112-531: The sungrebe ( Heliornis fulica ) is a small aquatic gruiform found in the tropical and subtropical Americas from northeastern Mexico to central Ecuador and southern Brazil. It is the only living member of the genus Heliornis . The family Heliornithidae , to which it belongs, contains just two other species: the African finfoot , Podica senegalensis , found in the Afrotropics from Sub-saharan West Africa and
224-617: 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
336-455: A considerable number of living and extinct bird families , with a widespread geographical diversity. Gruiform means "crane-like". Traditionally, a number of wading and terrestrial bird families that did not seem to belong to any other order were classified together as Gruiformes. These include 15 species of large cranes , about 145 species of smaller crakes and rails , as well as a variety of families comprising one to three species , such as
448-585: 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
560-715: 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
672-472: 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
784-589: 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,
896-409: A higher average mass, 130–140 g (4.6–4.9 oz). The male is similar to the female, but has slightly drabber plumage; in particular the male lacks the bright orange-rufous patch on the cheeks that the female displays, and while his lower mandible turns from pale beige to dark red during the breeding season, it does not get as bright as that of the female. On average he is slightly longer and with
1008-507: A male to carry them while diving and flying. The bird appears to have some muscular control over the shape of the pleats, and can restrict or enhance fluid flow into the tissue to make them more or less rigid. Each pouch can hold one or two chicks. It is unknown whether other finfoots share this trait, as it does not persist in prepared skins and would be difficult to spot even in fresh specimens unless one knew to seek it out. Since no other species of bird have been found that have pouches, it
1120-514: 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
1232-623: 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
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#17328696756561344-531: 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
1456-514: 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
1568-808: 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
1680-681: 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
1792-568: A variety of terrestrial and aquatic arthropods, as well as small fish, frogs and lizards. They will also eat some plant matter, including seeds and fruit. Most hunting and foraging takes place on or just above the surface of the water, although they may make short dives after fish and frogs, or hunt from low perches over the water. Sungrebes live at variable, but generally low population densities, and are generally solitary or found in pairs. They do not migrate seasonally, except to move out of drying habitats and into flooding ones within their range. It
1904-459: A wider distribution in the past; a 14 million year-old fossil humerus attributed to Heliornis aff. fulica has been described from the Middle Miocene -aged Pungo River Formation of North Carolina , USA. This is the earliest known finfoot fossil, and its discovery raises questions as to whether the thus-far undiscovered South American ancestors of sungrebes moved into North America well before
2016-517: A wider wingspan 14.1 cm (5.6 in) than the female, but more lightly built with a lower average mass (110-140g). Juveniles have similar plumage to the male, but are slightly smaller, and with a grayer cast to the body feathers and more white on the cheeks and neck. Sungrebes are found in heavily vegetated, mostly freshwater wetland environments, from northeast Mexico south along the Gulf and Caribbean coasts through Panama, where they live throughout
2128-423: Is countershaded slate-gray with a white belly and throat. The bill is slate-gray with a pale yellow tip. Males transfer the young to their pouches soon after hatching and keep them there, feeding them and cleaning out their waste, until they are able to swim and feed independently. For some period of time after this, the chicks continue to follow their father and perhaps their mother, often riding on their back. It
2240-571: Is dependent on the inclusion of one or two specific loci in the analyses. One locus, i.e., mitochondrial DNA , contradicts the strict monophyly of Coronaves (Morgan-Richards et al. 2008), but phylogeny reconstruction based on mitochondrial DNA is complicated by the fact that few families have been studied, the sequences are heavily saturated (with back mutations) at deep levels of divergence, and they are plagued by strong base composition bias. The kagu and sunbittern are one another's closest relatives. It had been proposed (Cracraft 2001) that they and
2352-549: Is difficult to say how this evolved; however, in Jacanas , a tropical wading bird found in the same habitat as finfeet in which males also provide most of the parental care, young are frequently sheltered and even carried by tucking them under the wings and holding them against the body. This could have been the ancestral state for Sungrebes, as well. Sungrebes prefer quiet forest streams and rivers, freshwater ponds, and lakes with thick, overhanging vegetation. Here, they hunt snails and
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#17328696756562464-461: Is not known how far juvenile sungrebes disperse after fledging, nor is it known if one sex preferentially disperses. It might be notable, however, that erratic sungrebes found outside of their known range have tended to be females. There is also no information on life span, age at first breeding, or mortality rates of young. Given that their range is very large and that the species is not directly targeted for human use, BirdLife International (2009)
2576-771: 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
2688-566: 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
2800-537: 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
2912-427: Is unknown how involved mothers are in the care of their young after hatching. The pouch of a male sungrebe is a shallow, ovular pocket formed by pleats of well-muscled skin that extend along the side of the chest under the wings, further buffered by a wall of long, curved feathers growing upwards and backwards from the lower part of the side of the chest. These feathers hold chicks in place during movement, even allowing
3024-755: 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
3136-708: The Aramidae , and even placed the limpkins within Heliornithidae in 1990. However, more recent genetic analyses suggests that limpkins are sister taxa to cranes, the Gruidae , and that finfeet are instead sister taxa to rails, the Rallidae . Other studies suggest that finfeet and the Afro-Madagascan flufftails , a group originally thought to be nested within rails, form a lineage called Sarothruridae that separated from each other at
3248-1006: 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
3360-625: 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,
3472-827: 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
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3584-704: The Canal Zone and Darien , and then along the Pacific coast from Panama through central Ecuador. They are also found throughout the Orinoco and Amazon Watershed , the Pantanal , and the Brazilian Atlantic Rainforests . Aside from Trinidad and Tobago , they are not found in most Caribbean nations, and seem to have difficulty dispersing over long distances of saltwater. Though occasionally recorded at higher elevations,
3696-590: 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
3808-872: The Congo Basin through the Great Lakes ' western shores to Southeast Africa , and the Asian or masked finfoot Heliopais personatus , found from eastern Indomalaya down through Sundaland to the Wallace Line . These waterfowl have broad lobes on their feet, convergent to that of grebes or coots , that they use to propel themselves in the water. They are reclusive birds, preferring well-covered slow-flowing streams and secluded waterways, sometimes swimming partly submerged, like an anhinga . Sungrebes are unique among birds in that males have "pouches", folds of skin under their wings in which they carry their young from hatching until
3920-795: 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 ,
4032-538: The Great American Interchange , or if they instead came across Beringia and then moved into South America when the Isthmus of Panama formed. The phylogenetic divergence patterns of finfeet, which indicate that the sungrebe is most closely related to the Asian finfoot, support the latter theory. The female is a small, slim bird, averaging about 30 cm (12 in) in length. Sungrebes have lobed toes, and
4144-652: 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
4256-541: The Heliornithidae , the limpkin , or the Psophiidae . Other birds have been placed in this order more out of necessity to place them somewhere ; this has caused the expanded Gruiformes to lack distinctive apomorphies . Recent studies indicate that these "odd Gruiformes" are if at all only loosely related to the cranes, rails, and relatives ("core Gruiformes"). There are only two suprafamilial clades (natural groups) among
4368-716: 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
4480-572: The IUNC evaluates the conservation status of the Sungrebe as of Least Concern . Their northward expansion seems to justify that status. However, very little is known about any population of sungrebe, including the nature of their risk factors and whether the range of the Sungrebe consists of a single large population at low risk or a series of genetically distinct populations at higher risk. Further, tropical wetland areas are attractive targets for agricultural usage and hydroelectric projects . The Sungrebe's preference for heavy cover and tendency to avoid
4592-440: The Indian Subcontinent . Gondwana 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
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4704-414: 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,
4816-422: 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
4928-481: 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
5040-481: 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
5152-483: 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
5264-499: 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 ,
5376-404: 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
5488-442: 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
5600-422: 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
5712-403: 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
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#17328696756565824-403: 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
5936-400: The 1940s had established populations throughout Veracruz and into San Luis Potosí . They are now expanding their range further north in Tamaulipas , and an individual was sighted on 13 November 2008 on the Marsh Loop at Bosque del Apache National Wildlife Refuge in New Mexico, USA, the first historical record of sungrebes in the United States. The sungrebe has a mating season that begins in
6048-444: The Atlantic from Africa, or having evolved on Gondwana , separated with the shifting of the continents, and moved north into Laurasia from there. This would also explain the absence of finfeet from Australia , and the success of the Sungrebe at colonizing the continental Neotropics while failing to colonize any major Caribbean islands that do not have glacial land bridges to the mainland. The genus Heliornis appears to have had
6160-502: 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,
6272-405: 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:
6384-448: 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
6496-400: 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
6608-493: The French naturalist Pierre Bonnaterre in 1791 with the sungrebe as the type species . The name of the genus combines the Ancient Greek hēlios meaning "sun" and ornis meaning "bird". The specific epithet fulica is Latin for "coot". No subspecies are recognised. There is some debate where the finfoot family, Heliornithidae , fits within Gruiformes. The Sibley–Ahlquist taxonomy of birds , based on DNA-DNA Hybridization , suggested that they are sister taxa to limpkins,
6720-409: The Gruiformes based on large DNA–DNA hybridization distances to other supposed Gruiformes. However, it was not until the work of Paton et al. (2004) and Fain and Houde (2004, 2006) that the correct placement of buttonquails within the shorebirds (order Charadriiformes) was documented on the basis of phylogenetic analysis of multiple genetic loci. Using 12S ribosomal DNA sequences, Houde et al. (1997) were
6832-445: The Gruiformes, e.g., Ergilornithidae, Phorusrhacidae, Messelornithidae, Eogruidae, Idiornithidae, Bathornithidae, to name just a few (see below). Though some of these are superficially 'crane-like' and the possibility exists that some may even be related to extant families traditionally included in the Gruiformes, there are no completely extinct families that can be confidently assigned to core-Gruiformes. The traditional order Gruiformes
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#17328696756566944-446: 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
7056-406: 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,
7168-422: 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
7280-405: 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
7392-443: 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
7504-441: 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
7616-456: 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
7728-465: 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
7840-408: 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
7952-401: 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
8064-425: The bare skin of their feet and legs are boldly banded in yellow and black. The body plumage is mostly varying shades of reddish brown, while the head and neck are strikingly patterned with a black crown and nape and white stripes along the sides of its neck, as well as a white throat and chin. The long tail (almost a third of the total length) extends well beyond the body in flight, and sits fanned out on or just below
8176-763: 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
8288-768: The birds traditionally classified as Gruiformes. Rails ( Rallidae ), flufftails ( Sarothruridae ), finfoots and sungrebe ( Heliornithidae ), adzebills ( Aptornithidae ), trumpeters ( Psophiidae ), limpkin ( Aramidae ), and cranes ( Gruidae ) compose the suborder Grues and are termed "core-Gruiformes". These are the only true Gruiformes. The suborder Eurypygae includes the kagu (Rhynochetidae) and sunbittern (Eurypygidae). These are not even remotely related to Grues. The families of mesites or roatelos ( Mesitornithidae ), button-quails ( Turnicidae ), Australian plains-wanderer ( Pedionomidae ), seriemas ( Cariamidae ), and bustards ( Otididae ) each represent distinct and unrelated lineages. Many families known only from fossils have been assigned to
8400-603: The chicks are able to swim for themselves. This has led to them being called "Marsupial Birds" The sungrebe was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1781 in his Histoire Naturelle des Oiseaux from a specimen collected in Cayenne , French Guiana . The bird was also illustrated in a hand-coloured plate engraved by François-Nicolas Martinet in the Planches Enluminées D'Histoire Naturelle which
8512-526: 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
8624-723: 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
8736-424: 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
8848-800: 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
8960-544: 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
9072-596: The end of the Eocene , probably in Africa. Sarothruridae, in turn, is considered a sister clade to Rallidae. Within Heliornithidae, sungrebes are sister to the Asian finfoot , rather than the geographically closer African finfoot , according to the results of both Mitochondrial and Nuclear DNA sequencing . This adds credence to the idea that finfeet moved from an African origin into Eurasia and then across Beringia and through North America to reach South America, rather than coming across
9184-962: 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
9296-550: 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
9408-554: 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
9520-500: The first to present molecular genetic evidence of gruiform polyphyly , although apparently they were not convinced by it. However, on the basis of numerous additional sequence data, it has been shown decisively that the traditionally recognized Gruiformes consist of five to seven unrelated clades (Fain and Houde 2004, Ericson et al. 2006, Hackett et al. 2008). Fain and Houde (2004) proposed that Neoaves are divisible into two clades, Metaves and Coronaves, although it has been suggested from
9632-510: 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
9744-518: 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
9856-670: 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
9968-584: The known families and that may occupy a more basal position: Other even more enigmatic fossil birds and five living families are occasionally suggested to belong into this order, such as the proposed Late Cretaceous family Laornithidae and the following taxa: Gondwana#Break-up 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
10080-833: 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
10192-503: 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
10304-417: The male and female birds take part in the nest building, which typically consists of twigs, reeds, and dried leaves. The nest is a flimsy platform placed about a meter above the water's surface. There are usually two to four eggs in a clutch. They are round in shape with a buffy white to pale cinnamon base color, with irregularly-shaped dark cinnamon, ruddy brown, and pale purple sports scattered uniformly over
10416-445: The middle of April during the "early wet season "; breeding is correlated with rainfall and corresponding high water levels that flood habitat and bring the sort of low-overhanging vegetation that subgrebes like to build their nest in. The bolder coloration of the females, as well as their greater mass and the males' role as primary caregiver for the young, suggest that females court the males, although this has not yet been observed. Both
10528-587: 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
10640-519: The presence of humans may limit its ability to cope with the rapid urbanization of Latin America. Nevertheless, Sungrebes seem to be faring much better than their relatives, who live in much more population-dense, much less well protected or environmentally regulated parts of the world. Gruiformes Some 5–10 living, see article text. The Gruiformes ( / ˈ ɡ r uː ɪ f ɔːr m iː z / GROO -ih-for-meez ) are an order containing
10752-542: 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
10864-792: The recently extinct adzebills (family Aptornithidae) from New Zealand constitute a distinct Gondwanan lineage. However, sunbittern and kagu are believed to have diverged from one another long after the break-up of Gondwanaland and the adzebills are in fact members of the Grues (Houde et al. 1997, Houde 2009). The seriemas and bustards represent distinct lineages within neoavian waterbirds. Psophiidae – trumpeters (3 species) Aramidae – limpkin Gruidae – cranes (15 species) Rallidae – rails, crakes and coots (152 species) Heliornithidae – finfoots (3 species) Sarothruridae – flufftails (15 species) Gruiformes When considered to be monophyletic, it
10976-513: 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,
11088-746: 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
11200-528: The start that Metaves may be paraphyletic (Fain and Houde 2004, Ericson et al. 2006, Hackett et al. 2008). Sunbittern, kagu, and mesites all group within Metaves but all the other lineages of "Gruiformes" group either with a collection of waterbirds or landbirds within Coronaves. This division has been upheld by the combined analysis of as many as 30 independent loci (Ericson et al. 2006, Hackett et al. 2008), but
11312-648: 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
11424-399: 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
11536-634: The sungrebe is usually associated with lowlands from sea level to around 500 meters. They are residents throughout their range; they do not seem to migrate. Based on the fossil record, sungrebes or a close relative appear to have ranged as far north as the southeastern United States during the Miocene , despite being only restricted to the Neotropics today. Sungrebes seem to be expanding the northern limit of their range in northeastern Mexico. They were historically found no farther north than central Veracruz , but by
11648-659: The surface at variable densities from egg to egg. The eggs hatch after an unusually short incubation period of only 10 to 11 days. Both sexes share responsibility in the incubation of the eggs; the female sits on the nest for most of the daylight hours and throughout the night, while male incubates them during the middle part of the day. Unlike their close relatives, the African and Asian finfoot, whose chicks are said to be precocial , sungrebe chicks are altricial upon hatching, blind and defenseless with only sparse down and poorly matured feet and bill. They are covered with fuzzy down that
11760-448: The surface of the water while the bird swims. Females have a rufous patch on the side of the face that brightens to a cinnamon-orange color during the breeding season. Also during the breeding season, her eye ring becomes brighter in color and her lower mandible goes from dark red to bright scarlet. Slightly shorter on average than the male, with a slightly shorter wingspan, 13.77 cm (5.42 in), but slightly more powerfully-built with
11872-499: The traditional Gruiformes. They recognized that the Australian plains-wanderer (family Pedionomidae) was actually a member of the shorebirds (order Charadriiformes) based on skeletal characters. This was confirmed by Sibley and Ahlquist (1990) based on DNA–DNA hybridization and subsequently by Paton et al. (2003), Paton and Baker (2006) and Fain and Houde (2004, 2006). Sibley and Ahlquist furthermore removed button-quails (Turnicidae) from
11984-613: 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
12096-417: Was assumed that Gruiformes was among the more ancient of avian lineages. The divergence of "gruiforms" among "Metaves" and "Coronaves" is proposed to be the first divergence among Neoaves, far predating the Cretaceous–Paleogene extinction event c. 66 mya (Houde 2009). No unequivocal basal gruiforms are known from the fossil record. However, there are several genera that are not unequivocally assignable to
12208-451: Was established by the influential German avian comparative anatomist Max Fürbringer (1888). Over the decades, many ornithologists suggested that members of the order were in fact more closely related to other groups (reviewed by Olson 1985, Sibley and Ahlquist 1990). For example, it was thought that sunbittern might be related to herons and that seriemas might be related to cuckoos. Olson and Steadman (1981) were first to correctly disband any of
12320-477: 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
12432-533: 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
12544-449: Was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text. Neither the plate caption nor Buffon's description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name Colymbus fulica in his catalogue of the Planches Enluminées . The sungrebe is now the only species placed in the genus Heliornis that was erected by
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