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Late Miocene

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The Miocene ( / ˈ m aɪ . ə s iː n , - oʊ -/ MY -ə-seen, -⁠oh- ) is the first geological epoch of the Neogene Period and extends from about 23.03 to 5.333 million years ago (Ma). The Miocene was named by Scottish geologist Charles Lyell ; the name comes from the Greek words μείων ( meíōn , "less") and καινός ( kainós , "new") and means "less recent" because it has 18% fewer modern marine invertebrates than the Pliocene has. The Miocene followed the Oligocene and preceded the Pliocene.

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122-688: The Late Miocene (also known as Upper Miocene ) is a sub-epoch of the Miocene Epoch made up of two stages . The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma ( million years ago ) to 5.333 Ma. The gibbons (family Hylobatidae) and orangutans (genus Pongo ) are the first groups to split from the line leading to the hominins , including humans , then gorillas (genus Gorilla ), and finally chimpanzees and bonobos (genus Pan ). The splitting date between hominin and chimpanzee lineages

244-461: A complex calendric system , a tradition of ball playing , and a distinct architectural style , were diffused through the area. Villages began to become socially stratified and develop into chiefdoms , and large ceremonial centers were built, interconnected by a network of trade routes for the exchange of luxury goods, such as obsidian , jade , cacao , cinnabar , Spondylus shells, hematite , and ceramics. While Mesoamerican civilization knew of

366-542: A broader aridification trend. The EMCI ended 18 million years ago, giving way to the Middle Miocene Warm Interval (MMWI), the warmest part of which was the MMCO that began 16 million years ago. As the world transitioned into the MMCO, carbon dioxide concentrations varied between 300 and 500 ppm. Global annual mean surface temperature during the MMCO was about 18.4 °C. MMCO warmth was driven by

488-686: A cave in Oaxaca. Earlier maize samples have been documented at the Los Ladrones cave site in Panama , c. 5500 BCE. Slightly thereafter, semi- agrarian communities began to cultivate other crops throughout Mesoamerica. Maize was the most common domesticate, but the common bean, tepary bean, scarlet runner bean, jicama , tomato and squash all became common cultivates by 3500 BCE. At the same time, these communities exploited cotton , yucca , and agave for fibers and textile materials. By 2000 BCE, corn

610-529: A clade of large terrestrial predatory crocodyliformes distantly related to modern crocodilians, from which they likely diverged over 180 million years ago, are known from the Miocene of South America. The last Desmostylians thrived during this period before becoming the only extinct marine mammal order. The pinnipeds , which appeared near the end of the Oligocene, became more aquatic. A prominent genus

732-509: A cooler, drier climate. C 4 grasses, which are able to assimilate carbon dioxide and water more efficiently than C 3 grasses, expanded to become ecologically significant near the end of the Miocene between 6 and 7 million years ago, although they did not expand northward during the Late Miocene. The expansion of grasslands and radiations among terrestrial herbivores correlates to fluctuations in CO 2 . One study, however, has attributed

854-431: A cultural area based on a suite of interrelated cultural similarities brought about by millennia of inter- and intra-regional interaction (i.e., diffusion ). Mesoamerica is recognized as a near-prototypical cultural area. This term is now fully integrated into the standard terminology of precolumbian anthropological studies. Conversely, the sister terms Aridoamerica and Oasisamerica , which refer to northern Mexico and

976-486: A good analogue for future warmer climates caused by anthropogenic global warming , with this being especially true of the global climate during the Middle Miocene Climatic Optimum (MMCO), because the last time carbon dioxide levels were comparable to projected future atmospheric carbon dioxide levels resulting from anthropogenic climate change was during the MMCO. The Ross Sea margin of

1098-435: A good model for a "living fossil". Eucalyptus fossil leaves occur in the Miocene of New Zealand , where the genus is not native today, but have been introduced from Australia . Both marine and continental fauna were fairly modern, although marine mammals were less numerous. Only in isolated South America and Australia did widely divergent fauna exist. In Eurasia, genus richness shifted southward to lower latitudes from

1220-779: A low plateau that breaks up the Sierra Madre chain between the Sierra Madre del Sur to the north and the Sierra Madre de Chiapas to the south. At its highest point, the Isthmus is 224 m (735 ft) above mean sea level. This area also represents the shortest distance between the Gulf of Mexico and the Pacific Ocean in Mexico. The distance between the two coasts is roughly 200 km (120 mi). The northern side of

1342-598: A major expansion of Antarctic glaciers. This severed the connection between the Indian Ocean and the Mediterranean Sea and formed the present land connection between Afro-Arabia and Eurasia. The subsequent uplift of mountains in the western Mediterranean region and a global fall in sea levels combined to cause a temporary drying up of the Mediterranean Sea (known as the Messinian salinity crisis ) near

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1464-480: A major expansion of grass-grazer ecosystems . Herds of large, swift grazers were hunted by predators across broad sweeps of open grasslands , displacing desert, woodland, and browsers . The higher organic content and water retention of the deeper and richer grassland soils , with long-term burial of carbon in sediments, produced a carbon and water vapor sink. This, combined with higher surface albedo and lower evapotranspiration of grassland, contributed to

1586-717: A period commonly known as the Tikal Hiatus . The Late Classic period (beginning c. 600 CE until 909 CE) is characterized as a period of interregional competition and factionalization among the numerous regional polities in the Maya area. This largely resulted from the decrease in Tikal's socio-political and economic power at the beginning of the period. It was therefore during this time that other sites rose to regional prominence and were able to exert greater interregional influence, including Caracol, Copán , Palenque , and Calakmul (which

1708-772: A regionally important center during the Postclassic. The latter portion of the Postclassic is generally associated with the rise of the Mexica and the Aztec Empire . One of the more commonly known cultural groups in Mesoamerica, the Aztec politically dominated nearly all of central Mexico, the Gulf Coast, Mexico's southern Pacific Coast (Chiapas and into Guatemala), Oaxaca, and Guerrero . The Tarascans (also known as

1830-602: A significant drop in atmospheric carbon dioxide levels. Both continental and oceanic thermal gradients in mid-latitudes during the Early Miocene were very similar to those in the present. Global cooling caused the East Asian Summer Monsoon (EASM) to begin to take on its modern form during the Early Miocene. From 22.1 to 19.7 Ma, the Xining Basin experienced relative warmth and humidity amidst

1952-700: A significant local decline along the northeastern coast of Australia during the Tortonian, most likely due to warming seawater. Cetaceans attained their greatest diversity during the Miocene, with over 20 recognized genera of baleen whales in comparison to only six living genera. This diversification correlates with emergence of gigantic macro-predators such as megatoothed sharks and raptorial sperm whales . Prominent examples are O. megalodon and L. melvillei . Other notable large sharks were O. chubutensis , Isurus hastalis , and Hemipristis serra . Crocodilians also showed signs of diversification during

2074-484: A technological departure from previous construction techniques. Major Puuc sites include Uxmal , Sayil , Labna , Kabah , and Oxkintok . While generally concentrated within the area in and around the Puuc hills , the style has been documented as far away as at Chichen Itza to the east and Edzna to the south. Chichén Itzá was originally thought to have been a Postclassic site in the northern Maya lowlands. Research over

2196-651: A zone of low rainfall in the Late Miocene. The Indian Plate continued to collide with the Eurasian Plate , creating new mountain ranges and uplifting the Tibetan Plateau , resulting in the rain shadowing and aridification of the Asian interior. The Tian Shan experienced significant uplift in the Late Miocene, blocking westerlies from coming into the Tarim Basin and drying it as a result. At

2318-505: Is Pico de Orizaba , a dormant volcano located on the border of Puebla and Veracruz . Its peak elevation is 5,636 m (18,490 ft). The Sierra Madre mountains, which consist of several smaller ranges, run from northern Mesoamerica south through Costa Rica . The chain is historically volcanic . In central and southern Mexico, a portion of the Sierra Madre chain is known as the Eje Volcánico Transversal , or

2440-475: Is a list of some of the specialized resources traded from the various Mesoamerican sub-regions and environmental contexts: Mesoamerican architecture is the collective name given to urban, ceremonial and public structures built by pre-Columbian civilizations in Mesoamerica. Although very different in styles, all kinds of Mesoamerican architecture show some kind of interrelation, due to very significant cultural exchanges that occurred during thousands of years. Among

2562-631: Is another Classic-period polity that expanded and flourished during this period, but the Zapotec capital exerted less interregional influence than the other two sites. During the Early Classic, Teotihuacan participated in and perhaps dominated a far-reaching macro-regional interaction network. Architectural and artifact styles (talud-tablero, tripod slab-footed ceramic vessels) epitomized at Teotihuacan were mimicked and adopted at many distant settlements. Pachuca obsidian, whose trade and distribution

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2684-453: Is argued to have been economically controlled by Teotihuacan, is found throughout Mesoamerica. Tikal came to dominate much of the southern Maya lowlands politically, economically, and militarily during the Early Classic. An exchange network centered at Tikal distributed a variety of goods and commodities throughout southeast Mesoamerica, such as obsidian imported from central Mexico (e.g., Pachuca) and highland Guatemala (e.g., El Chayal , which

2806-718: Is located 70 km (43 mi) southeast of Mexico City. Other volcanoes of note include Tacana on the Mexico–Guatemala border, Tajumulco and Santamaría in Guatemala, Izalco in El Salvador, Arenal in Costa Rica, and Concepción and Maderas on Ometepe , which is an island formed by both volcanoes rising out of Lake Cocibolca in Nicaragua. One important topographic feature is the Isthmus of Tehuantepec ,

2928-453: Is marked by the rise and dominance of several polities. The traditional distinction between the Early and Late Classic is marked by their changing fortune and their ability to maintain regional primacy. Of paramount importance are Teotihuacán in central Mexico and Tikal in Guatemala; the Early Classic's temporal limits generally correlate to the main periods of these sites. Monte Albán in Oaxaca

3050-409: Is not rigid. The Maya area, for example, can be divided into two general groups: the lowlands and highlands. The lowlands are further divided into the southern and northern Maya lowlands. The southern Maya lowlands are generally regarded as encompassing northern Guatemala , southern Campeche and Quintana Roo in Mexico, and Belize . The northern lowlands cover the remainder of the northern portion of

3172-705: Is one notable difference between Mesoamerica and the cultures of the South American Andes. Other animals, including the duck , dogs , and turkey , were domesticated . Turkey was the first to be domesticated locally, around 3500 BCE. Dogs were the primary source of animal protein in ancient Mesoamerica, and dog bones are common in midden deposits throughout the region. Societies of this region did hunt certain wild species for food. These animals included deer, rabbit , birds, and various types of insects. They also hunted for luxury items, such as feline fur and bird plumage. Mesoamerican cultures that lived in

3294-522: Is one of the six areas in the world where ancient civilization arose independently (see cradle of civilization ), and the second in the Americas, alongside the Caral–Supe in present-day Peru . Mesoamerica is also one of only five regions of the world where writing is known to have independently developed (the others being ancient Egypt , India , Sumer , and China ). Beginning as early as 7000 BCE,

3416-497: Is placed by some between 4 and 8 million years ago, that is, during the Late Miocene. This geochronology article is a stub . You can help Misplaced Pages by expanding it . Miocene As Earth went from the Oligocene through the Miocene and into the Pliocene, the climate slowly cooled towards a series of ice ages . The Miocene boundaries are not marked by distinct global events but by regionally defined transitions from

3538-651: Is the largest lake in Mesoamerica. Lake Chapala is Mexico's largest freshwater lake, but Lake Texcoco is perhaps most well known as the location upon which Tenochtitlan , capital of the Aztec Empire, was founded. Lake Petén Itzá , in northern Guatemala, is notable as where the last independent Maya city, Tayasal (or Noh Petén), held out against the Spanish until 1697. Other large lakes include Lake Atitlán , Lake Izabal , Lake Güija , Lemoa and Lake Xolotlan . Almost all ecosystems are present in Mesoamerica;

3660-630: The Cora and Huichol , the Chontales, the Huaves, and the Pipil, Xincan and Lencan peoples of Central America. Central American Area: Los Naranjos By roughly 6000 BCE, hunter-gatherers living in the highlands and lowlands of Mesoamerica began to develop agricultural practices with early cultivation of squash and chili. The earliest example of maize dates to c. 4000 BCE and comes from Guilá Naquitz ,

3782-481: The International Commission on Stratigraphy : Regionally, other systems are used, based on characteristic land mammals; some of them overlap with the preceding Oligocene and following Pliocene Epochs: Continents continued to drift toward their present positions. Of the modern geologic features, only the land bridge between South America and North America was absent, although South America

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3904-675: The Itza at Tayasal and the Kowoj at Zacpeten , remained independent until 1697. Some Mesoamerican cultures never achieved dominant status or left impressive archaeological remains but are nevertheless noteworthy. These include the Otomi , Mixe–Zoque groups (which may or may not have been related to the Olmecs), the northern Uto-Aztecan groups, often referred to as the Chichimeca , that include

4026-915: The Kaqchikel at Iximche in the Guatemalan highlands. The Pipil resided in El Salvador , the Nicarao were in western Nicaragua and northwestern Costa Rica , and the Ch'orti' were in eastern Guatemala and northwestern Honduras . In central Mexico, the early portion of the Postclassic correlates with the rise of the Toltec and an empire based at their capital, Tula (also known as Tollan ). Cholula , initially an important Early Classic center contemporaneous with Teotihuacan, maintained its political structure (it did not collapse) and continued to function as

4148-559: The Middle Miocene Climate Transition (MMCT). Abrupt increases in opal deposition indicate this cooling was driven by enhanced drawdown of carbon dioxide via silicate weathering. The MMCT caused a sea surface temperature (SST) drop of approximately 6 °C in the North Atlantic. The drop in benthic foraminiferal δ O values was most noticeable in the waters around Antarctica, suggesting cooling

4270-945: The Monte Alto Culture may have preceded the Olmec. Radiocarbon samples associated with various sculptures found at the Late Preclassic site of Izapa suggest a date of between 1800 and 1500 BCE. During the Middle and Late Preclassic period, the Maya civilization developed in the southern Maya highlands and lowlands, and at a few sites in the northern Maya lowlands. The earliest Maya sites coalesced after 1000 BCE, and include Nakbe , El Mirador , and Cerros . Middle to Late Preclassic Maya sites include Kaminaljuyú , Cival , Edzná , Cobá , Lamanai , Komchen , Dzibilchaltun , and San Bartolo , among others. The Preclassic in

4392-545: The Old World . Around the end of this epoch, the ancestors of humans had split away from the ancestors of the chimpanzees and had begun following their own evolutionary path during the final Messinian Stage (7.5–5.3 Ma) of the Miocene. As in the Oligocene before it, grasslands continued to expand, and forests to dwindle. In the seas of the Miocene, kelp forests made their first appearance and soon became one of Earth's most productive ecosystems. The plants and animals of

4514-483: The Postclassic are differentiated by the cyclical crystallization and fragmentation of the various political entities throughout Mesoamerica. The Mesoamerican Paleo-Indian period precedes the advent of agriculture and is characterized by a nomadic hunting and gathering subsistence strategy. Big-game hunting, similar to that seen in contemporaneous North America, was a large component of the subsistence strategy of

4636-701: The Purépecha ) were located in Michoacán and Guerrero. With their capital at Tzintzuntzan , the Tarascan state was one of the few to actively and continuously resist Aztec domination during the Late Postclassic. Other important Postclassic cultures in Mesoamerica include the Totonac along the eastern coast (in the modern-day states of Veracruz , Puebla , and Hidalgo ). The Huastec resided north of

4758-517: The Spanish colonization of the Americas began on Hispaniola in 1493. In world history, Mesoamerica was the site of two historical transformations: (i) primary urban generation, and (ii) the formation of New World cultures from the mixtures of the indigenous Mesoamerican peoples with the European, African, and Asian peoples who were introduced by the Spanish colonization of the Americas. Mesoamerica

4880-663: The Ulúa River , and the Hondo River . The northern Maya lowlands, especially the northern portion of the Yucatán peninsula, are notable for their nearly complete lack of rivers (largely due to the absolute lack of topographic variation). Additionally, no lakes exist in the northern peninsula. The main source of water in this area is aquifers that are accessed through natural surface openings called cenotes . With an area of 8,264 km (3,191 sq mi), Lake Nicaragua

5002-732: The Yucatán Peninsula . Other areas include Central Mexico, West Mexico, the Gulf Coast Lowlands, Oaxaca , the Southern Pacific Lowlands, and Southeast Mesoamerica (including northern Honduras ). There is extensive topographic variation in Mesoamerica, ranging from the high peaks circumscribing the Valley of Mexico and within the central Sierra Madre mountains to the low flatlands of the northern Yucatán Peninsula. The tallest mountain in Mesoamerica

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5124-560: The carbon cycle occurred approximately 6 Ma, causing continental carbon reservoirs to no longer expand during cold spells, as they had done during cold periods in the Oligocene and most of the Miocene. At the end of the Miocene, global temperatures rose again as the amplitude of Earth's obliquity increased, which caused increased aridity in Central Asia. Around 5.5 Ma, the EAWM underwent a period of rapid intensification. Life during

5246-574: The wheel and basic metallurgy , neither of these became technologically relevant. Among the earliest complex civilizations was the Olmec culture, which inhabited the Gulf Coast of Mexico and extended inland and southwards across the Isthmus of Tehuantepec . Frequent contact and cultural interchange between the early Olmec and other cultures in Chiapas , Oaxaca , and Guatemala laid the basis for

5368-470: The 16 volumes of The Handbook of Middle American Indians . "Mesoamerica" is broadly defined as the area that is home to the Mesoamerican civilization, which comprises a group of peoples with close cultural and historical ties. The exact geographic extent of Mesoamerica has varied through time, as the civilization extended North and South from its heartland in southern Mexico. The term was first used by

5490-432: The 16th century. Eurasian diseases such as smallpox and measles , which were endemic among the colonists but new to North America, caused the deaths of upwards of 90% of the indigenous people, resulting in great losses to their societies and cultures. Over the next centuries, Mesoamerican indigenous cultures were gradually subjected to Spanish colonial rule. Aspects of the Mesoamerican cultural heritage still survive among

5612-710: The Central Paratethys, cut off from sources of freshwater input by its separation from the Eastern Paratethys. From 13.36 to 12.65 Ma, the Central Paratethys was characterised by open marine conditions, before the reopening of the Bârlad Strait resulted in a shift to brackish-marine conditions in the Central Paratethys, causing the Badenian-Sarmatian Extinction Event. As a result of the Bârlad Strait's reopening,

5734-404: The Chiapas highlands, and Kaminaljuyú in the central Guatemala highlands, were important southern highland Maya centers. The latter site, Kaminaljuyú, is one of the longest occupied sites in Mesoamerica and was continuously inhabited from c. 800 BCE to around 1200 CE. Other important highland Maya groups include the Kʼicheʼ of Utatlán , the Mam in Zaculeu , the Poqomam in Mixco Viejo , and

5856-721: The Early to the Middle Miocene. Europe's large mammal diversity significantly declined during the Late Miocene. In the Early Miocene, several Oligocene groups were still diverse, including nimravids , entelodonts , and three-toed equids. As in the previous Oligocene Epoch, oreodonts were still diverse, only to disappear in the earliest Pliocene. During the later Miocene mammals were more modern, with easily recognizable canids , bears , red pandas , procyonids , equids , beavers , deer , camelids , and whales , along with now-extinct groups like borophagine canids , certain gomphotheres , three-toed horses , and hornless rhinos like Teleoceras and Aphelos . The late Miocene also marks

5978-402: The East Antarctic Ice Sheet (EAIS) was highly dynamic during the Early Miocene. The Miocene began with the Early Miocene Cool Event (Mi-1) around 23 million years ago, which marked the start of the Early Miocene Cool Interval (EMCI). This cool event occurred immediately after the Oligocene-Miocene Transition (OMT) during a major expansion of Antarctica's ice sheets, but was not associated with

6100-399: The East Asian Winter Monsoon (EAWM) became stronger synchronously with a southward shift of the subarctic front. Greenland may have begun to have large glaciers as early as 8 to 7 Ma, although the climate for the most part remained warm enough to support forests there well into the Pliocene. Zhejiang, China was noticeably more humid than today. In the Great Rift Valley of Kenya , there

6222-445: The German ethnologist Paul Kirchhoff , who noted that similarities existed among the various pre-Columbian cultures within the region that included southern Mexico, Guatemala , Belize , El Salvador , western Honduras , and the Pacific lowlands of Nicaragua and northwestern Costa Rica . In the tradition of cultural history , the prevalent archaeological theory of the early to middle 20th century, Kirchhoff defined this zone as

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6344-404: The Isthmus is swampy and covered in dense jungle—but the Isthmus of Tehuantepec, as the lowest and most level point within the Sierra Madre mountain chain, was nonetheless a main transportation, communication, and economic route within Mesoamerica. Outside of the northern Maya lowlands, rivers are common throughout Mesoamerica. Some of the more important ones served as loci of human occupation in

6466-411: The LMC; extratropical sea surface temperatures dropped substantially by approximately 7–9 °C. 41 kyr obliquity cycles became the dominant orbital climatic control 7.7 Ma and this dominance strengthened 6.4 Ma. Benthic δ O values show significant glaciation occurred from 6.26 to 5.50 Ma, during which glacial-interglacial cycles were governed by the 41 kyr obliquity cycle. A major reorganisation of

6588-405: The Late Cretaceous, are known from the Miocene of Patagonia, represented by the mole-like Necrolestes . The youngest known representatives of metatherians (the broader grouping to which marsupials belong) in Europe, Asia and Africa are known from the Miocene, including the European herpetotheriid Amphiperatherium , the peradectids Siamoperadectes and Sinoperadectes from Asia, and

6710-591: The Late Miocene, the Earth's climate began to display a high degree of similarity to that of the present day . The 173 kyr obliquity modulation cycle governed by Earth's interactions with Saturn became detectable in the Late Miocene. By 12 Ma, Oregon was a savanna akin to that of the western margins of the Sierra Nevada of northern California . Central Australia became progressively drier, although southwestern Australia experienced significant wettening from around 12 to 8 Ma. The South Asian Winter Monsoon (SAWM) underwent strengthening ~9.2–8.5 Ma. From 7.9 to 5.8 Ma,

6832-444: The Mediterranean Sea to almost completely evaporate. This event is referred to as the " Messinian salinity crisis ". Then, at the Miocene–Pliocene boundary, the Strait of Gibraltar opened, and the Mediterranean refilled. That event is referred to as the " Zanclean flood ". Also during the early Miocene (specifically the Aquitanian and Burdigalian Stages), the apes first evolved, began diversifying, and became widespread throughout

6954-401: The Mesoamerican Paleo-Indian. These sites had obsidian blades and Clovis -style fluted projectile points . The Archaic period (8000–2000 BCE) is characterized by the rise of incipient agriculture in Mesoamerica. The initial phases of the Archaic involved the cultivation of wild plants, transitioning into informal domestication and culminating with sedentism and agricultural production by

7076-429: The Mesoamerican cultural area. All this was facilitated by considerable regional communications in ancient Mesoamerica , especially along the Pacific coast. In the subsequent Preclassic period , complex urban polities began to develop among the Maya , with the rise of centers such as Aguada Fénix and Calakmul in Mexico; El Mirador , and Tikal in Guatemala, and the Zapotec at Monte Albán . During this period,

7198-511: The Miocene Epoch was mostly supported by the two newly formed biomes , kelp forests and grasslands . Grasslands allow for more grazers, such as horses , rhinoceroses , and hippos . Ninety-five percent of modern plants existed by the end of this epoch . Modern bony fish genera were established. A modern-style latitudinal biodiversity gradient appeared ~15 Ma. The coevolution of gritty , fibrous, fire-tolerant grasses and long-legged gregarious ungulates with high-crowned teeth , led to

7320-483: The Miocene were recognizably modern. Mammals and birds were well established. Whales , pinnipeds , and kelp spread. The Miocene is of particular interest to geologists and palaeoclimatologists because major phases of the geology of the Himalaya occurred during that epoch, affecting monsoonal patterns in Asia, which were interlinked with glacial periods in the northern hemisphere. The Miocene faunal stages from youngest to oldest are typically named according to

7442-449: The Miocene. The largest form among them was a gigantic caiman Purussaurus which inhabited South America. Another gigantic form was a false gharial Rhamphosuchus , which inhabited modern age India . A strange form, Mourasuchus also thrived alongside Purussaurus . This species developed a specialized filter-feeding mechanism, and it likely preyed upon small fauna despite its gigantic size. The youngest members of Sebecidae ,

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7564-413: The North American Great Plains and in Argentina . The global trend was towards increasing aridity caused primarily by global cooling reducing the ability of the atmosphere to absorb moisture, particularly after 7 to 8 million years ago. Uplift of East Africa in the late Miocene was partly responsible for the shrinking of tropical rain forests in that region, and Australia got drier as it entered

7686-529: The Oligocene–Miocene transgression. As the southern Andes rose in the Middle Miocene (14–12 million years ago) the resulting rain shadow originated the Patagonian Desert to the east. Far northern Australia was monsoonal during the Miocene. Although northern Australia is often believed to have been much wetter during the Miocene, this interpretation may be an artefact of preservation bias of riparian and lacustrine plants; this finding has itself been challenged by other papers. Western Australia, like today,

7808-405: The Olmec include San Lorenzo Tenochtitlán , La Venta , and Tres Zapotes . Specific dates vary, but these sites were occupied from roughly 1200 to 400 BCE. Remains of other early cultures interacting with the Olmec have been found at Takalik Abaj , Izapa , and Teopantecuanitlan , and as far south as in Honduras . Research in the Pacific Lowlands of Chiapas and Guatemala suggest that Izapa and

7930-433: The Qiongdongnan Basin in the northern South China Sea indicates the Pearl River was a major source of sediment flux into the sea during the Early Miocene and was a major fluvial system as in the present. During the Oligocene and Early Miocene, the coast of northern Brazil, Colombia, south-central Peru , central Chile and large swathes of inland Patagonia were subject to a marine transgression . The transgressions in

8052-421: The Totonac, mainly in the modern-day states of Tamaulipas and northern Veracruz. The Mixtec and Zapotec cultures, centered at Mitla and Zaachila respectively, inhabited Oaxaca. The Postclassic ends with the arrival of the Spanish and their subsequent conquest of the Aztecs between 1519 and 1521. Many other cultural groups did not acquiesce until later. For example, Maya groups in the Petén area, including

8174-427: The Trans-Mexican volcanic belt. There are 83 inactive and active volcanoes within the Sierra Madre range, including 11 in Mexico, 37 in Guatemala, 23 in El Salvador, 25 in Nicaragua, and 3 in northwestern Costa Rica. According to the Michigan Technological University, 16 of these are still active. The tallest active volcano is Popocatépetl at 5,452 m (17,887 ft). This volcano, which retains its Nahuatl name,

8296-423: The activity of the Columbia River Basalts and enhanced by decreased albedo from the reduction of deserts and expansion of forests. Climate modelling suggests additional, currently unknown, factors also worked to create the warm conditions of the MMCO. The MMCO saw the expansion of the tropical climatic zone to much larger than its current size. The July ITCZ, the zone of maximal monsoonal rainfall, moved to

8418-401: The area. The longest river in Mesoamerica is the Usumacinta , which forms in Guatemala at the convergence of the Salinas or Chixoy and La Pasión River and runs north for 970 km (600 mi)—480 km (300 mi) of which are navigable—eventually draining into the Gulf of Mexico . Other rivers of note include the Río Grande de Santiago , the Grijalva River , the Motagua River ,

8540-472: The aridity of the former. Unequivocally-recognizable dabbling ducks , plovers , typical owls , cockatoos and crows appear during the Miocene. By the epoch's end, all or almost all modern bird groups are believed to have been present; the few post-Miocene bird fossils which cannot be placed in the evolutionary tree with full confidence are simply too badly preserved, rather than too equivocal in character. Marine birds reached their highest diversity ever in

8662-422: The beginning of the Miocene, the northern margin of the Arabian plate, then part of the African landmass, collided with Eurasia; as a result, the Tethys seaway continued to shrink and then disappeared as Africa collided with Eurasia in the Turkish – Arabian region. The first step of this closure occurred 20 Ma, reducing water mass exchange by 90%, while the second step occurred around 13.8 Ma, coincident with

8784-440: The central Mexican highlands is represented by such sites as Tlapacoya , Tlatilco , and Cuicuilco . These sites were eventually superseded by Teotihuacán , an important Classic-era site that eventually dominated economic and interaction spheres throughout Mesoamerica. The settlement of Teotihuacan is dated to the later portion of the Late Preclassic, or roughly 50 CE. In the Valley of Oaxaca , San José Mogote represents one of

8906-539: The close of the period. Transformations of natural environments have been a common feature at least since the mid Holocene. Archaic sites include Sipacate in Escuintla , Guatemala, where maize pollen samples date to c. 3500 BCE. The first complex civilization to develop in Mesoamerica was that of the Olmec , who inhabited the Gulf Coast region of Veracruz throughout the Preclassic period. The main sites of

9028-571: The collapse of Teotihuacán around 600 CE, competition between several important political centers in central Mexico, such as Xochicalco and Cholula , ensued. At this time during the Epi-Classic period, the Nahua peoples began moving south into Mesoamerica from the North, and became politically and culturally dominant in central Mexico, as they displaced speakers of Oto-Manguean languages . During

9150-592: The control of a Toltec empire. Chronological data refutes this early interpretation, and it is now known that Chichén Itzá predated the Toltec; Mexican architectural styles are now used as an indicator of strong economic and ideological ties between the two regions. The Postclassic (beginning 900–1000 CE, depending on area) is, like the Late Classic, characterized by the cyclical crystallization and fragmentation of various polities. The main Maya centers were located in

9272-577: The course of this epoch . The youngest representatives of Choristodera , an extinct order of aquatic reptiles that first appeared in the Middle Jurassic , are known from the Miocene of Europe, belonging to the genus Lazarussuchus , which had been the only known surviving genus of the group since the beginning of the Eocene. The last known representatives of the archaic primitive mammal order Meridiolestida , which dominated South America during

9394-426: The domestication of cacao , maize , beans , tomato , avocado , vanilla , squash and chili , as well as the turkey and dog , resulted in a transition from paleo-Indian hunter-gatherer tribal groupings to the organization of sedentary agricultural villages. In the subsequent Formative period, agriculture and cultural traits such as a complex mythological and religious tradition , a vigesimal numeric system,

9516-417: The dominant climate is temperate with warm temperatures and moderate rainfall. The rainfall varies from the dry Oaxaca and north Yucatán to the humid southern Pacific and Caribbean lowlands. Several distinct sub-regions within Mesoamerica are defined by a convergence of geographic and cultural attributes. These sub-regions are more conceptual than culturally meaningful, and the demarcation of their limits

9638-518: The early post-Classic period, Central Mexico was dominated by the Toltec culture, and Oaxaca by the Mixtec . The lowland Maya area had important centers at Chichén Itzá and Mayapán . Towards the end of the post-Classic period, the Aztecs of Central Mexico built a tributary empire covering most of central Mesoamerica. The distinct Mesoamerican cultural tradition ended with the Spanish conquest in

9760-566: The early to mid Miocene (23–15 Ma). Oceans cooled partly due to the formation of the Antarctic Circumpolar Current , and about 15 million years ago the ice cap in the southern hemisphere started to grow to its present form. The Greenland ice cap developed later, in the Middle Pliocene time, about 3 million years ago. Mesoamerica Mesoamerica is a historical region and cultural area that begins in

9882-578: The end of the Miocene due to increased habitat uniformity. The expansion of grasslands in North America also led to an explosive radiation among snakes. Previously, snakes were a minor component of the North American fauna, but during the Miocene, the number of species and their prevalence increased dramatically with the first appearances of vipers and elapids in North America and the significant diversification of Colubridae (including

10004-485: The end of the Miocene. The Paratethys underwent a significant transgression during the early Middle Miocene. Around 13.8 Ma, during a global sea level drop, the Eastern Paratethys was cut off from the global ocean by the closure of the Bârlad Strait, effectively turning it into a saltwater lake. From 13.8 to 13.36 Ma, an evaporite period similar to the later Messinian salinity crisis in the Mediterranean ensued in

10126-637: The enigmatic Saint Bathans Mammal . Microbial life in the igneous crust of the Fennoscandian Shield shifted from being dominated by methanogens to being primarily composed of sulphate-reducing prokaryotes . The change resulted from fracture reactivation during the Pyrenean-Alpine orogeny, enabling sulphate-reducing microbes to permeate into the Fennoscandian Shield via descending surficial waters. Diatom diversity

10248-461: The evolution of both groups into modern representatives. The early Miocene Saint Bathans Fauna is the only Cenozoic terrestrial fossil record of the landmass, showcasing a wide variety of not only bird species, including early representatives of clades such as moa , kiwi and adzebills , but also a diverse herpetofauna of sphenodontians , crocodiles and turtles as well as a rich terrestrial mammal fauna composed of various species of bats and

10370-499: The expansion of grasslands not to a CO 2 drop but to the increasing seasonality and aridity, coupled with a monsoon climate, which made wildfires highly prevalent compared to before. The Late Miocene expansion of grasslands had cascading effects on the global carbon cycle, evidenced by the imprint it left in carbon isotope records. Cycads between 11.5 and 5 million years ago began to rediversify after previous declines in variety due to climatic changes, and thus modern cycads are not

10492-771: The extinction of the last-surviving members of the hyaenodonts . Islands began to form between South and North America in the Late Miocene, allowing ground sloths like Thinobadistes to island-hop to North America. The expansion of silica-rich C 4 grasses led to worldwide extinctions of herbivorous species without high-crowned teeth . Mustelids diversified into their largest forms as terrestrial predators like Ekorus , Eomellivora , and Megalictis and bunodont otters like Enhydriodon and Sivaonyx appeared. Eulipotyphlans were widespread in Europe, being less diverse in Southern Europe than farther north due to

10614-629: The findings of marine invertebrate fossils of both Atlantic and Pacific affinity in La Cascada Formation . Connection would have occurred through narrow epicontinental seaways that formed channels in a dissected topography . The Antarctic Plate started to subduct beneath South America 14 million years ago in the Miocene, forming the Chile Triple Junction . At first the Antarctic Plate subducted only in

10736-591: The first true Mesoamerican writing systems were developed in the Epi-Olmec and the Zapotec cultures. The Mesoamerican writing tradition reached its height in the Classic Maya logosyllabic script . In Central Mexico, the city of Teotihuacan ascended at the height of the Classic period; it formed a military and commercial empire whose political influence stretched south into the Maya area and northward. Upon

10858-464: The human lineage) appeared in Africa at the very end of the Miocene, including Sahelanthropus , Orrorin , and an early form of Ardipithecus ( A. kadabba ). The chimpanzee–human divergence is thought to have occurred at this time. The evolution of bipedalism in apes at the end of the Miocene instigated an increased rate of faunal turnover in Africa. In contrast, European apes met their end at

10980-457: The indigenous peoples who inhabit Mesoamerica. Many continue to speak their ancestral languages and maintain many practices hearkening back to their Mesoamerican roots. The term Mesoamerica literally means "middle America" in Greek. Middle America often refers to a larger area in the Americas, but it has also previously been used more narrowly to refer to Mesoamerica. An example is the title of

11102-606: The lake levels of the Eastern Paratethys dropped as it once again became a sea. The Fram Strait opened during the Miocene and acted as the only throughflow for Atlantic Water into the Arctic Ocean until the Quaternary period. Due to regional uplift of the continental shelf, this water could not move through the Barents Seaway in the Miocene. The modern day Mekong Delta took shape after 8 Ma. Geochemistry of

11224-565: The lowlands (those areas between sea level and 1000 meters) and the altiplanos , or highlands (situated between 1,000 and 2,000 meters above sea level). In the low-lying regions, sub-tropical and tropical climates are most common, as is true for most of the coastline along the Pacific and Gulf of Mexico and the Caribbean Sea . The highlands show much more climatic diversity, ranging from dry tropical to cold mountainous climates ;

11346-421: The lowlands and coastal plains settled down in agrarian communities somewhat later than did highland cultures because there was a greater abundance of fruits and animals in these areas, which made a hunter-gatherer lifestyle more attractive. Fishing also was a major provider of food to lowland and coastal Mesoamericans creating a further disincentive to settle down in permanent communities. Ceremonial centers were

11468-633: The more well known are the Mesoamerican Barrier Reef System , the second largest in the world, and La Mosquitia (consisting of the Río Plátano Biosphere Reserve , Tawahka Asangni, Patuca National Park , and Bosawás Biosphere Reserve ) a rainforest second in size in the Americas only to the Amazonas . The highlands present mixed and coniferous forest. The biodiversity is among the richest in

11590-547: The north, increasing precipitation over southern China whilst simultaneously decreasing it over Indochina during the EASM. Western Australia was at this time characterised by exceptional aridity. In Antarctica, average summer temperatures on land reached 10 °C. In the oceans, the lysocline shoaled by approximately half of a kilometre during warm phases that corresponded to orbital eccentricity maxima. The MMCO ended around 14 million years ago, when global temperatures fell in

11712-504: The northern lowlands. Generally applied to the Maya area, the Terminal Classic roughly spans the time between c. 800/850 and c. 1000 CE. Overall, it generally correlates with the rise to prominence of Puuc settlements in the northern Maya lowlands , so named after the hills where they are mainly found. Puuc settlements are specifically associated with a unique architectural style (the "Puuc architectural style") that represents

11834-574: The northern lowlands. Following Chichén Itzá, whose political structure collapsed during the Early Postclassic, Mayapán rose to prominence during the Middle Postclassic and dominated the north for c. 200 years. After Mayapán's fragmentation, the political structure in the northern lowlands revolved around large towns or city-states, such as Oxkutzcab and Ti’ho ( Mérida, Yucatán ), that competed with one another. Toniná , in

11956-415: The nuclei of Mesoamerican settlements. The temples provided spatial orientation, which was imparted to the surrounding town. The cities with their commercial and religious centers were always political entities, somewhat similar to the European city-state , and each person could identify with the city where they lived. Ceremonial centers were always built to be visible. Pyramids were meant to stand out from

12078-449: The oldest permanent agricultural villages in the area, and one of the first to use pottery. During the Early and Middle Preclassic, the site developed some of the earliest examples of defensive palisades , ceremonial structures, the use of adobe , and hieroglyphic writing . Also of importance, the site was one of the first to demonstrate inherited status , signifying a radical shift in socio-cultural and political structure. San José Mogote

12200-523: The origin of many modern genera such as Nerodia , Lampropeltis , Pituophis and Pantherophis ). Arthropods were abundant, including in areas such as Tibet where they have traditionally been thought to be undiverse. Neoisopterans diversified and expanded into areas they previously were absent from, such as Madagascar and Australia. In the oceans, brown algae , called kelp , proliferated, supporting new species of sea life, including otters , fish and various invertebrates . Corals suffered

12322-687: The past few decades has established that it was first settled during the Early/Late Classic transition but rose to prominence during the Terminal Classic and Early Postclassic. During its apogee, this widely known site economically and politically dominated the northern lowlands. Its participation in the circum-peninsular exchange route, possible through its port site of Isla Cerritos , allowed Chichén Itzá to remain highly connected to areas such as central Mexico and Central America. The apparent "Mexicanization" of architecture at Chichén Itzá led past researchers to believe that Chichén Itzá existed under

12444-463: The possible herpetotheriid Morotodon from the late Early Miocene of Uganda. Approximately 100 species of apes lived during this time , ranging throughout Africa, Asia and Europe and varying widely in size, diet, and anatomy. Due to scanty fossil evidence it is unclear which ape or apes contributed to the modern hominid clade, but molecular evidence indicates this ape lived between 18 and 13 million years ago. The first hominins ( bipedal apes of

12566-416: The rest of the city, to represent the gods and their powers. Another characteristic feature of the ceremonial centers is historic layers. All the ceremonial edifices were built in various phases, one on top of the other, to the point that what we now see is usually the last stage of construction. Ultimately, the ceremonial centers were the architectural translation of the identity of each city, as represented by

12688-493: The southern part of North America and extends to the Pacific coast of Central America, thus comprising the lands of central and southern Mexico, all of Belize , Guatemala , El Salvador , and parts of Honduras , Nicaragua and Costa Rica . As a cultural area, Mesoamerica is defined by a mosaic of cultural traits developed and shared by its indigenous cultures. In the pre-Columbian era , many indigenous societies flourished in Mesoamerica for more than 3,000 years before

12810-714: The southernmost tip of Patagonia, meaning that the Chile Triple Junction lay near the Strait of Magellan . As the southern part of Nazca Plate and the Chile Rise became consumed by subduction the more northerly regions of the Antarctic Plate begun to subduct beneath Patagonia so that the Chile Triple Junction advanced to the north over time. The asthenospheric window associated to the triple junction disturbed previous patterns of mantle convection beneath Patagonia inducing an uplift of ca. 1 km that reversed

12932-633: The time following the arrival of the Spanish in the 16th century is classified as the Colonial period. The differentiation of early periods (i.e., up through the end of the Late Preclassic ) generally reflects different configurations of socio-cultural organization that are characterized by increasing socio-political complexity , the adoption of new and different subsistence strategies , and changes in economic organization (including increased interregional interaction). The Classic period through

13054-411: The veneration of their gods and masters. Stelae were common public monuments throughout Mesoamerica and served to commemorate notable successes, events, and dates associated with the rulers and nobility of the various sites. Given that Mesoamerica was broken into numerous and diverse ecological niches, none of the societies that inhabited the area were self-sufficient, although very long-distance trade

13176-474: The warmer Oligocene to the cooler Pliocene Epoch. During the Early Miocene, Afro-Arabia collided with Eurasia, severing the connection between the Mediterranean and Indian Oceans, and allowing the interchange of fauna between Eurasia and Africa, including the dispersal of proboscideans and hominoids into Eurasia. During the late Miocene, the connections between the Atlantic and Mediterranean closed, causing

13298-609: The west coast of South America are thought to be caused by a regional phenomenon while the steadily rising central segment of the Andes represents an exception. While there are numerous registers of Oligocene–Miocene transgressions around the world it is doubtful that these correlate. It is thought that the Oligocene–Miocene transgression in Patagonia could have temporarily linked the Pacific and Atlantic Oceans, as inferred from

13420-542: The western United States, respectively, have not entered into widespread usage. Some of the significant cultural traits defining the Mesoamerican cultural tradition are: Located on the Middle American isthmus joining North and South America between ca. 10° and 22° northern latitude , Mesoamerica possesses a complex combination of ecological systems, topographic zones, and environmental contexts. These different niches are classified into two broad categories:

13542-759: The world, though the number of species in the red list of the IUCN grows every year. The history of human occupation in Mesoamerica is divided into stages or periods. These are known, with slight variation depending on region, as the Paleo-Indian , the Archaic , the Preclassic (or Formative), the Classic , and the Postclassic . The last three periods, representing the core of Mesoamerican cultural fluorescence, are further divided into two or three sub-phases. Most of

13664-423: Was Allodesmus . A ferocious walrus , Pelagiarctos may have preyed upon other species of pinnipeds including Allodesmus . Furthermore, South American waters witnessed the arrival of Megapiranha paranensis , which were considerably larger than modern age piranhas . New Zealand 's Miocene fossil record is particularly rich. Marine deposits showcase a variety of cetaceans and penguins , illustrating

13786-624: Was a gradual and progressive trend of increasing aridification, though it was not unidirectional, and wet humid episodes continued to occur. Between 7 and 5.3 Ma, temperatures dropped sharply again in the Late Miocene Cooling (LMC), most likely as a result of a decline in atmospheric carbon dioxide and a drop in the amplitude of Earth's obliquity, and the Antarctic ice sheet was approaching its present-day size and thickness. Ocean temperatures plummeted to near-modern values during

13908-514: Was allied with Caracol and may have assisted in the defeat of Tikal), and Dos Pilas Aguateca and Cancuén in the Petexbatún region of Guatemala. Around 710, Tikal arose again and started to build strong alliances and defeat its worst enemies. In the Maya area, the Late Classic ended with the so-called " Maya collapse ", a transitional period coupling the general depopulation of the southern lowlands and development and florescence of centers in

14030-591: Was approaching the western subduction zone in the Pacific Ocean , causing both the rise of the Andes and a southward extension of the Meso-American peninsula. Mountain building took place in western North America , Europe , and East Asia . Both continental and marine Miocene deposits are common worldwide with marine outcrops common near modern shorelines. Well studied continental exposures occur in

14152-584: Was arid, particularly so during the Middle Miocene. Climates remained moderately warm, although the slow global cooling that eventually led to the Pleistocene glaciations continued. Although a long-term cooling trend was well underway, there is evidence of a warm period during the Miocene when the global climate rivalled that of the Oligocene . The climate of the Miocene has been suggested as

14274-400: Was common only for very rare goods, or luxury materials. For this reason, from the last centuries of the Archaic period (8000 BCE– 1000 BCE) onward, regions compensated for the environmental inadequacies by specializing in the extraction of certain abundant natural resources and then trading them for necessary unavailable resources through established commercial trade networks. The following

14396-531: Was eventually overtaken by Monte Albán , the subsequent capital of the Zapotec empire , during the Late Preclassic. The Preclassic in western Mexico, in the states of Nayarit , Jalisco , Colima , and Michoacán also known as the Occidente, is poorly understood. This period is best represented by the thousands of figurines recovered by looters and ascribed to the " shaft tomb tradition ". The Classic period

14518-688: Was inversely correlated with carbon dioxide levels and global temperatures during the Miocene. Most modern lineages of diatoms appeared by the Late Miocene. There is evidence from oxygen isotopes at Deep Sea Drilling Program sites that ice began to build up in Antarctica about 36 Ma during the Eocene . Further marked decreases in temperature during the Middle Miocene at 15 Ma probably reflect increased ice growth in Antarctica. It can therefore be assumed that East Antarctica had some glaciers during

14640-646: Was most intense there. Around this time the Mi3b glacial event (a massive expansion of Antarctic glaciers) occurred. The East Antarctic Ice Sheet (EAIS) markedly stabilised following the MMCT. The intensification of glaciation caused a decoherence of sediment deposition from the 405 kyr eccentricity cycle. The MMWI ended about 11 Ma, when the Late Miocene Cool Interval (LMCI) started. A major but transient warming occurred around 10.8-10.7 Ma. During

14762-589: Was predominantly used by the Maya during the Early Classic), and jade from the Motagua valley in Guatemala. Tikal was often in conflict with other polities in the Petén Basin , as well as with others outside of it, including Uaxactun , Caracol , Dos Pilas , Naranjo , and Calakmul . Towards the end of the Early Classic, this conflict lead to Tikal's military defeat at the hands of Caracol in 562, and

14884-506: Was the staple crop in the region, and remained so through modern times. The Ramón or Breadnut tree ( Brosimum alicastrum ) was an occasional substitute for maize in producing flour. Fruit was also important in the daily diet of Mesoamerican cultures. Some of the main ones consumed include avocado , papaya , guava , mamey , zapote , and annona . Mesoamerica lacked animals suitable for domestication, most notably domesticated large ungulates . The lack of draft animals for transportation

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