87-511: Alvarezsauroidea is a group of small maniraptoran dinosaurs . Alvarezsauroidea, Alvarezsauridae , and Alvarezsauria are named for the historian Gregorio Álvarez , not the more familiar physicist Luis Alvarez , or his son geologist Walter Alvarez who jointly proposed that the Cretaceous–Paleogene extinction event was caused by an impact event . The group was first formally proposed by Choiniere and colleagues in 2010, to contain
174-608: A dromaeosaurid , was too heavy to fly but still had wings with feathers required for flying, which suggests its ancestors had the ability for aerial locomotion. Other groups, like the Oviraptorosauria who had a tail with a tail fan of feathers with caudal anatomy resembling a pygostyle , are not known to have been capable of flight, but some scientists, such as Gregory S. Paul , have suggested that they could be descended from ancestors which flew. Paul has gone as far as to propose that Therizinosauria , Alvarezsauroidea , and
261-407: A trochanteric crest . An elongated, backwards-pointing pubic bone is present in therizinosauroids, dromaeosaurids, avialans, and the basal troodontid Sinovenator , which suggests that the propubic condition in advanced troodontids and oviraptorosaurs is a reversal. Turner et al. (2007) named seven synapomorphies that diagnose Maniraptora. Modern pennaceous feathers and remiges are known in
348-493: A 2001 paper. Their proposed definition for the group was "the clade stemming from the first panavian with ... remiges and rectrices , that is, enlarged, stiff-shafted, closed-vaned (= barbules bearing hooked distal pennulae), pennaceous feathers arising from the distal forelimbs and tail". Ancestral morphology relating to pennaceous feathers suggests that basal species of Pennaraptora were capable of scansorial locomotion and gliding, and further evolution of said adaptation within
435-500: A feathered bird-like predator) is a clade within Maniraptora, defined as the most recent common ancestor of Oviraptor philoceratops , Deinonychus antirrhopus , and Passer domesticus (the house sparrow), and all descendants thereof, by Foth et al. , 2014. The clade "Aviremigia" was conditionally proposed along with several other apomorphy -based clades relating to birds by Jacques Gauthier and Kevin de Queiroz in
522-698: 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
609-459: 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
696-503: A long, backwards-pointed pubis and short ischia were present in Scansoriopteryx , a scansoriopterygid. The authors considered it to be more primitive than true theropods, and hypothesized that maniraptorans may have branched off from theropods at a very early point, or may even have descended from pre-theropod dinosaurs. Zhang et al. , in describing the closely related or conspecific specimen Epidendrosaurus (now considered
783-450: A number of discoveries made during the first decade of the 21st century, as well as re-evaluation of older evidence, began to suggest that maniraptorans were a primarily omnivorous group, including a number of sub-groups that ate mainly plants, insects, or other food sources besides meat. Additionally, phylogenetic studies of maniraptoran relationships began to more consistently show that herbivorous or omnivorous groups were spread throughout
870-682: 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
957-481: 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
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#17327837607891044-689: 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
1131-482: A synonym of Scansoriopteryx ), did not report any of the primitive traits mentioned by Czerkas and Yuan, but did find that the shoulder blade of Epidendrosaurus appeared primitive. Despite this, they placed Epidendrosaurus firmly within Maniraptora due to a number of synapomorphies. Scientists traditionally assumed that maniraptorans were ancestrally hypercarnivorous , that is, that most non-avialan species primarily ate and hunted only other vertebrates . However,
1218-486: Is a striking evolutionary phenomenon that is clearly exemplified in theropod dinosaurs. The enlargement of the manual digit II in alvarezsauroids and the concurrent reduction of the lateral digits, created one functional medial digit and two very small, and presumably vestigial, lateral digits. These morphological changes have been interpreted as adaptations for digging. One possible interpretation suggests that alvarezsauroids fed on insects, using their hands to search beyond
1305-668: Is based on differences in their morphology , especially in their hand morphology. The first fossil alvarezsauroids were recognized in the 1990s. Since then, the number of specimens found has dramatically increased. Most of the recent alvarezsauroids are found in China, but they are also known from the Americas and Europe. They existed from the Late Jurassic to the Late Cretaceous . The basalmost and oldest alvarezsauroid of
1392-526: 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
1479-460: 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
1566-407: Is consistent with faunal interchanges. On the other hand, some theropod groups are inconsistent with this hypothesis . Xu et al . (2013) used event−based tree−fitting to perform a quantitative analysis of alvarezsauroid biogeography. Their results showed an absence of statistical support for previous biogeographic hypotheses that favour pure vicariance or pure dispersal scenarios as explanations for
1653-605: 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
1740-614: 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
1827-480: 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
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#17327837607891914-582: 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 ),
2001-519: 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
2088-586: 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
2175-820: 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,
2262-717: 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,
2349-578: 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,
2436-1030: 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
2523-470: 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
2610-472: 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
2697-715: 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
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2784-803: 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 :
2871-599: 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
2958-891: The Ornithomimiformes . The cladogram below is based on Choniere et al . (2010). † Haplocheirus † Alvarezsaurus † Achillesaurus † Patagonykus † Parvicursor † Shuvuuia † Mononykus † Albertonykus At first, alvarezsauroids were thought to have been originated in South America . However, the discovery of Haplocheirus , and its basal phylogenetic position, as well as its early temporal position, suggests they derived in Asia rather than South America . Xu et al . (2011) suggested that at least three dispersal events of alvarezsauroids took place; one from Asia to Gondwana , one from Gondwana to Asia, and one from Asia to North America . This hypothesis
3045-547: 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
3132-738: 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
3219-665: 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,
3306-613: 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
3393-602: The birds and the non-avian dinosaurs that were more closely related to them than to Ornithomimus velox . It contains the major subgroups Avialae , Dromaeosauridae , Troodontidae , Oviraptorosauria , and Therizinosauria . Ornitholestes and the Alvarezsauroidea are also often included. Together with the next closest sister group, the Ornithomimosauria , Maniraptora comprises the more inclusive clade Maniraptoriformes . Maniraptorans first appear in
3480-712: 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,
3567-520: The scansoriopterygids , Pedopenna , and Yixianosaurus . In 1993, Perle and colleagues coined the name Metornithes to include alvarezsaurids and modern birds, which the researchers believed were members of the Avialae. This group was defined as a clade by Luis Chiappe in 1995 as the last common ancestor of Mononykus and modern birds, and all its descendants. Pennaraptora (Latin penna "bird feather" + raptor "thief", from rapere "snatch";
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3654-411: The "primitive" forward-pointing hip seen in advanced troodontids and oviraptorosaurs is an evolutionary reversal, and that these groups evolved from ancestors with backward-pointing hips. Holtz and Osmólska (2004) diagnosed the clade Maniraptora based on the following characters: reduced or absent olecranon process of the ulna , greater trochanter and cranial trochanter of the femur fused into
3741-755: 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
3828-692: 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
3915-748: 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
4002-635: The Chinese alvarezsaurs is from the Shishugou Formation in Xinjiang (earliest Late Jurassic). Additionally, two derived members of the derived alvarezsaur group Parvicursorinae are known from the Inner Mongolia and Henan (Late Cretaceous). The size of the derived members of Alvarezsauroidea range between 0.5 and 2 m (1 ft 8 in and 6 ft 7 in), but some members may have been larger. Haplocheirus , for example,
4089-461: The Maniraptora, rather than representing a single side-branch as previously thought. This led scientists such as Lindsay Zanno to conclude that the ancestral maniraptoran must have been omnivorous, giving rise to several purely herbivorous groups (such as the therizinosaurs, primitive oviraptorosaurs, and some avialans) and that, among non-avians, only one group reverted to pure carnivores (the dromaeosaurids). Most other groups fell somewhere in between
4176-447: 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 ,
4263-830: 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
4350-483: 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
4437-446: The Turonian-age Bissekty Formation (some of which were named Dzharaonyx in 2022) of Uzbekistan and Bannykus , Tugulusaurus , and Xiyunykus from the Early Cretaceous of China. The differences in the morphology of the hand of basic Alvarezsauroidea and the derived members are characterized by digit reduction. In the evolution of theropod dinosaurs, modifications of the hand were typical. The digital reduction, for instance,
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#17327837607894524-423: 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
4611-418: The advanced maniraptoran group Aviremigia . More primitive maniraptorans, such as therizinosaurs (specifically Beipiaosaurus ), preserve a combination of simple downy filaments and unique elongated quills. Simple feathers are known from more primitive coelurosaurs such as Sinosauropteryx prima , and possibly from even more distantly related species such as the ornithischian Tianyulong confuciusi and
4698-479: The clade would eventually give rise to the origin of flight in avian species. The following cladogram follows the results of a phylogenetic study by Cau (2020). † Alvarezsauroidea [REDACTED] † Therizinosauridae [REDACTED] † Oviraptorosauria [REDACTED] † Dromaeosauridae [REDACTED] † Troodontidae [REDACTED] Avialae [REDACTED] In 2002, Czerkas and Yuan reported that some maniraptoran traits, such as
4785-437: 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
4872-461: 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
4959-424: 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
5046-405: 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
5133-403: The distributions of alvarezsauroids across South America, North America and Asia. They instead found that statistically significant biogeographic reconstructions suggest a dominant role for sympatric events (“within area” ones), combined with a mix of vicariance, dispersal and regional extinction. The Asian origin of alvarezsauroids is also bolstered by the discovery of alvarezsaurid specimens from
5220-439: The earlier branch-based definition. The branch-based definition usually includes the major groups Dromaeosauridae , Troodontidae , Oviraptorosauria , Therizinosauria , and Avialae . Other taxa often found to be maniraptorans include the alvarezsaurs and Ornitholestes . Several taxa have been assigned to the Maniraptora more definitively, though their exact placement within the group remains uncertain. These forms include
5307-427: 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
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#17327837607895394-423: The family Alvarezsauridae and non-alvarezsaurid alvarezsauroids, such as Haplocheirus , which is the basalmost of the Alvarezsauroidea (from the Late Jurassic , Asia ). The discovery of Haplocheirus extended the stratigraphic evidence for the group Alvarezsauroidea about 63 million years further in the past. The division of Alvarezsauroidea into the Alvarezsauridae and the non-alvarezsaurid alvarezsauroids
5481-431: The first discovered species Mononykus and Shuvuuia . This shows that bird-like characteristics were developed multiple times within the Maniraptora . Furthermore, the Alvarezsauroidea had simplified homogenous dentition, convergent with that of some extant insectivorous mammals . More recently, they have been placed within the Coelurosauria basal to the Maniraptora or as a sister taxa of Ornithomimosauria within
5568-513: The flying pterosaurs . Thus it appears as if some form of feathers or down-like integument would have been present in all maniraptorans, at least when they were young. Maniraptora is the only dinosaur group known to include flying members, though how far back in this lineage flight extends is controversial. Powered and/or gliding flight is believed to have been present in some types of non-avialan paravians, including dromaeosaurids, such as Rahonavis and Microraptor . Zhenyuanlong suni ,
5655-419: The fossil record during the Jurassic Period (see Eshanosaurus ), and survive today as living birds. Maniraptorans are characterized by long arms and three-fingered hands (though reduced or fused in some lineages), as well as a "half-moon shaped" (semi- lunate ) bone in the wrist ( carpus ). In 2004, Tom Holtz and Halszka Osmólska pointed out six other maniraptoran characters relating to specific details of
5742-502: 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
5829-420: The group Avialae and considered to be flightless birds, because they share many morphological characteristics with them, such as a loosely sutured skull, a keeled sternum , fused wrist elements, and a posteriorly directed pubis . But this association was reevaluated after the discovery of the primitive forms like Haplocheirus , Patagonykus and Alvarezsaurus , which do not show all bird-like features as
5916-417: 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
6003-487: 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
6090-466: 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,
6177-476: 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
6264-458: 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
6351-439: The name Maniraptora, which means "hand snatchers" in relation to their 'seizing hands'). In 1994, Thomas R. Holtz attempted to define the group based on the characteristics of the hand and wrist alone (an apomorphy-based definition), and included the long, thin fingers, bowed, wing-like forearm bones, and half-moon shaped wrist bone as key characters. Most subsequent studies have not followed this definition, however, preferring
6438-413: The non-maniraptoran group Ornithomimosauria also descended from flying ancestors. The Maniraptora was originally named by Jacques Gauthier in 1986, for a branch-based clade defined as all dinosaurs closer to modern birds than to the ornithomimids . Gauthier noted that this group could be easily characterized by their long forelimbs and hands, which he interpreted as adaptations for grasping (hence
6525-555: The one functional ovary in birds, and were thus limited in the numbers of eggs each individual could produce. [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] [REDACTED] South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere , with a considerably smaller portion in
6612-421: The other side possesses recurved serrated teeth. The dentition of Haplocheirus and their basal phylogenetic position, suggest that carnivory was the primitive condition for the clade. Furthermore, Haplocheirus possesses more teeth on the maxilla than other alvarezsauroids. [REDACTED] [REDACTED] Maniraptora Maniraptora is a clade of coelurosaurian dinosaurs which includes
6699-444: The skeleton. Unlike most other saurischian dinosaurs, which have pubic bones that point forward, several groups of maniraptorans have an ornithischian -like backwards-pointing hip bone. A backward-pointing hip characterizes the therizinosaurs , dromaeosaurids , avialans , and some primitive troodontids . The fact that the backward-pointing hip is present in so many diverse maniraptoran groups has led most scientists to conclude that
6786-421: 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
6873-411: 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
6960-424: The tree bark. This interpretation is consistent with their long, elongate snout and small teeth. Another interpretation suggests that they used their claws to break into ant and termite colonies, though the arm anatomy of an alvarezsaurid would require the animal to lie on its chest against a termite nest. In contrast to the digit reduction of the hand of derived alvarezsauroid to a claw used for digging, Haplocheirus
7047-644: The two extremes, with alvarezsaurids and some avialans being insectivorous, and with advanced oviraptorosaurs and troodontids being omnivorous. A 2023 study analyzing fossil eggshells assigned to Troodon with clumped isotope thermometry found that Troodon , and likely other non-avian maniraptorans, had a slowed calcification of eggs akin to that of most reptiles. This contrasts with the rapid calcification of eggs found in modern birds, indicating that most maniraptorans aside from birds retained this basal trait. This would also indicate that most non-avian maniraptorans possessed two functional ovaries , contrasting with
7134-573: 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
7221-472: 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
7308-633: 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
7395-562: 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
7482-402: Was still able to grab things. However, Haplocheirus already shows the enlargement of the second manual digit. Important data on the evolution of the alvarezsauroid hand is also provided by the basal parvicursorine Linhenykus . Another difference between Alvarezsauridae and Haplocheirus is the dentition. While alvarezsauroids show a simplified homogenous dentition, Haplocheirus on
7569-553: Was the largest member of the Alvarezsauroidea. Because of the size of Haplocheirus and its basal phylogenetic position, a pattern of miniaturization for the Alvarezsauroidea is suggested. Miniaturizations are very rare in dinosaurs, but convergently evolved in Paraves . The phylogenetic placement of Alvarezsauroidea is still unclear. At first, they were interpreted as a sister group of Avialae (birds) or nested within
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