ecoregions of the Indomalayan realm , with the northern portion of the range generally drier than the southern portion. These include the following: Other types of ecosystems include dry deciduous forests on the leeward rain shadow region, scrub forests at the foothills, peat bogs , and swamps . Montane grasslands are found in high altitude locations in
8700-526: The addition of Australia and Antarctica, respectively. Eventually, Gondwana became the largest piece of continental crust of the Palaeozoic Era, covering an area of some 100,000,000 km (39,000,000 sq mi), about one-fifth of the Earth's surface. It fused with Euramerica during the Carboniferous to form Pangea . It began to separate from northern Pangea ( Laurasia ) during
8816-779: The base of the Absaroka sequence coincides with the Alleghanian and Ouachita orogenies and are indicative of a large-scale change in the mode of deposition far away from the Pangaean orogenies. Ultimately, these changes contributed to the Permian–Triassic extinction event and left large deposits of hydrocarbons, coal, evaporite, and metals. The breakup of Pangaea began with the Central Atlantic magmatic province (CAMP) between South America, Africa, North America, and Europe. CAMP covered more than seven million square kilometres over
8932-501: The central zone of the Indo-Iranian language families including Urdu and Persian . The region also has speakers of Semitic languages like Arabic , Hebrew and Aramaic . The common elements of the people of coastal south west India includes cuisine that consists of agrarian and coastal products and clothing that involves long flowing drapes with bare midriff for both men and women suited for humid and warm climate. Throughout
9048-540: The colonisation of Gondwana. The Baragwanathia Flora, found only in the Yea Beds of Victoria, Australia, occurs in two strata separated by 1,700 m (5,600 ft) or 30 Ma; the upper assemblage is more diverse and includes Baragwanathia, the first primitive herbaceous lycopod to evolve from the zosterophylls. During the Devonian, giant club mosses replaced the Baragwanathia Flora, introducing
9164-753: The continent Kazakhstania in the late Silurian . Whether these blocks originated on the shores of Gondwana is not known. In the Early Palaeozoic, the Armorican terrane , which today form large parts of France, was part of either Peri-Gondwana or core Gondwana; the Rheic Ocean closed in front of it and the Palaeo-Tethys Ocean opened behind it. Precambrian rocks from the Iberian Peninsula suggest that it, too, formed part of core Gondwana before its detachment as an orocline in
9280-424: The continent became the arid or semiarid landscape it is today. The adjective "Gondwanan" is in common use in biogeography when referring to patterns of distribution of living organisms, typically when the organisms are restricted to two or more of the now-discontinuous regions that were once part of Gondwana, including the Antarctic flora . For example, the plant family Proteaceae , known from all continents in
9396-833: The development of rifts systems on both continents, including the Central African Rift System and the Central African Shear Zone which lasted until c. 85 Ma . At Brazilian latitudes spreading is more difficult to assess because of the lack of palaeo-magnetic data, but rifting occurred in Nigeria at the Benue Trough c. 118 Ma . North of the Equator the rifting began after 120.4 Ma and continued until c. 100 to 96 Ma . Dinosaur footprints representing identical species assemblages are known from opposite sides of
9512-556: The end of it. Bennettitales and Pentoxylales , two now extinct orders of gymnospermous plants, evolved in the Late Triassic and became important in the Jurassic and Cretaceous. It is possible that gymnosperm biodiversity surpassed later angiosperm biodiversity and that the evolution of angiosperms began during the Triassic but, if so, in Laurasia rather than in Gondwana. Two Gondwanan classes, lycophytes and sphenophytes , saw
9628-996: The eruption of the Deccan basalts , whose eruption site may survive as the Réunion hotspot . The Seychelles and the Maldives are now separated by the Central Indian Ridge . During the initial break-up in the Early Jurassic a marine transgression swept over the Horn of Africa covering Triassic planation surfaces with sandstone , limestone , shale , marls and evaporites . East Gondwana, comprising Antarctica, Madagascar, India, and Australia, began to separate from Africa. East Gondwana then began to break up c. 132.5 to 96 Ma when India moved northwest from Australia-Antarctica. The Indian Plate and
9744-563: The evolution of Voltziales , one of the few plant orders to survive the end-Permian extinction (57% of marine families and 83% of genera went extinct) and which came to dominate in the Late Permian and from whom true conifers evolved. Tall lycopods and horsetails dominated the wetlands of Gondwana in the Early Permian. Insects co-evolved with glossopterids across Gondwana and diversified with more than 200 species in 21 orders by
9860-564: The first amniote reptilians evolved, all closely related to the Laurasian fauna, but spreading ice eventually drove these animals away from Gondwana entirely. The Gondwana ice sheet melted, and sea levels dropped during the Permian and Triassic global warming. During this period, the extinct glossopterids colonised Gondwana and reached peak diversity in the Late Permian when coal-forming forests covered much of Gondwana. The period also saw
9976-522: The first trees, and by the Late Devonian this first forest was accompanied by the progymnosperms , including the first large trees Archaeopteris . The Late Devonian extinction probably also resulted in osteolepiform fishes evolving into the amphibian tetrapods , the earliest land vertebrates, in Greenland and Russia. The only traces of this evolution in Gondwana are amphibian footprints and
10092-526: The flora in northeastern Australia. There is, however, no obvious connection between this spectacular angiosperm radiation and any known extinction event nor with vertebrate/insect evolution. Insect orders associated with pollination, such as beetles , flies , butterflies and moths , and wasps, bees, and ants , radiated continuously from the Permian-Triassic, long before the arrival of the angiosperms. Well-preserved insect fossils have been found in
10208-656: The forests, forms the largest contiguous protected area in the Western Ghats. In August 2011, the Western Ghats Ecology Expert Panel (WGEEP), appointed by the Union Ministry of Environment and Forests to assess the biodiversity and environmental issues of the Western Ghats, designated the entire region as an Ecologically Sensitive Area (ESA) and assigned three levels of Ecological Sensitivity to its different regions. Subsequent committees formed have recommended various suggestions to protect
10324-694: The fracture zones and magnetic anomalies flanking the Southwest Indian Ridge . The Madagascar block and the Mascarene Plateau , stretching from the Seychelles to Réunion , were broken off India, causing Madagascar and Insular India to be separate landmasses : elements of this break-up nearly coincide with the Cretaceous–Paleogene extinction event . The India–Madagascar–Seychelles separations appear to coincide with
10440-536: The highest peak. The Western Ghats form one of the major watersheds of India, feeding many perennial rivers. These major river systems drain almost 40% of the land area of the country. The major river systems originating in the Western Ghats are the Godavari , Kaveri , and Krishna . Most rivers flow eastwards towards the Bay of Bengal owing to the steeper gradient moving from east to west, and many smaller streams drain
10556-489: The highest peak. The average elevation is around 1,200 m (3,900 ft). The Western Ghats form one of the major watersheds of India, feeding many perennial river systems that drain almost 40% of the land area of the country. Because of the higher elevation of the Deccan plateau on the west, most rivers flow from eastwards towards the Bay of Bengal , resulting in chiselled eastern slopes and steeper western slopes facing
10672-553: The indigenous species, 2,253 species are endemic to India and of them, 1,273 species are exclusively confined to the Western Ghats. 645 tree species were recorded with a high endemic ratio of 56%. There are 850 – 1000 species of bryophytes including 682 species of mosses (28% endemic) and 280 species of liverworts (43% endemic), 277 species of pteridophytes and 949 species of lichens (26.7% endemic). The Western Ghats are home to thousands of species of fauna, including at least 325 globally threatened species . As per
10788-861: The lake deposits of the Santana Formation in Brazil, the Koonwarra Lake fauna in Australia, and the Orapa diamond mine in Botswana. Dinosaurs continued to prosper but, as the angiosperm diversified, conifers, bennettitaleans and pentoxylaleans disappeared from Gondwana c. 115 Ma together with the specialised herbivorous ornithischians , whilst generalist browsers, such as several families of sauropodomorph Saurischia , prevailed. The Cretaceous–Paleogene extinction event killed off all dinosaurs except birds, but plant evolution in Gondwana
10904-487: The land, which draws air from the sea. The air, which picks up moisture along the way and flows eastward from the Arabian Sea, is blocked by the Western Ghats. The rising air cools and brings about orographic precipitation along the western coast. This signifies the onset of the monsoon season in June. By the time the air rises above the mountains, it becomes dry, resulting in a rain shadow region with very little rainfall on
11020-459: The landmasses of Baltica , Laurentia , and Siberia were separated from it. To differentiate it from the Indian region of the same name (see § Name ), it is also commonly called Gondwanaland . Regions that were part of Gondwana shared floral and zoological elements that persist to the present day. The continent of Gondwana was named by the Austrian scientist Eduard Suess , after
11136-465: The mountain range is Sahyadri , derived from Sanskrit , meaning benevolent or tolerant mountain. The Western Ghats are the mountainous faulted , and eroded edge of the Deccan Plateau . Geologic evidence indicates that they were formed during the break-up of the super-continent of Gondwana . After the break-up, the Deccan plateau was formed by basalt rocks, which caused the western side to rise at an elevation. Geophysical evidence indicates that
11252-491: The mountains came along the west coast of India somewhere in the late Jurassic and early Cretaceous periods when India separated from the African continent. Several faults triggered the formation of Western Ghats, then interspersed with valleys and river gorges. Because of the elevation of the Deccan plateau on the west, most rivers flow from west to east, resulting in chiselled eastern slopes and steeper western slopes facing
11368-600: The other hand, remained largely unaffected by the collision along the southern shores of Laurentia. Some Peri-Gondwanan terranes, such as Yucatán and Florida , were buffered from collisions by major promontories. Other terranes, such as Carolina and Meguma , were directly involved in the collision. The final collision resulted in the Variscan- Appalachian Mountains , stretching from present-day Mexico to southern Europe. Meanwhile, Baltica collided with Siberia and Kazakhstania which resulted in
11484-561: The present arid regime. Australia has thus experienced various climate changes over a 15-million-year period with a gradual decrease in precipitation. The Tasman Gateway between Australia and Antarctica began to open c. 40 to 30 Ma . Palaeontological evidence indicates the Antarctic Circumpolar Current (ACC) was established in the Late Oligocene c. 23 Ma with the full opening of
11600-526: The region and the supercontinent. The assembly of Gondwana was a protracted process during the Neoproterozoic and Paleozoic , which remains incompletely understood because of the lack of paleo-magnetic data. Several orogenies , collectively known as the Pan-African orogeny , caused the continental fragments of a much older supercontinent, Rodinia , to amalgamate. One of those orogenic belts,
11716-425: The region since the last decade (e.g., Dario urops and S. sharavathiensis ). Seasonal rainfall patterns in the Western Ghats necessitate a period of dormancy for its land snails , resulting in their high abundance and diversity, including at least 258 species of gastropods from 57 genera and 24 families. A total of 77 species of freshwater molluscs (52 gastropods and 25 bivalves ) have been recorded from
11832-401: The region women wear drapes called saree in various styles. In the western corner of the region the drapes are called as Dhoti for men. and Chaniya choli for women, further southwards the drapes are called as lungi or mundu for men. and veshti for women. Another common cultural element of coastal south west India includes relatively more role for women in social system. Towards
11948-441: The region, often carrying a large volume of water during the monsoon months. The streams and rivers give rise to numerous waterfalls in the region. The rivers have been dammed for hydroelectric and irrigation purposes, with major reservoirs spread across the region. The Western Ghats play an important role in determining the climate and seasons in India. During the dry summer months of April – May, heat builds up on
12064-534: The region. In 2006, India applied to the UNESCO Man and the Biosphere Programme (MAB) for the Western Ghats to be listed as a protected World Heritage Site . In 2012, 39 sites divided into seven clusters across the Western Ghats, were declared as World Heritage Sites. [REDACTED] Media related to Western Ghats at Wikimedia Commons West Coast of India Coastal South West India
12180-760: The remaining Gondwana c. 570 to 530 Ma in the Kuunga Orogeny. The later Malagasy orogeny at about 550–515 Mya affected Madagascar, eastern East Africa and southern India. In it, Neoproterozoic India collided with the already combined Azania and Congo–Tanzania–Bangweulu Block, suturing along the Mozambique Belt. The 18,000 km-long (11,000 mi) Terra Australis Orogen developed along Gondwana's western, southern, and eastern margins. Proto-Gondwanan Cambrian arc belts from this margin have been found in eastern Australia, Tasmania, New Zealand, and Antarctica. Though these belts formed
12296-675: The sea. The Western Ghats extend from the Satpura Range south of the Tapti River in the north and runs approximately 1,600 km (990 mi) to the southern tip of the Indian peninsula, where it ends at the Marunthuvazh Malai at Swamithoppe in Kanyakumari district . It covers an area of 160,000 km (62,000 sq mi), traversing across the Indian states of Gujarat , Maharashtra , Goa , Karnataka , Kerala , and Tamil Nadu . The Western Ghats form an almost continuous chain of mountains running parallel to
12412-513: The south Western Ghats interspersed with sholas , a unique type of stunted tropical montane forest found in the valleys between the mountains. Earlier sources indicated about four to five thousand vascular plant species of which nearly one-third was endemic to the region. Later studies and publications have recorded 7,402 species of flowering plants occurring in the Western Ghats of which 5,588 were described as indigenous, 376 are naturalized exotics, and 1,438 species are cultivated or planted. Among
12528-546: The southernmost tip of coastal south western India the social system is considerably more matri-focal with instances of matrilineal and matriarchal tradition like amongst the Bunt community of Tulus and the Marumakkathayam of the nairs and a section of Mappila Muslims . This is also manifested in feminine deity oriented festivals and rituals celebrating Shakti or feminine power like Navratri festival among
12644-456: The spread of the area; areas in northern Maharashtra receive heavy rainfall followed by long dry spells, while regions closer to the equator receive lower annual rainfall and have rain spells lasting several months in a year. The Western Ghats region is a biodiversity hotspot . It consists of nearly 30% of all the species of flora and fauna found in India, most of which are endemic to this region. At least 325 globally threatened species occur in
12760-665: The still static remainder of South America and Africa, and this westward movement lasted until the Early Cretaceous 126.7 Ma . From there rifting propagated northward during the Late Jurassic c. 150 Ma or Early Cretaceous c. 140 Ma most likely forcing dextral movements between sub-plates on either side. South of the Walvis Ridge and Rio Grande Rise the Paraná and Etendeka magmatics resulted in further ocean-floor spreading c. 130 to 135 Ma and
12876-399: The subduction process initiated in the early Carboniferous. This was relatively short-lived (lasting about 20 million years), and initial contact of the two landmasses occurred in the mid-Carboniferous, with broader collision during the early Permian. In the Devonian, an island arc named Chaitenia accreted to Patagonia in what is now south-central Chile. Gondwana and Laurasia formed
12992-636: The two developed but remained an embayment until the Eocene-Oligocene boundary when the Circumpolar Current developed and the glaciation of Antarctica began. Australia was warm and wet during the Palaeocene and dominated by rainforest. The opening of the Tasman Gateway at the Eocene-Oligocene boundary ( 33 Ma ) resulted in abrupt cooling but the Oligocene became a period of high rainfall with swamps in southeast Australia. During
13108-412: The western coast of India along the Arabian Sea . The average elevation is around 1,200 m (3,900 ft). There are three gaps in the mountain range: the northernmost Goa Gap , formed 65–80 million years ago (Mya), the oldest and widest Palghat Gap , formed 500 Mya, and the southernmost, narrowest Shencottah Gap . The narrow coastal plain between the Western Ghats and the Arabian Sea
13224-483: Was followed by a Silurian Hot House period. The End-Ordovician extinction , which resulted in 27% of marine invertebrate families and 57% of genera going extinct, occurred during this shift from Ice House to Hot House. By the end of the Ordovician, Cooksonia , a slender, ground-covering plant, became the first known vascular plant to establish itself on land. This first colonisation occurred exclusively around
13340-473: Was formed by the accretion of several cratons (large stable blocks of the Earth's crust), beginning c. 800 to 650 Ma with the East African Orogeny , the collision of India and Madagascar with East Africa, and culminating in c. 600 to 530 Ma with the overlapping Brasiliano and Kuunga orogenies, the collision of South America with Africa, and
13456-540: Was hardly affected. Gondwanatheria is an extinct group of non- therian mammals with a Gondwanan distribution (South America, Africa, Madagascar, India, Zealandia and Antarctica) during the Late Cretaceous and Palaeogene. Xenarthra and Afrotheria , two placental clades, are of Gondwanan origin and probably began to evolve separately c. 105 Ma when Africa and South America separated. The laurel forests of Australia, New Caledonia, and New Zealand have
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