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130-490: The oilbird ( Steatornis caripensis ), locally known as the guácharo , is a bird species found in the northern areas of South America including the Caribbean island of Trinidad . It is the only species in the genus Steatornis , the family Steatornithidae , and the order Steatornithiformes . Nesting in colonies in caves, oilbirds are nocturnal feeders on the fruits of the oil palm and tropical laurels . They are

260-802: A considerably smaller portion in the Northern Hemisphere . It can also be described as the southern subregion of the Americas . South America is bordered on the west by the Pacific Ocean and on the north and east by the Atlantic Ocean ; North America and the Caribbean Sea lie to the northwest. The continent includes twelve sovereign states : Argentina , Bolivia , Brazil , Chile , Colombia , Ecuador , Guyana , Paraguay , Peru , Suriname , Uruguay , and Venezuela ; two dependent territories :

390-608: A different balance between their metabolic reactions from those organisms that live in the epipelagic zone. David Wharton, author of Life at the Limits: Organisms in Extreme Environments , notes "Biochemical reactions are accompanied by changes in volume. If a reaction results in an increase in volume, it will be inhibited by pressure, whereas, if it is associated with a decrease in volume, it will be enhanced". This means that their metabolic processes must ultimately decrease

520-457: A few of the characteristics that deep-sea fishes have for this purpose. The gulper eel is one example of an organism that displays these characteristics. Fish in the different pelagic and deep-water benthic zones are physically structured, and behave in ways, that differ markedly from each other. Groups of coexisting species within each zone all seem to operate in similar ways, such as the small mesopelagic vertically migrating plankton-feeders,

650-511: A fish at the bottom of the bathypelagic zone , this pressure amounts to about 400 atm (40 MPa, or nearly 6000 pounds per square inch). Deep-sea organisms possess adaptations at cellular and physiological levels that allow them to survive in environments of great pressure. Not having these adaptations limits the depths at which shallow-water species can operate. High levels of external pressure affects how metabolic processes and biochemical reactions proceed. The equilibrium of many chemical reactions

780-502: A flattened, powerfully hooked, beak surrounded by deep chestnut rictal bristles up to 5 centimetres (2.0 in) long. The adult weighs 350–475 g (12.3–16.8 oz) but the chicks can weigh considerably more, at up to 600 grams (21 oz), when their parents feed them a good deal of fruit before they fly. The feathers of the oilbird are soft like those of many nightbirds, but not as soft as those of owls or nightjars, as they do not need to be silent like predatory species. The oilbird

910-669: A fleet to reach Peru by sea, and sought the military support of various rebels from the Viceroyalty of Peru. In 1822 the two men met at the Guayaquil Conference in Ecuador, where they failed to agree on governance strategies for the liberated nations. Two years later Bolívar's forces beat the Spanish at the Battle of Ayacucho , securing the independence of Peru and the rest of South America. In

1040-399: A habitat with very little food or available energy, not even sunlight, only bioluminescence. Their bodies are elongated with weak, watery muscles and skeletal structures. Since so much of the fish is water, they are not compressed by the great pressures at these depths. They often have extensible, hinged jaws with recurved teeth. They are slimy, without scales . The central nervous system

1170-407: A high pressure and low temperature environment favors negative enthalpy changes and reduced dependence on entropy-driven reactions. From a structural standpoint, globular proteins of deep-sea fish due to the tertiary structure of G-actin are relatively rigid compared to those of surface level fish. The fact that proteins in deep-sea fish are structurally different from surface fish is apparent from

1300-408: A higher fluidity than their sea-level counterparts. Ten orders, thirteen families and about 200 known species of deep-sea fish have evolved a gelatinous layer below the skin or around the spine, which is used for buoyancy, low-cost growth and to increase swimming efficiency by reducing drag. Deep-sea species exhibit lower changes of entropy and enthalpy compared to surface level organisms, since

1430-489: A large mouth with sharp teeth for grabbing large prey and overlapping gill rakers which prevent small prey that have been swallowed from escaping. It is not easy finding a mate in this zone. Some species depend on bioluminescence , where bioluminescent patterns are unique to specific species. Others are hermaphrodites , which doubles their chances of producing both eggs and sperm when an encounter occurs. The female anglerfish releases pheromones to attract tiny males. When

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1560-454: A long history of colonialism , the overwhelming majority of South Americans speak Spanish or Portuguese , and societies and states are rich in Western traditions . Relative to Africa, Asia, and Europe, post-1900 South America has been a peaceful continent with few wars, although high rates of violent crime remain a concern in some countries. South America occupies the southern portion of

1690-422: A long evolution in deep-sea environments. In contrast, deep-water benthic species, are in orders that include many related shallow-water fishes. Below the epipelagic zone, conditions change rapidly. Between 200 m and about 1000 m, light continues to fade until there is almost none. Temperatures fall through a thermocline to temperatures between 3.9 °C (39 °F) and 7.8 °C (46 °F). This

1820-413: A male finds her, he bites on to her and never lets go. When a male of the anglerfish species Haplophryne mollis bites into the skin of a female, he releases an enzyme that digests the skin of his mouth and her body, fusing the pair to the point where the two circulatory systems join up. The male then atrophies into nothing more than a pair of gonads . This extreme sexual dimorphism ensures that, when

1950-653: A part of Oceania, also administered by Chile), the Galápagos Islands (administered by Ecuador , sometimes considered part of Oceania), and Tierra del Fuego (split between Argentina and Chile). In the Atlantic Ocean, Brazil administers Fernando de Noronha , Trindade and Martim Vaz , and the Saint Peter and Saint Paul Archipelago , while the Falkland Islands (Spanish: Islas Malvinas ) and South Georgia and

2080-502: A population of a hundred birds in a canyon with ledges protected by vegetation. Some smaller caves and gorges are used only for roosting. While it was once thought that oilbirds always or nearly always roosted in caves, canyons or gullies, researchers placing GPS trackers on non-breeding birds found that they regularly roost in trees in the forest as well as in caves. It is a seasonal migrant across some of its range, moving from its breeding caves in search of fruit trees. It has occurred as

2210-573: A rare vagrant to Costa Rica , Panama and Aruba . The Guácharo Cave (Oilbird Cave), in the mountainous Caripe district of northern Monagas , Venezuela , is where Alexander von Humboldt first studied the species. Oilbirds are nocturnal . During the day the birds rest on cave ledges and leave at night to find fruit outside the cave. It was once thought that oilbirds only roosted in caves, and indeed never saw daylight, but studies using GPS/acceleration loggers found that non-breeding birds only roosted in caves or other rock shelters one night in three,

2340-481: A site called Chavín de Huantar in modern Peru at an elevation of 3,177 meters (10,423 ft). Chavín civilization spanned 900 BC to 300 BC. In the central coast of Peru, around the beginning of the 1st millennium AD, Moche (100 BC – 700 AD, at the northern coast of Peru), Paracas and Nazca (400 BC – 800 AD, Peru) cultures flourished with centralized states with permanent militia improving agriculture through irrigation and new styles of ceramic art. At

2470-464: A species of barreleye , is the only vertebrate known to employ a mirror, as opposed to a lens, to focus an image in its eyes. Sampling by deep trawling indicates that lanternfish account for as much as 65% of all deep-sea fish biomass . Indeed, lanternfish are among the most widely distributed, populous, and diverse of all vertebrates , playing an important ecological role as prey for larger organisms. The estimated global biomass of lanternfish

2600-670: A subtropical climate of the dinaric type. At the highest points of the Andean region, climates are colder than the ones occurring at the highest point of the Norwegian fjords. In the Andean plateaus, the warm climate prevails, although it is tempered by the altitude, while in the coastal strip, there is an equatorial climate of the Guinean type. From this point until the north of the Chilean coast appear, successively, Mediterranean oceanic climate , temperate of

2730-512: Is 550–660 million tonnes , several times the entire world fisheries catch. Lanternfish also account for much of the biomass responsible for the deep scattering layer of the world's oceans. Bigeye tuna are an epipelagic/mesopelagic species that eats other fish. Satellite tagging has shown that bigeye tuna often spend prolonged periods cruising deep below the surface during the daytime, sometimes making dives as deep as 500 metres (1,640 ft). These movements are thought to be in response to

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2860-400: Is a heap of droppings, usually above water—either a stream or the sea—on which 2–4 glossy white eggs are laid which soon become stained brown. These are rounded but with a distinctly pointed smaller end and average 41.2 millimetres (1.62 in) by 33.2 millimetres (1.31 in). The squabs become very fat before fledging, weighing around a third more than the adult birds. The Guácharo Cave

2990-504: Is a protein found in the eye’s rod cells that helps animals see in dim light. While most vertebrates usually have one Rh1 opsin gene, some deep-sea fish have several Rh1 genes, and one species, the silver spinyfin ( Diretmus argenteus ), has 38. This proliferation of Rh1 genes may help deep-sea fish to see in the depths of the ocean. Also, to avoid predation, many species are dark to blend in with their environment. Many deep-sea fish are bioluminescent , with extremely large eyes adapted to

3120-515: Is because the most extensive part of the continent is in the equatorial zone (the region has more areas of equatorial plains than any other region), therefore giving the Southern Cone more oceanic influence, which moderates year round temperatures. The average annual temperatures in the Amazon basin oscillate around 27 °C (81 °F), with low thermal amplitudes and high rainfall indices. Between

3250-460: Is by far the most populous South American country, with almost half of the continent's population, followed by Colombia, Argentina, Venezuela, and Peru. In recent decades, Brazil has also generated half of the continent's GDP and has become the continent's first regional power. Most of the population lives near the continent's western or eastern coasts while the interior and the far south are sparsely populated. The geography of western South America

3380-521: Is completely aphotic. Conditions are somewhat uniform throughout these zones; the darkness is complete, the pressure is crushing, and temperatures, nutrients and dissolved oxygen levels are all low. Bathypelagic fish have special adaptations to cope with these conditions – they have slow metabolisms and unspecialized diets, being willing to eat anything that comes along. They prefer to sit and wait for food rather than waste energy searching for it. The behaviour of bathypelagic fish can be contrasted with

3510-403: Is confined to the lateral line and olfactory systems, the eyes are small and may not function, and gills , kidneys and hearts, and swim bladders are small or missing. These are the same features found in fish larvae , which suggests that during their evolution, bathypelagic fish have acquired these features through neoteny . As with larvae, these features allow the fish to remain suspended in

3640-475: Is disturbed by pressure, and pressure can inhibit processes which result in an increase in volume. Water, a key component in many biological processes, is very susceptible to volume changes, mainly because constituents of cellular fluid have an effect on water structure. Thus, enzymatic reactions that induce changes in water organization effectively change the system's volume. Proteins responsible for catalyzing reactions are typically held together by weak bonds and

3770-442: Is dominated by rod cells , 1,000,000 rods per mm, the highest density of any vertebrate eye, which are organised in layers, an arrangement unique among birds but shared by deep-sea fish . They have low numbers of cone cells , and the whole arrangement would allow them to capture more light in low light conditions but probably have poor vision in daylight. Although they have specially adapted vision to forage by sight, they are among

3900-597: Is dominated by the Andes mountains; in contrast, the eastern part contains both highland regions and vast lowlands where rivers such as the Amazon , Orinoco and Paraná flow. Most of the continent lies in the tropics, except for a large part of the Southern Cone located in the middle latitudes . The continent's cultural and ethnic outlook has its origin with the interaction of Indigenous peoples with European conquerors and immigrants and, more locally, with African slaves . Given

4030-561: Is exemplified between the species C. acrolepis (around 2000 m deep) and its hadalpelagic counterpart C. armatus (around 4,000 metres (13,123 ft) deep), where the Na+/K+ -ATPases of C. armatus are much less sensitive to pressure. This resistance to pressure can be explained by adaptations in the protein and lipid moieties of Na+/K+ -ATPase. Sampling via deep trawling indicates that lanternfish account for as much as 65% of all deep-sea fish biomass . Indeed, lanternfish are among

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4160-407: Is explained by the likewise abundance of prey species which are also attracted to the structures. Hydrostatic pressure increases by 1 atm (0.1 MPa) for every 10 m (32.8 ft) in depth. Deep-sea organisms have the same pressure within their bodies as is exerted on them from the outside, so they are not crushed by the extreme pressure. Their high internal pressure, however, results in

4290-541: Is mainly reddish-brown with white spots on the nape and wings. Lower parts are cinnamon-buff with white diamond-shaped spots edged in black, these spots start small towards the throat and get larger towards the back. The stiff tail feathers are a rich brown spotted with white on either side. The feet are small and almost useless, other than for clinging to vertical surfaces. The long wings have evolved to make it capable of hovering and twisting flight, which enables it to navigate through restricted areas of its caves. For example,

4420-547: Is no light in the deep sea (aphotic), there is a lack of primary producers. Therefore, most organisms in the bathypelagic rely on the marine snow from regions higher in the vertical column. Some deep-sea pelagic groups, such as the lanternfish , ridgehead , marine hatchetfish , and lightfish families, are sometimes termed pseudoceanic because, rather than having an even distribution in open water, they occur in significantly higher abundances around structural oases, notably seamounts and over continental slopes . The phenomenon

4550-595: Is now Colombia. They established the Muisca Confederation of many clans, or cacicazgos , that had a free trade network among themselves. Many were goldsmiths and farmers. Other important Pre-Columbian cultures include: the Cañaris (in south central Ecuador), Chimú Empire (1300–1470, Peruvian northern coast), Chachapoyas , and the Aymaran kingdoms (1000–1450, Western Bolivia and southern Peru). Holding their capital at

4680-476: Is one of the most biodiverse continents on Earth. It is home to many unique species of animals including the llama , anaconda , piranha , jaguar , vicuña , and tapir , and to one of the largest known insects in the world, the Titan beetle . The Amazon rainforests possess high biodiversity , with Brazil estimated to contain 10% of Earth's species . 83% of South America's large mammals ( megafauna ) became extinct at

4810-596: Is the twilight or mesopelagic zone. Pressure continues to increase, at the rate of one atm (0.1 MPa) every 10 m (32.8 ft), while nutrient concentrations fall, along with dissolved oxygen and the rate at which the water circulates. Sonar operators, using the newly developed sonar technology during World War II , were puzzled by what appeared to be a false sea floor 300–500 metres (984–1,640 ft) deep by day, and less deep at night. This turned out to be due to millions of marine organisms, most particularly small mesopelagic fish, with swim bladders that reflected

4940-571: Is the largest country in South America, covering a little less than half of the continent's land area and encompassing around half of the continent's population. The remaining countries and territories are divided among four subregions : the Andean states , Caribbean South America , The Guianas , and the Southern Cone . Physiographically, South America also includes some of the nearby islands. The Dutch ABC islands ( Aruba , Bonaire , and Curaçao ),

5070-510: The Altiplano , Tiahuanaco or Tiwanaku (100 BC – 1200 AD, Bolivia) managed a large commercial network based on religion. Around the 7th century, both Tiahuanaco and Wari or Huari Empire (600–1200, Central and northern Peru) expanded its influence to all the Andean region, imposing the Huari urbanism and Tiahuanaco religious iconography. The Muisca were the main indigenous civilization in what

5200-572: The Archipelago of San Andrés, Providencia and Santa Catalina ( San Andrés Island , Providencia Island , and Santa Catalina Island etc., which are administered by Colombia ) are politically parts of South American countries but physiographically parts of North America. Other islands often associated with geopolitical South America are the Chiloé Archipelago and Robinson Crusoe Island (both administered by Chile), Easter Island (culturally

5330-802: The Atacama Desert ; the wettest place on earth, López de Micay in Colombia; the largest rainforest, the Amazon rainforest ; the highest capital city, La Paz , Bolivia ; the highest commercially navigable lake in the world, Lake Titicaca ; and, excluding research stations in Antarctica , the world's southernmost permanently inhabited community, Puerto Toro , Chile. South America's major mineral resources are gold, silver, copper, iron ore, tin , and petroleum. These resources have brought high income to its countries, especially in times of war or of rapid economic growth by industrialized countries elsewhere. However,

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5460-686: The Bering Land Bridge (now the Bering Strait ) at least 15,000 years ago from the territory that is present-day Russia. They migrated south through North America, and eventually reached South America through the Isthmus of Panama . Amongst the oldest evidence for human presence in South America is the Monte Verde II site in Chile, suggested to date to around 14,500 years ago. From around 13,000 years ago,

5590-568: The Caribbean colonies and Brazil, as European nations built up economically slave-dependent colonies in the New World . Nearly 40% of all African slaves trafficked to the Americas went to Brazil. An estimated 4.9 million slaves from Africa came to Brazil during the period from 1501 to 1866. In contrast to other European colonies in the Americas which mainly used the labor of African slaves, Spanish colonists mainly enslaved indigenous Americans. In 1750,

5720-825: The Carrasco National Park in Bolivia . Dunston Cave , at the Asa Wright Nature Centre in Trinidad , is home to about 200 nesting pairs. The species is classified as 'Least Concern' by the IUCN red list as of October 2016, despite a decreasing population. [REDACTED] South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere , with

5850-1000: The Falkland Islands and South Georgia and the South Sandwich Islands ; and one internal territory : French Guiana . The ABC islands of the Dutch Caribbean (north of Venezuela in the Leeward Antilles ), Ascension Island (a part of Saint Helena, Ascension and Tristan da Cunha ), Bouvet Island (a dependency of Norway ), Panama , and the Caribbean island country of Trinidad and Tobago may also be considered parts of South America. South America has an area of 17,840,000 square kilometers (6,890,000 sq mi). Its population as of 2021 has been estimated at more than 434 million. South America ranks fourth in area (after Asia, Africa, and North America) and fifth in population (after Asia, Africa, Europe, and North America). Brazil

5980-465: The Fishtail projectile point style became widespread across South America, with its disappearance around 11,000 years ago coincident with the disappearance of South America's megafauna. Maize was present in northern South America by around 6,000 years ago. By 2000 BC, many agrarian communities had been settled throughout the Andes and the surrounding regions. Fishing became a widespread practice along

6110-467: The Fortaleza area, contemporaneous with the pyramids of Ancient Egypt , one of the oldest-known civilizations in the Americas and one of the six sites where civilization separately originated in the ancient world. Caral–Supe governing class established a trade network and developed agriculture then followed by Chavín by 900 BC, according to some estimates and archaeological finds. Artifacts were found at

6240-688: The Maracaibo Lake and the mouth of the Orinoco, predominates an equatorial climate of the type Congolese, that also includes parts of the Brazilian territory. The east-central Brazilian plateau has a humid and warm tropical climate. The northern and eastern parts of the Argentine pampas have a humid subtropical climate with dry winters and humid summers of the Chinese type, while the western and eastern ranges have

6370-463: The Monte Solane lagerstatte of early Eocene Italy, which preserves a bathypelagic habitat likely deposited 300–600 meters under the sea, as well as the late Eocene Pabdeh Formation of Iran . The deep-sea environments preserved by both formations are apparent through their abundance of fossil stomiiform fish. Notable Neogene formations that preserve fossils of deep-sea bony fish are known from

6500-585: The Orinoco Llanos and in the Guianas Plateau , the precipitation levels go from moderate to high. The Pacific coast of Colombia and northern Ecuador are rainy regions, with Chocó in Colombia being the rainiest place in the world along with the northern slopes of Indian Himalayas. The Atacama Desert, along this stretch of coast, is one of the driest regions in the world. The central and southern parts of Chile are subject to extratropical cyclones , and most of

6630-539: The Portuguese Crown abolished the enslavement of indigenous peoples in colonial Brazil , under the belief that they were unfit for labor and less effective than enslaved Africans. Enslaved Africans were brought to the Americas on slave ships , under inhuman conditions and ill-treatment, and those who survived were sold in slave markets . After independence, all South American countries maintained slavery for some time. The first South American country to abolish slavery

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6760-705: The Portuguese Kingdom of Brazil , Dom Pedro I (also Pedro IV of Portugal), son of the Portuguese King Dom João VI , proclaimed the independent Kingdom of Brazil in 1822, which later became the Empire of Brazil . Despite the Portuguese loyalties of garrisons in Bahia , Cisplatina and Pará , independence was diplomatically accepted by Portugal in 1825, on condition of a high compensation paid by Brazil mediated by

6890-526: The Riograndense Republic ). Deep-sea fish Deep-sea fish are fish that live in the darkness below the sunlit surface waters, that is below the epipelagic or photic zone of the sea . The lanternfish is, by far, the most common deep-sea fish. Other deep-sea fishes include the flashlight fish , cookiecutter shark , bristlemouths , anglerfish , viperfish , and some species of eelpout . Only about 2% of known marine species inhabit

7020-641: The South American Plate . South America is home to several superlatives, including the world's highest uninterrupted waterfall , Angel Falls in Venezuela; the highest single-drop waterfall Kaieteur Falls in Guyana; the largest river by volume, the Amazon River ; the longest mountain range, the Andes (whose highest mountain is Aconcagua at 6,962 m or 22,841 ft); the driest non-polar place on earth,

7150-588: The Spanish American wars of independence between the patriots, who promoted such autonomy, and the royalists , who supported Spanish authority over the Americas. The Juntas, in both Spain and the Americas, promoted the ideas of the Enlightenment . Five years after the beginning of the war, Ferdinand VII returned to the throne and began the Absolutist Restoration , as the royalists got the upper hand in

7280-485: The abyssal plain of the former Piemont-Liguria Ocean . Prior to the discovery of these fossils, there was no evidence for deep-sea bony fish older than 50 million years in the Paleogene . The Cretaceous origin for most modern deep-sea fish has been further affirmed with phylogenetic studies such as those of aulopiform fish, which indicate that many deep-sea lineages of these groups originated around this time. Although

7410-452: The generic name Steatornis means 'fat bird', in reference to the fatness of the chicks. The oilbird is called a guácharo or tayo in Spanish , both terms being of indigenous origin. In Trinidad it was sometimes called diablotin (French for 'little devil'), presumably referring to its loud cries, which have been likened to those of tortured men. The common name oilbird comes from

7540-501: The inner ear , which responds to sound, and the lateral line , which responds to changes in water pressure. The olfactory system can also be important for males who find females by smell. Bathypelagic fish are black, or sometimes red, with few photophores . When photophores are used, it is usually to entice prey or attract a mate. Because food is so scarce, bathypelagic predators are not selective in their feeding habits, but grab whatever comes close enough. They accomplish this by having

7670-489: The king penguin . Although these fish are plentiful and prolific, currently only a few commercial lanternfish fisheries exist: these include limited operations off South Africa , in the sub-Antarctic , and in the Gulf of Oman . A 2006 study by Canadian scientists has found five species of deep-sea fish – blue hake , spiny eel – to be on the verge of extinction due to the shift of commercial fishing from continental shelves to

7800-494: The mesopelagic (200–1,000 metres (656–3,281 ft) deep) zone as well. The mesopelagic zone is the disphotic zone, meaning light there is minimal but still measurable. The oxygen minimum layer exists somewhere between a depth of 700 metres (2,297 ft) and 1,000 metres (3,281 ft) deep depending on the place in the ocean. This area is also where nutrients are most abundant. The bathypelagic and abyssopelagic zones are aphotic , meaning that no light penetrates this area of

7930-712: The native populations had no immune resistance – caused large-scale depopulation of the native population under Spanish control. Systems of forced labor, such as the haciendas and mining industry's mit'a also contributed to the depopulation. After this, enslaved Africans , who had developed immunities to these diseases, were quickly brought in to replace them. The Spaniards were committed to converting their native subjects to Christianity and were quick to purge any native cultural practices that hindered this end; however, many initial attempts at this were only partially successful, as native groups simply blended Catholicism with their established beliefs and practices. Furthermore,

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8060-417: The order Caprimulgiformes . However, the nightjars and their relatives are insectivores while the oilbird is a specialist fructivore , and it is sufficiently distinctive to be placed in a family (Steatornithidae) and suborder (Steatornithes) of its own. Some research indicates that it should even be considered a distinct order (Steatornithiformes). The specific name caripensis means 'of Caripe ', and

8190-414: The pelagic environment. This means that they live in the water column as opposed to the benthic organisms that live in or on the sea floor. Deep-sea organisms generally inhabit bathypelagic (1,000–4,000 metres (3,281–13,123 ft) deep) and abyssopelagic (4,000–6,000 metres (13,123–19,685 ft) deep) zones. However, characteristics of deep-sea organisms, such as bioluminescence can be seen in

8320-419: The piscivores have larger mouths and coarser gill rakers. Mesopelagic fish are adapted for an active life under low light conditions. Most of them are visual predators with large eyes. Some of the deeper water fish have tubular eyes with big lenses and only rod cells that look upwards. These give binocular vision and great sensitivity to small light signals. This adaptation gives improved terminal vision at

8450-732: The Americas. The continent is generally delimited on the northwest by the Darién watershed along the Colombia–Panama border , although some may consider the border instead to be the Panama Canal . Geopolitically and geographically, all of Panama – including the segment east of the Panama Canal in the isthmus – is typically included in North America alone and among the countries of Central America . Almost all of mainland South America sits on

8580-666: The Argentine Patagonia is desert . In the Pampas of Argentina, Uruguay and South of Brazil the rainfall is moderate, with rains well distributed during the year. The moderately dry conditions of the Chaco oppose the intense rainfall of the eastern region of Paraguay. In the semiarid coast of the Brazilian Northeast the rains are linked to a monsoon regime. Important factors in the determination of climates are sea currents, such as

8710-726: The Breton type and, already in Tierra del Fuego , cold climate of the Siberian type. The distribution of rainfall is related to the regime of winds and air masses. In most of the tropical region east of the Andes, winds blowing from the northeast, east and southeast carry moisture from the Atlantic, causing abundant rainfall. However, due to a consistently strong wind shear and a weak Intertropical Convergence Zone , South Atlantic tropical cyclones are rare. In

8840-697: The Miocene of Italy, Japan, and California. In the deep ocean, the waters extend far below the epipelagic zone, and support very different types of pelagic fishes adapted to living in these deeper zones. In deep water, marine snow is a continuous shower of mostly organic detritus falling from the upper layers of the water column. Its origin lies in activities within the productive photic zone . Marine snow includes dead or dying plankton , protists ( diatoms ), fecal matter, sand, soot and other inorganic dust. The "snowflakes" grow over time and may reach several centimetres in diameter, travelling for weeks before reaching

8970-454: The Na+/K+ -ATPase reaction induces an expansion in the bilayer surrounding the protein, and therefore an increase in volume. An increase in volume makes Na+/K+ -ATPase reactivity susceptible to higher pressures. Even though the Na+/K+ -ATPase activity per gram of gill tissue is lower for deep-sea fishes, the Na+/K+ -ATPases of deep-sea fishes exhibit a much higher tolerance of hydrostatic pressure compared to their shallow-water counterparts. This

9100-447: The South Sandwich Islands ( biogeographically and hydrologically associated with Antarctica) have been administered as two British Overseas Territories under the Crown , whose sovereignty over the islands is disputed by Argentina . An isolated volcanic island on the South American Plate , Ascension Island is geologically a part of South America. Administered as a dependency of Saint Helena, Ascension and Tristan da Cunha ,

9230-830: The Spaniards brought their language to the degree they did with their religion, although the Roman Catholic Church 's evangelization in Quechua , Aymara , and Guaraní actually contributed to the continuous use of these native languages albeit only in the oral form. Eventually, the natives and the Spaniards interbred, forming a mestizo class. At the beginning, many mestizos of the Andean region were offspring of Amerindian mothers and Spanish fathers. After independence, most mestizos had native fathers and European or mestizo mothers. Many native artworks were considered pagan idols and destroyed by Spanish explorers; this included many gold and silver sculptures and other artifacts found in South America, which were melted down before their transport to Spain or Portugal. Spaniards and Portuguese brought

9360-530: The Spanish and Portuguese colonies. First, Napoleon invaded Portugal, but the House of Braganza avoided capture by escaping to Brazil . Napoleon captured King Ferdinand VII of Spain, and appointed his own brother instead. This appointment provoked popular resistance, which created Juntas to rule in the name of the captured king. Many cities in the Spanish colonies, however, considered themselves equally authorized to appoint local Juntas like those of Spain. This began

9490-588: The United Kingdom. The newly independent nations began a process of fragmentation, with several civil and international wars. However, it was not as strong as in Central America. Some countries created from provinces of larger countries stayed as such up to modern times (such as Paraguay or Uruguay), while others were reconquered and reincorporated into their former countries (such as the Republic of Entre Ríos and

9620-530: The bathypelagic anglerfishes , and the deep-water benthic rattails . Ray finned species, with spiny fins, are rare among deep-sea fishes, which suggests that deep-sea fish are ancient and so well adapted to their environment that invasions by more modern fishes have been unsuccessful. The few ray fins that do exist are mainly in the Beryciformes and Lampriformes , which are also ancient forms. Most deep-sea pelagic fishes belong to their own orders, suggesting

9750-516: The behaviour of mesopelagic fish. Mesopelagic fish are often highly mobile, whereas bathypelagic fish are almost all lie-in-wait predators, normally expending little energy in movement. The dominant bathypelagic fishes are small bristlemouth and anglerfish ; fangtooth , viperfish , daggertooth and barracudina are also common. These fishes are small, many about 10 centimetres (3.9 in) long, and not many longer than 25 centimetres (9.8 in). They spend most of their time waiting patiently in

9880-547: The birds prepare to emerge from a cave at dusk. The oilbird ranges from Guyana and the island of Trinidad to Venezuela , Colombia , Ecuador , Peru , Bolivia and Brazil . They range from sea-level to 3,400 m (11,200 ft). The species has highly specific habitat requirements, needing both caves to breed in and roost in frequently, and forest containing fruiting trees. Where suitable caves are absent, oilbirds will roost and breed in narrow gorges and grottos with suitable rock shelves. One such colony in Ecuador held

10010-437: The coast, helping establish fish as a primary source of food. Irrigation systems were also developed at this time, which aided in the rise of an agrarian society . South American cultures began domesticating llamas , vicuñas , guanacos , and alpacas in the highlands of the Andes circa 3500 BC. Besides their use as sources of meat and wool, these animals were used for transportation of goods. The rise of plant growing and

10140-433: The colour and intensity of light from above so that no shadow is cast. This tactic is known as counter-illumination. The lifecycle of deep-sea fish can be exclusively deep-water, although some species are born in shallower water and sink upon maturation. Regardless of the depth where eggs and larvae reside, they are typically pelagic. This planktonic — drifting — lifestyle requires neutral buoyancy. In order to maintain this,

10270-461: The concentration in producing one, or few, major export commodities has often hindered the development and diversification of its economies. The fluctuation in the price of commodities in international markets has led historically to major highs and lows, booms and busts, in the economies of South American states, often causing political instability. This has led for calls to diversify production and increase trade within South America itself. Brazil

10400-535: The conflict. The independence of South America was secured by Simón Bolívar (Venezuela) and José de San Martín (Argentina), the two most important Libertadores . Bolívar led a great uprising in the north, then led his army south towards Lima , the capital of the Viceroyalty of Peru . Meanwhile, San Martín led an army across the Andes Mountains, along with Chilean expatriates, and liberated Chile. He organized

10530-617: The current Humboldt and Falklands . The equatorial current of the South Atlantic strikes the coast of the Northeast and there is divided into two others: the current of Brazil and a coastal current that flows to the northwest towards the Antilles , where there it moves towards northeast course thus forming the most Important and famous ocean current in the world, the Gulf Stream . South America

10660-617: The dark. Bioluminescent organisms are capable of producing light biologically through the agitation of molecules of luciferin, which then produce light. This process must be done in the presence of oxygen. These organisms are common in the mesopelagic region and below (200 metres (656 ft) and below). More than 50% of deep-sea fish, as well as some species of shrimp and squid, are capable of bioluminescence. About 80% of these organisms have photophores – light producing glandular cells that contain luminous bacteria bordered by dark colourings. Some of these photophores contain lenses, much like those in

10790-482: The deep-sea by vertebrates may have occurred, although no fossil evidence of this is known. The earliest known records of deep-sea fish are trace fossils of feeding and swimming behavior attributed to unidentified neoteleosts (referable to the ichnogenera Piscichnus and Undichna ), from the Early Cretaceous (130 million-year-old) Palombini Shale of Italy , which is thought to have been deposited in

10920-419: The depths for safety during the day. These vertical migrations often occur over large vertical distances, and are undertaken with the assistance of a swim bladder . The swim bladder is inflated when the fish wants to move up, and, given the high pressures in the messoplegic zone, this requires significant energy. As the fish ascends, the pressure in the swim bladder must adjust to prevent it from bursting. When

11050-573: The eggs and larvae often contain oil droplets in their plasma. When these organisms are in their fully matured state they need other adaptations to maintain their positions in the water column. In general, water's density causes upthrust — the aspect of buoyancy that makes organisms float. To counteract this, the density of an organism must be greater than that of the surrounding water. Most animal tissues are denser than water, so they must find an equilibrium to make them float. Many organisms develop swim bladders (gas cavities) to stay afloat, but because of

11180-533: The end of the Pleistocene around 11,000 years ago as part of the Quaternary extinction event , among the highest of any continent, with the casualties including saber-toothed cats , ground sloths , glyptodonts , gomphotheres , the equines Hippidion and Equus neogeus , and all remaining South American native ungulates . South America is thought to have been first inhabited by humans when people were crossing

11310-736: The exception of hydrothermal vent ecosystems that can exceed 350 °C, or 662 °F), low oxygen levels, and pressures between 20 and 1000 atm (between 2 and 100 MPa ). It has been speculated that deep-sea ecosystems may have been inhospitable to vertebrate life prior to an increased influx of nutrients into the ocean during the Late Jurassic and Early Cretaceous following the rise of angiosperms on land, which led to an increase in abyssal invertebrate life, allowing fish to in turn colonize these ecosystems. However, some modern deep-sea fish, such as holocephalians , are descendants of much older lineages, indicating that much earlier colonizations of

11440-406: The expense of lateral vision, and allows the predator to pick out squid , cuttlefish , and smaller fish that are silhouetted against the gloom above them. Mesopelagic fish usually lack defensive spines, and use colour to camouflage themselves from other fish. Ambush predators are dark, black or red. Since the longer, red, wavelengths of light do not reach the deep sea, red effectively functions

11570-514: The eyes of humans, which can intensify or lessen the emanation of light. The ability to produce light only requires 1% of the organism's energy and has many purposes: It is used to search for food and attract prey, like the anglerfish; claim territory through patrol; communicate and find a mate, and distract or temporarily blind predators to escape. Also, in the mesopelagic where some light still penetrates, some organisms camouflage themselves from predators below them by illuminating their bellies to match

11700-531: The fact that in the past chicks were captured and boiled down in order to make oil. The fossil record of the family suggests that they were once more widely distributed around the globe. The first fossil oilbird was described by Storrs Olson in 1987 from a fossil found in the Green River Formation in Wyoming. The species, Prefica nivea , was probably not adapted to hovering flight or living in caves, unlike

11830-503: The female is ready to spawn, she has a mate immediately available. Many forms other than fish live in the bathypelagic zone, such as squid, large whales, octopuses, sponges, brachiopods , sea stars, and echinoids , but this zone is difficult for fish to live in. As a fish moves deeper into the sea, the weight of the water overhead exerts increasing hydrostatic pressure on the fish. This increased pressure amounts to about one atm (0.1 MPa) for every 10 m (32.8 ft)in depth. For

11960-454: The few birds known to supplement sight by echolocation in sufficiently poor light conditions, using a series of sharp audible clicks for this purpose. The only other birds known to do this are some species of swift . [REDACTED] In addition to clicks used for echolocation, oilbirds also produce a variety of harsh screams while in their caves. Entering a cave with a light especially provokes these raucous calls; they also may be heard as

12090-518: The fish wants to return to the depths, the swim bladder is deflated. Some mesopelagic fishes make daily migrations through the thermocline , where the temperature changes between 50 °F (10 °C) and 69 °F (20 °C), thus displaying considerable tolerances for temperature change. These fish have muscular bodies, ossified bones, scales, well developed gills and central nervous systems, and large hearts and kidneys. Mesopelagic plankton feeders have small mouths with fine gill rakers , while

12220-650: The great city of Cusco , the Inca civilization dominated the Andes region from 1438 to 1533. Known as Tawantin suyu , and "the land of the four regions", in Quechua , the Inca Empire was highly distinct and developed. Inca rule extended to nearly a hundred linguistic or ethnic communities, some nine to fourteen million people connected by a 25,000 kilometer road system . Cities were built with precise, unmatched stonework, constructed over many levels of mountain terrain. Terrace farming

12350-680: The high pressure of their environment, deep-sea fishes usually do not have this organ. Instead they exhibit structures similar to hydrofoils in order to provide hydrodynamic lift. It has also been found that the deeper a fish lives, the more jelly-like its flesh and the more minimal its bone structure. They reduce their tissue density through high fat content, reduction of skeletal weight — accomplished through reductions of size, thickness and mineral content — and water accumulation makes them slower and less agile than surface fish. The body shapes of deep-sea fish are generally better adapted for periodic bursts of swimming rather than constant swimming. Due to

12480-417: The island is geopolitically a part of Africa. All of the world's major climate zones are present in South America. The distribution of the average temperatures in the region presents a constant regularity from the 30° of latitude south , when the isotherms tend, more and more, to be confused with the degrees of latitude. In temperate latitudes, winters and summers are milder than in North America. This

12610-653: The islands of Trinidad and Tobago ( Trinidad Island and Tobago Island etc.), the State of Nueva Esparta , and the Federal Dependencies of Venezuela sit on the northern portion of the South American continental shelf and are sometimes considered parts of the continent. Geopolitically, all the island countries and territories in the Caribbean have generally been grouped as a subregion of North America instead. By contrast, Aves Island (administered by Venezuela ) and

12740-526: The land outside Europe should be an exclusive duopoly between the two countries. The treaty established an imaginary line along a north–south meridian 370 leagues west of the Cape Verde Islands , roughly 46° 37' W. In terms of the treaty, all land to the west of the line (known to comprise most of the South American soil) would belong to Spain, and all land to the east, to Portugal. As accurate measurements of longitude were impossible at that time,

12870-476: The line was not strictly enforced, resulting in a Portuguese expansion of Brazil across the meridian. Beginning in the 1530s, the people and natural resources of South America were repeatedly exploited by foreign conquistadors , first from Spain and later from Portugal. These competing colonial nations claimed the land and resources as their own and divided it into colonies. European infectious diseases ( smallpox , influenza , measles , and typhus ) – to which

13000-453: The mid-17th century. It became a Dutch colony in 1667. The indigenous peoples of the Americas in various European colonies were forced to work in European plantations and mines; along with enslaved Africans who were also introduced in the proceeding centuries via the slave trade . European colonists were heavily dependent on indigenous labor during the initial phases of settlement to maintain

13130-544: The most widely distributed, populous, and diverse of all vertebrates , playing an important ecological role as prey for larger organisms. With an estimated global biomass of 550–660 million metric tons , several times the entire world fisheries catch, lanternfish also account for much of the biomass responsible for the deep scattering layer of the world's oceans. In the Southern Ocean , Myctophids provide an alternative food resource to krill for predators such as squid and

13260-413: The observation that actin from the muscle fibers of deep-sea fish are extremely heat-resistant; an observation similar to what is found in lizards. These proteins are structurally strengthened by modification of the bonds in the tertiary structure of the protein which also happens to induce high levels of thermal stability. Proteins are structurally strengthened to resist pressure by modification of bonds in

13390-462: The ocean floor. However, most organic components of marine snow are consumed by microbes , zooplankton and other filter-feeding animals within the first 1,000 metres (3,281 ft) of their journey, that is, within the epipelagic zone. In this way marine snow may be considered the foundation of deep-sea mesopelagic and benthic ecosystems : As sunlight cannot reach them, deep-sea organisms rely heavily on marine snow as an energy source. Since there

13520-543: The ocean. These zones make up about 75% of the inhabitable ocean space. The epipelagic zone (0–200 metres (0–656 ft) deep) is the area where light penetrates the water and photosynthesis occurs. This is also known as the photic zone. Because this typically extends only a few hundred meters below the water, the deep sea, about 90% of the ocean volume, is in darkness. The deep sea is also an extremely hostile environment, with temperatures that rarely exceed 3 °C (37 °F) and fall as low as −1.8 °C (29 °F) (with

13650-584: The oilbird. Some of the same families and genera of plants the present day oilbird feeds on have been found in the Green River Formation, suggesting that prehistoric species may have eaten the same fruit and spread the same seeds. Another species from the Upper Eocene has been discovered in France. This is a large, slim bird at 40–49 cm (16–19 in), with a wing span of 95 cm (37 in). It has

13780-439: The only nocturnal flying fruit-eating birds in the world (the kākāpō , also nocturnal, is flightless). They forage at night, with specially adapted eyesight. However, they navigate by echolocation in the same way as bats , one of the few birds to do so. They produce a high-pitched clicking sound of around 2 kHz that is audible to humans. Oilbirds are related to the nightjars and have sometimes been placed with these in

13910-508: The other nights roosting in trees. The scientists responsible for the discovery also found that birds roosting in caves were highly active through the night, whereas birds roosting in the forest were far less active. They hypothesised that each environment carried costs; birds roosting in the forest were more vulnerable to predators and birds roosting in caves expended considerable energy competing with rivals and defending nesting and roosting ledges. Oilbirds are colonial cave nesters. The nest

14040-458: The pitch black of the deep ocean. The deep-sea angler fish in particular has a long fishing-rod-like adaptation protruding from its face, on the end of which is a bioluminescent piece of skin that wriggles like a worm to lure its prey. Some must consume other fish that are the same size or larger than them and they need adaptations to help digest them efficiently. Great sharp teeth, hinged jaws, disproportionately large mouths, and expandable bodies are

14170-508: The poor level of photosynthetic light reaching deep-sea environments, most fish need to rely on organic matter sinking from higher levels, or, in rare cases, hydrothermal vents for nutrients. This makes the deep-sea much poorer in productivity than shallower regions. Also, animals in the pelagic environment are sparse and food doesn't come along frequently. Because of this, organisms need adaptations that allow them to survive. Some have long feelers to help them locate prey or attract mates in

14300-450: The reactions usually involve volume increases. Species that can tolerate these depths have evolved changes in their protein structure and reaction criteria to withstand pressure, in order to perform reactions in these conditions. In high pressure environments, bilayer cellular membranes experience a loss of fluidity. Deep-sea cellular membranes favor phospholipid bilayers with a higher proportion of unsaturated fatty acids , which induce

14430-683: The records from the Palombini Shale represent the earliest records of deep-sea bony fish, formations that preserve deepwater shark fossils are also known from later in the Cretaceous. These include the Northumberland Formation of Canada and similarly aged deposits in Angola, both of which preserve fossils of taxa such as hexanchids , chlamydoselachids , and catsharks , which are known from deepwater habitats today but rare in other formations of

14560-419: The reduced fluidity of their membranes because molecules are squeezed together. Fluidity in cell membranes increases efficiency of biological functions, most importantly the production of proteins, so organisms have adapted to this circumstance by increasing the proportion of unsaturated fatty acids in the lipids of the cell membranes. In addition to differences in internal pressure, these organisms have developed

14690-423: The same as black. Migratory forms use countershaded silvery colours. On their bellies, they often display photophores producing low grade light. For a predator from below, looking upwards, this bioluminescence camouflages the silhouette of the fish. However, some of these predators have yellow lenses that filter the (red deficient) ambient light, leaving the bioluminescence visible. The brownsnout spookfish ,

14820-424: The sonar. These organisms migrate up into shallower water at dusk to feed on plankton. The layer is deeper when the moon is out, and can become shallower when clouds pass over the moon. This phenomenon has come to be known as the deep scattering layer . Most mesopelagic fish make daily vertical migrations , moving at night into the epipelagic zone, often following similar migrations of zooplankton, and returning to

14950-421: The subsequent appearance of permanent human settlements allowed for the multiple and overlapping beginnings of civilizations in South America. One of the earliest known South American civilizations was Caral–Supe , on the central Peruvian coast. Though a pre-ceramic culture, the monumental architecture of Caral–Supe created one of the first cities of the world, generally dated to around 3500 BC, at Huaricanga in

15080-411: The subsistence economy, and natives were often captured by expeditions. The importation of African slaves began midway through the 16th century, but the enslavement of indigenous peoples continued well into the 17th and 18th centuries. The Atlantic slave trade brought enslaved Africans primarily to South American colonies, beginning with the Portuguese since 1502. The main destinations of this phase were

15210-734: The surface. The fish of the deep-sea have evolved various adaptations to survive in this region. Since many of these fish live in regions where there is no natural illumination , they cannot rely solely on their eyesight for locating prey and mates and avoiding predators; deep-sea fish have evolved appropriately to the extreme sub-photic region in which they live. Many of these organisms are blind and rely on their other senses, such as sensitivities to changes in local pressure and smell, to catch their food and avoid being caught. Those that aren't blind have large and sensitive eyes that can use bioluminescent light. These eyes can be as much as 100 times more sensitive to light than human eyes. Rhodopsin (Rh1)

15340-423: The tertiary structure. Therefore, high levels of hydrostatic pressure, similar to high body temperatures of thermophilic desert reptiles, favor rigid protein structures. Na+/K+ -ATPase is a lipoprotein enzyme that plays a prominent role in osmoregulation and is heavily influenced by hydrostatic pressure. The inhibition of Na+/K+ -ATPase is due to increased compression due to pressure. The rate-limiting step of

15470-662: The time. Paleogene formations with fossil deep-sea shark teeth are known from New Zealand for the middle Paleocene , and formations in Denmark, France, Austria, and Morocco during the Eocene. The Paratethys Sea still supported deepwater sharks and rays into the Miocene, which are preserved in formations in Hungary. During the Paleogene, some prominent formations that preserve well-articulated specimens of deep-sea bony fish are known. These include

15600-484: The upper epipelagic zone, but they wither or fill with fat when the fish move down to their adult habitat. A couple of known exceptions are the cusk-eel ( Holcomycteronus profundissimus ), retrieved from 7160 meters deep, and the rough abyssal grenadier ( Coryphaenoides yaquinae ), found at 7259 meters depth. These species still have functional swim bladders, which allows them to maintain high bone density and strong jaws. The most important sensory systems are usually

15730-485: The vertical migrations of prey organisms in the deep scattering layer . Below the mesopelagic zone it is pitch dark. This is the midnight (or bathypelagic zone ), extending from 1,000 metres (3,281 ft) to the bottom deep-water benthic zone . If the water is exceptionally deep, the pelagic zone below 4,000 metres (13,123 ft) is sometimes called the lower midnight (or abyssopelagic zone ). Temperatures in this zone range from 1 to 4 °C (34 to 39 °F) and it

15860-421: The volume of the organism to some degree. Most fish that have evolved in this harsh environment are not capable of surviving in laboratory conditions, and attempts to keep them in captivity have led to their deaths. Deep-sea organisms contain gas-filled spaces (vacuoles). Gas is compressed under high pressure and expands under low pressure. Because of this, these organisms have been known to blow up if they come to

15990-494: The water column for prey to appear or to be lured by their phosphors. What little energy is available in the bathypelagic zone filters from above in the form of detritus, faecal material, and the occasional invertebrate or mesopelagic fish. About 20 per cent of the food that has its origins in the epipelagic zone falls down to the mesopelagic zone, but only about 5 per cent filters down to the bathypelagic zone. Bathypelagic fish are sedentary, adapted to outputting minimum energy in

16120-789: The water with little expenditure of energy. Despite their ferocious appearance, these forms are mostly miniature fish with weak muscles, and are too small to represent any threat to humans. An exception to the generally small size of bathypelagic fish is the Yokozuna slickhead ( Narcetes shonanmaruae ), described in 2021, which is the largest known entirely bathypelagic bony fish at over 2.5 metres (8.2 ft) in length. The swim bladders of deep-sea fish are either absent or scarcely operational, and bathypelagic fish do not normally undertake vertical migrations. Filling bladders at such great pressures incurs huge energy costs. Some deep-sea fishes have swim bladders which function while they are young and inhabit

16250-568: The western European architectural style to the continent, and helped to improve infrastructures like bridges, roads, and the sewer system of the cities they discovered or conquered. They also significantly increased economic and trade relations, not just between the old and new world but between the different South American regions and peoples. Finally, with the expansion of the Portuguese and Spanish languages, many cultures that were previously separated became united through that of Latin American. Guyana

16380-424: The wings have deep wingtip slotting, like New World vultures , to reduce the stalling speed, and the wings have a low aspect ratio and low wing-loading, all to make the oilbird capable of flying at low speeds. The eyes of oilbirds are highly adapted to nocturnal foraging. The eyes are small, but the pupils are relatively large, allowing the highest light-gathering capacity of any bird ( f-number of 1.07). The retina

16510-465: Was Chile in 1823, Uruguay in 1830, Bolivia in 1831, Guyana in 1833, Colombia and Ecuador in 1851, Argentina in 1853, Peru and Venezuela in 1854, Suriname in 1863, Paraguay in 1869, and in 1888 Brazil was the last South American nation and the last country in western world to abolish slavery. The European Peninsular War (1807–14), a theater of the Napoleonic Wars , changed the political situation of

16640-515: Was Venezuela's first national monument and is the centerpiece of a national park; according to some estimates there may be 15,000 or more birds living there. Colombia also has a national park named after its " Cueva de los Guácharos ", near the southern border with Ecuador. Oilbirds have been reported in various other places along the Andean mountain chain, including near Ecuador's Cueva de los Tayos and in Brazil : they are known to dwell as far south as

16770-614: Was a useful form of agriculture. The Mapuche in Central and Southern Chile resisted the European and Chilean settlers, waging the Arauco War for more than 300 years. In 1494, Portugal and Spain, the two great maritime European powers of that time, on the expectation of new lands being discovered in the west, signed the Treaty of Tordesillas , by which they agreed, with the support of the Pope, that all

16900-549: Was initially colonized by the Dutch before coming under British control , though there was a brief period during the Napoleonic Wars when it was occupied by the French . The region was initially partitioned between the Dutch, French and British before fully coming under the control of Britain. Suriname was first explored by the Spanish in the 16th century and then settled by the English in

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