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Sunday, August 5, 2018

Mesoamerica

From Wikipedia, the free encyclopedia

Mesoamerica and its cultural areas
 
Page 9 of the Dresden Codex (from the 1880 Förstermann edition)

Mesoamerica is a historical region and cultural area in the Americas, extending from approximately central Mexico through Belize, Guatemala, El Salvador, Honduras, Nicaragua, and northern Costa Rica, and within which pre-Columbian societies flourished before the Spanish colonization of the Americas in the 15th and 16th centuries. It is one of six areas in the world where ancient civilization arose independently, and the second in the Americas along with Norte Chico (Caral-Supe) in present-day northern coastal Peru.

As a cultural area, Mesoamerica is defined by a mosaic of cultural traits developed and shared by its indigenous cultures. Beginning as early as 7000 BC, the domestication of cacao, maize, beans, tomato, avocado, vanilla, squash and chili, as well as the turkey and dog, caused a transition from paleo-Indian hunter-gatherer tribal grouping 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, and a complex calendric system, a tradition of ball playing, and a distinct architectural style, were diffused through the area. Also in this period, villages began to become socially stratified and develop into chiefdoms with the development of large ceremonial centers, 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 did know of the wheel and basic metallurgy, neither of these technologies became culturally important.[3]

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, Guatemala and Oaxaca laid the basis for the Mesoamerican cultural area. All this was facilitated by considerable regional communications in ancient Mesoamerica, especially along the Pacific coast.

Ballgame court at Monte Albán
 
A pair of swinging Remojadas figurines, Classic Veracruz culture, 300 CE to 900 CE.
 
This formative period saw the spread of distinct religious and symbolic traditions, as well as artistic and architectural complexes. In the subsequent Preclassic period, complex urban polities began to develop among the Maya, with the rise of centers such as El Mirador, Calakmul and Tikal, and the Zapotec at Monte Albán. During this period, the first true Mesoamerican writing systems were developed in the Epi-Olmec and the Zapotec cultures, and the Mesoamerican writing tradition reached its height in the Classic Maya hieroglyphic script.

Mesoamerica is one of only three regions of the world where writing is known to have independently developed (the others being ancient Sumer and China).[4] In Central Mexico, the height of the Classic period saw the ascendancy of the city of Teotihuacan, which formed a military and commercial empire whose political influence stretched south into the Maya area and northward. Upon the collapse of Teotihuacán around AD 600, 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 the early post-Classic period, Central Mexico was dominated by the Toltec culture, Oaxaca by the Mixtec, and 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.[5]

The distinct Mesoamerican cultural tradition ended with the Spanish conquest in the 16th century. Over the next centuries, Mesoamerican indigenous cultures were gradually subjected to Spanish colonial rule. Aspects of the Mesoamerican cultural heritage still survive among the indigenous peoples who inhabit Mesoamerica, many of whom continue to speak their ancestral languages, and maintain many practices harking back to their Mesoamerican roots.[6]

Etymology and definition

Maya Ruins of Tazumal in Santa Ana, El Salvador

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 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 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 a cultural area based on a suite of interrelated cultural similarities brought about by millennia of inter- and intra-regional interaction (i.e., diffusion).[7][8] Mesoamerica is recognized as a near-prototypical cultural area, and the term is now fully integrated in the standard terminology of pre-Columbian anthropological studies. Conversely, the sister terms Aridoamerica and Oasisamerica, which refer to northern Mexico and the western United States, respectively, have not entered into widespread usage.

Some of the significant cultural traits defining the Mesoamerican cultural tradition are:

Geography

El Mirador flourished from 600 BC to AD 100, and may have had a population of over 100,000.
 
Landscape of the Mesoamerican highlands

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. A main distinction groups these different niches into two broad categories: 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).[10][11] 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; 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.

Cultural sub-areas

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 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 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).

Topography

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 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 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,[12] 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, 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, Momotombo in Nicaragua, and Arenal in Costa Rica.

One important topographic feature is the Isthmus of Tehuantepec, 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). Although the northern side of the Isthmus is swampy and covered with dense jungle, 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.

Bodies of water

Outside of the northern Maya lowlands, rivers are common throughout Mesoamerica. Some of the more important ones served as loci of human occupation in the area. The longest river in Mesoamerica is the Usumacinta, which forms in Guatemala at the convergence of the Salinas or Chixoy and La Pasion 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 Rio Grande de Santiago, the Grijalva River, the Motagua River, 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 km2 (3,191 sq mi), Lake Nicaragua 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 the location at which 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 Managua.

Biodiversity

Almost all ecosystems are present in Mesoamerica; the more well known are the Mesoamerican Barrier Reef System, the second largest in the world, and La Mosquitia (consisting of the Rio Platano Biosphere Reserve, Tawahka Asangni, Patuca National Park, and Bosawas Biosphere Reserve) a rainforest second in size in the Americas only to the Amazonas.[13] The highlands present mixed and coniferous forest. The biodiversity is among the richest in the world, although the number of species in the red list of the IUCN is growing every year.

Chronology and culture

Tikal is one of the largest archaeological sites, urban centers, and tourist attractions of the pre-Columbian Maya civilization. It is located in the archaeological region of the Petén Basin in what is now northern Guatemala.

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 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 the Postclassic are differentiated by the cyclical crystallization and fragmentation of the various political entities throughout Mesoamerica.

Paleo-Indian

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 the Mesoamerican Paleo-Indian. These sites had obsidian blades and Clovis-style fluted projectile points.

Archaic

The Archaic period (8000–2000 BC) 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 the close of the period. Transformations of natural environments have been a common feature at least since the mid Holocene [14]. Archaic sites include Sipacate in Escuintla, Guatemala, where maize pollen samples date to c. 3500 BC.[15]

Preclassic/Formative

Olmec Colossal Head No. 3 1200–900 BC

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 the Olmec include San Lorenzo Tenochtitlán, La Venta, and Tres Zapotes. Although specific dates vary, these sites were occupied from roughly 1200 to 400 BC. 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.[16] Research in the Pacific Lowlands of Chiapas and Guatemala suggest that Izapa and 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 BC.[17]

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 BC, 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 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 AD 50.

In the Valley of Oaxaca, San José Mogote represents one of 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 was eventual 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".

Preclassic gallery

  • Sculpture of "The Acrobat" from Tlatilco.
  • Cuicuilco 800–600 BC
  • Nakbé, Mid Preclassic (600 BC) Palace remains, The Mirador Basin
  • The partly excavated main structure of San Jose Mogote 1500–500 BC
  • Monte Alban, Building J in the foreground. 200 BC – AD 200

Classic

Early Classic

Pyramid of the Moon viewed from atop of the Pyramid of the Sun.

The Classic period is marked by the rise and dominance of several polities. The traditional distinction between the Early and Late Classic are 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 Alban in Oaxaca 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 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 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 a period commonly known as the Tikal Hiatus.
Early Classic gallery

Late Classic

Xochicalco, Temple of the Feathered Serpent, AD 650–900

The Late Classic period (beginning ca. AD 600 until AD 909 [varies]) 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 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 the northern lowlands.
Late Classic gallery

Terminal Classic

Detail of the Nunnery Quadrangle at Uxmal, 10th century

Generally applied to the Maya area, the Terminal Classic roughly spans the time between AD 800/850 and ca. AD 1000. Overall, it generally correlates with the rise to prominence of Puuc settlements in the northern Maya lowlands, so named after the hills in which they are mainly found. Puuc settlements are specifically associated with a unique architectural style (the "Puuc architectural style") that represents 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 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 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.
Terminal Classic gallery
  • Chichen Itza, Temple of the Jaguars AD 900–1000
  • Governor's Palace rear view and details, AD 10th century, Uxmal
  • Codz Poop, AD 7th–10th centuries Kabah
  • Sayil, three-story palace, AD 600–900
  • Chichen Itza, "Temple of Three Dintels" AD 600–1000

Postclassic

The Postclassic (beginning AD 900–1000, 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 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, 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.

Mesoamerica and Central America in the 16th century before Spanish arrival

Toniná, in 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 BC to around AD 1200. Other important highland Maya groups include the K'iche' of Utatlán, the Mam in Zaculeu, the Poqomam in Mixco Viejo, and the Kaqchikel at Iximche in the Guatemalan highlands. The Pipil resided in El Salvador, while 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 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 the P'urhépecha) 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 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 Aztec between 1519 and 1521. Many other cultural groups did not acquiesce until later. For example, Maya groups in the Petén area, including 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 the Cora and Huichol, the Chontales, the Huaves, and the Pipil, Xincan and Lencan peoples of Central America.

Postclassic gallery

Chronology in chart form

Period Timespan Important cultures, cities
Summary of the chronology and cultures of Mesoamerica
Paleo-Indian 10,000–3500 BCE Honduras, Guatemala, Belize, obsidian and pyrite points, Iztapan
Archaic 3500–1800 BCE Agricultural settlements, Tehuacán
Preclassic (Formative) 2000 BCE - 250 CE Unknown culture in La Blanca and Ujuxte, Monte Alto culture
Early Preclassic 2000–1000 BCE Olmec area: San Lorenzo Tenochtitlan; Central Mexico: Chalcatzingo; Valley of Oaxaca: San José Mogote. The Maya area: Nakbe, Cerros
Middle Preclassic 1000–400 BCE Olmec area: La Venta, Tres Zapotes; Maya area: El Mirador, Izapa, Lamanai, Xunantunich, Naj Tunich, Takalik Abaj, Kaminaljuyú, Uaxactun; Valley of Oaxaca: Monte Albán
Late Preclassic 400 BC – 200 CE Maya area: Uaxactun, Tikal, Edzná, Cival, San Bartolo, Altar de Sacrificios, Piedras Negras, Ceibal, Rio Azul; Central Mexico: Teotihuacan; Gulf Coast: Epi-Olmec culture; Western Mexico: Shaft Tomb Tradition
Classic 200–900 CE Classic Maya Centers, Teotihuacan, Zapotec
Early Classic 200–600 CE Maya area: Calakmul, Caracol, Chunchucmil, Copán, Naranjo, Palenque, Quiriguá, Tikal, Uaxactun, Yaxha; Central Mexico: Teotihuacan apogee; Zapotec apogee; Western Mexico: Teuchitlan tradition
Late Classic 600–900 CE Maya area: Uxmal, Toniná, Cobá, Waka', Pusilhá, Xultún, Dos Pilas, Cancuen, Aguateca, Yaxchilan; Central Mexico: Xochicalco, Cacaxtla; Gulf Coast: El Tajín and Classic Veracruz culture; Western Mexico: Teuchitlan tradition
Terminal Classic 800–900/1000 CE Maya area: Puuc sites: Uxmal, Labna, Sayil, Kabah
Postclassic 900–1519 AD Aztec, Tarascans, Mixtec, Totonac, Pipil, Itzá, Kowoj, K'iche', Kaqchikel, Poqomam, Mam
Early Postclassic 900–1200 CE Cholula, Tula, Mitla, El Tajín, Tulum, Topoxte, Kaminaljuyú, Joya de Cerén
Late Postclassic 1200–1521 CE Tenochtitlan, Cempoala, Tzintzuntzan, Mayapán, Ti'ho, Utatlán, Iximche, Mixco Viejo, Zaculeu
Colonial 1521-1821 Nahuas, Mayas, Mixtec, Zapotec, Purépecha, Chinantec, Otomi, Tepehua, Totonac, Mazatec, Tlapanec, Amuzgo
Postcolonial 1821-present Nahuas, Mayas, Mixtec, Zapotec, Purépecha, Chinantec, Otomi, Tepehua, Totonac, Mazatec, Tlapanec, Amuzgo

General characteristics

Subsistence

Examples of the diversity of maize

By roughly 6000 BC, hunter-gatherers living in the highlands and lowlands of Mesoamerica began to develop agricultural practices with early cultivation of squash and chilli. The earliest example of maize dates to c. 4000 BC and comes from Guilá Naquitz, a cave in Oaxaca. Earlier maize samples have been documented at the Los Ladrones cave site in Panama, c. 5500 BC.[19] Slightly thereafter, other crops began to be cultivated by the semi-agrarian communities throughout Mesoamerica.[20] Although maize is the most common domesticate, the common bean, tepary bean, scarlet runner bean, jicama, tomato and squash all became common cultivates by 3500 BC. At the same time, cotton, yucca and agave were exploited for fibers and textile materials.[21] By 2000 BC, corn 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 to assist in transportation 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, occurring around 3500 BC.[22] Dogs were the primary source of animal protein in ancient Mesoamerica,[23] and dog bones are common in midden deposits throughout the region.

Societies of this region did hunt certain wild species to complement their diet. These animals included deer, rabbit, birds, and various types of insects. They also hunted in order to gain luxury items such as feline fur and bird plumage.[24]

Mesoamerican cultures that lived in the lowlands and coastal plains settled down in agrarian communities somewhat later than did highland cultures due to the fact that there was a greater abundance of fruits and animals in these areas, which made a hunter-gatherer lifestyle more attractive.[25] Fishing also was a major provider of food to lowland and coastal Mesoamericans creating a further disincentive to settle down in permanent communities.

Political organization

K'inich Kan B'alam II, the Classic period ruler of Palenque, as depicted on a stele

Ceremonial centers were 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 himself with the city in which he lived.[citation needed]

The ceremonial centers were always built to be visible. The pyramids were meant to stand out from the rest of the city, to represent its gods and their powers. Another characteristic feature of the ceremonial centers is historic layers. All of 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 the veneration of their gods and masters.[citation needed] 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.

Economy

Given that Mesoamerica was broken into numerous and diverse ecological niches, none of the societies that inhabited the area were self-sufficient.[citation needed] For this reason, from the last centuries of the Archaic period 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 is a list of some of the specialized resources traded from the various Mesoamerican sub-regions and environmental contexts:

Common characteristics of Mesoamerican culture 

Calendrical systems

"Head Variant" or "Patron Gods" glyphs for Maya days
 
The emblem glyph of Tikal (Mutal)

Agriculturally based people historically divide the year into four seasons. These included the two solstices and the two equinoxes, which could be thought of as the four "directional pillars" that support the year. These four times of the year were, and still are, important as they indicate seasonal changes that directly impact the lives of Mesoamerican agriculturalists.

The Maya closely observed and duly recorded the seasonal markers. They prepared almanacs recording past and recent solar and lunar eclipses, the phases of the moon, the periods of Venus and Mars, the movements of various other planets, and conjunctions of celestial bodies. These almanacs also made future predictions concerning celestial events. These tables are remarkably accurate, given the technology available, and indicate a significant level of knowledge among Maya astronomers.[26]

Among the many types of calendars the Maya maintained, the most important include a 260-day cycle, a 360-day cycle or 'year', a 365-day cycle or year, a lunar cycle, and a Venus cycle, which tracked the synodic period of Venus. Maya of the European contact period said that knowing the past aided in both understanding the present and predicting the future (Diego de Landa). The 260-day cycle was a calendar to govern agriculture, observe religious holidays, mark the movements of celestial bodies and memorialize public officials. The 260-day cycle was also used for divination, and (like the Catholic calendar of saints) to name newborns.[27]

The names given to the days, months, and years in the Mesoamerican calendar came, for the most part, from animals, flowers, heavenly bodies, and cultural concepts that held symbolic significance in Mesoamerican culture. This calendar was used throughout the history of Mesoamerican by nearly every culture. Even today, several Maya groups in Guatemala, including the K'iche', Q'eqchi', Kaqchikel, and the Mixe people of Oaxaca continue using modernized forms of the Mesoamerican calendar.

Writing systems

One of the earliest examples of the Mesoamerican writing systems, the Epi-Olmec script on the La Mojarra Stela 1 dated to around AD 150. Mesoamerica is one of the five places in the world where writing has developed independently.

The Mesoamerican scripts deciphered to date are logosyllabic combining the use of logograms with a syllabary, and they are often called hieroglyphic scripts. Five or six different scripts have been documented in Mesoamerica, but archaeological dating methods, and a certain degree of self-interest, create difficulties in establishing priority and thus the forebear from which the others developed. The best documented and deciphered Mesoamerican writing system, and therefore the most widely known, is the classic Maya script. Others include the Olmec, Zapotec, and Epi-Olmec/Isthmian writing systems. An extensive Mesoamerican literature has been conserved partly in indigenous scripts and partly in the postinvasion transcriptions into Latin script.

The other glyphic writing systems of Mesoamerica, and their interpretation, have been subject to much debate. One important ongoing discussion regards whether non-Maya Mesoamerican texts can be considered examples of true writing or whether non-Maya Mesoamerican texts are best understood as pictographic conventions used to express ideas, specifically religious ones, but not representing the phonetics of the spoken language in which they were read.

Mesoamerican writing is found in several mediums, including large stone monuments such as stelae, carved directly onto architecture, carved or painted over stucco (e.g., murals), and on pottery. No Precolumbian Mesoamerican society is known to have had widespread literacy, and literacy was probably restricted to particular social classes, including scribes, painters, merchants, and the nobility.
The Mesoamerican book was typically written with brush and colored inks on a paper prepared from the inner bark of the ficus amacus. The book consisted of a long strip of the prepared bark, which was folded like a screenfold to define individual pages. The pages were often covered and protected by elaborately carved book boards. Some books were composed of square pages while others were composed of rectangular pages.

Following the Spanish conquests in the sixteenth century, Spanish friars taught indigenous scribes to write their languages in alphabetic texts. Many oral histories of the prehispanic period were subsequently recorded in alphabetic texts. The indigenous in central and southern Mexico continued to produce written texts in the colonial period, many with pictorial elements. An important scholarly reference work is the Handbook of Middle American Indians, Guide to Ethnohistorical Sources. Mesoamerican codices survive from the Aztec, Maya, Mixtec, and Zapotec regions.

Arithmetic

Mesoamerican arithmetic treated numbers as having both literal and symbolic value, the result of the dualistic nature that characterized Mesoamerican ideology.[citation needed] As mentioned, the Mesoamerican numbering system was vigesimal (i.e., based on the number 20).
In representing numbers, a series of bars and dots were employed. Dots had a value of one, and bars had a value of five. This type of arithmetic was combined with a symbolic numerology: '2' was related to origins, as all origins can be thought of as doubling; '3' was related to household fire; '4' was linked to the four corners of the universe; '5' expressed instability; '9' pertained to the underworld and the night; '13' was the number for light, '20' for abundance, and '400' for infinity. The concept of zero was also used, and its representation at the Late Preclassic occupation of Tres Zapotes is one of the earliest uses of zero in human history.

Food, medicine, and science


Maize played an important role in Mesoamerican feasts due to its symbolic meaning and abundance.[29]

Fray Bernardino de Sahagún collected extensive information on plants, animals, soil types, among other matters from native informants in Book 11, The Earthly Things, of the twelve-volume General History of the Things of New Spain, known as the Florentine Codex, compiled in the third quarter of the sixteenth century. An earlier work, the Badianus Manuscript or Libellus de Medicinalibus Indorum Herbis is another Aztec codex with written text and illustrations collected from the indigenous viewpoint.

Mythology and worldview

The xoloitzcuintle is one of the naguales of the god Quetzalcoatl. In this form, it helps the dead cross the Chicnahuapan, a river that separates the world of the living from the dead.

The shared traits in Mesoamerican mythology are characterized by their common basis as a religion that, although in many Mesoamerican groups developed into complex polytheistic religious systems, retained some shamanistic elements.[30]
 
Zapotec mask of the Bat God.

The great breadth of the Mesoamerican pantheon of deities is due to the incorporation of ideological and religious elements from the first primitive religion of Fire, Earth, Water and Nature. Astral divinities (the sun, stars, constellations, and Venus) were adopted and represented in anthropomorphic, zoomorphic, and anthropozoomorphic sculptures, and in day-to-day objects.[citation needed] The qualities of these gods and their attributes changed with the passage of time and with cultural influences from other Mesoamerican groups. The gods are at once three: creator, preserver, and destroyer, and at the same time just one. An important characteristic of Mesoamerican religion was the dualism among the divine entities. The gods represented the confrontation between opposite poles: the positive, exemplified by light, the masculine, force, war, the sun, etc.; and the negative, exemplified by darkness, the feminine, repose, peace, the moon, etc.

The typical Mesoamerican cosmology sees the world as separated into a day world watched by the sun and a night world watched by the moon. More importantly, the three superposed levels of the world are united by a Ceiba tree (Yaxche' in Mayan). The geographic vision is also tied to the cardinal points. Certain geographical features are linked to different parts of this cosmovision. Thus mountains and tall trees connect the middle and upper worlds; caves connect the middle and nether worlds.

Sacrifice

Generally, sacrifice can be divided into two types: autosacrifice and human sacrifice. The different forms of sacrifice are reflected in the imagery used to evoke ideological structure and sociocultural organization in Mesoamerica. In the Maya area, for example, stele depict bloodletting rituals performed by ruling elites, eagles and jaguars devouring human hearts, jade circles or necklaces that represented hearts, and plants and flowers that symbolized both nature and the blood that provided life.[citation needed] Imagery also showed pleas for rain or pleas for blood, with the same intention to replenish the divine energy.
Autosacrifice
Ritual human sacrifice portrayed in Codex Laud

Autosacrifice, also called bloodletting, is the ritualized practice of drawing blood from oneself. It is commonly seen or represented through iconography as performed by ruling elites in highly ritualized ceremonies, but it was easily practiced in mundane sociocultural contexts (i.e., non-elites could perform autosacrifice). The act was typically performed with obsidian prismatic blades or stingray spines, and blood was drawn from piercing or cutting the tongue, earlobes, and/or genitals (among other locations). Another form of autosacrifice was conducted by pulling a rope with attached thorns through the tongue or earlobes. The blood produced was then collected on paper held in a bowl.

Autosacrifice was not limited to male rulers, as their female counterparts often performed these ritualized activities. They are typically shown performing the rope and thorns technique. A recently discovered queen's tomb in the Classic Maya site of Waka (also known as El Perú) had a ceremonial stingray spine placed in her genital area, suggesting that women also performed bloodletting in their genitalia.[31]
Human sacrifice
Sacrifice had great importance in the social and religious aspects of Mesoamerican culture. First, it showed death transformed into the divine.[citation needed] Death is the consequence of a human sacrifice, but it is not the end; it is but the continuation of the cosmic cycle. Death creates life – divine energy is liberated through death and returns to the gods, who are then able to create more life. Secondly, it justifies war, since the most valuable sacrifices are obtained through conflict. The death of the warrior is the greatest sacrifice and gives the gods the energy to go about their daily activities, such as the bringing of rain. Warfare and capturing prisoners became a method of social advancement and a religious cause. Finally, it justifies the control of power by the two ruling classes, the priests and the warriors. The priests controlled the religious ideology, and the warriors supplied the sacrifices.

Ballgame

A small ceremonial ballcourt at Uaxactun.
 
Ballgame marker from the classic Lowland Maya site of Chinkultic, Mexico depicting a ballplayer in full gear

The Mesoamerican ballgame was a sport with ritual associations played for over 3000 years by nearly all pre-Columbian peoples of Mesoamerica. The sport had different versions in different places during the millennia, and a modern version of the game, ulama, continues to be played in a few places.

Over 1300 ballcourts have been found throughout Mesoamerica.[32] They vary considerably in size, but they all feature long narrow alleys with side-walls to bounce the balls against.

The rules of the ballgame are not known, but it was probably similar to volleyball, where the object is to keep the ball in play. In the most well-known version of the game, the players struck the ball with their hips, although some versions used forearms or employed rackets, bats, or handstones. The ball was made of solid rubber, and weighed up to 4 kg or more, with sizes that differed greatly over time or according to the version played.[33][34]

While the game was played casually for simple recreation, including by children and perhaps even women, the game also had important ritual aspects, and major formal ballgames were held as ritual events, often featuring human sacrifice.

Astronomy

Mesoamerican astronomy included a broad understanding of the cycles of planets and other celestial bodies. Special importance was given to the sun, moon, and Venus as the morning and evening star.

Observatories were built at some sites, including the round observatory at Ceibal and the “Observatorio” at Xochicalco. Often, the architectural organization of Mesoamerican sites was based on precise calculations derived from astronomical observations. Well-known examples of these include the El Castillo pyramid at Chichen Itza and the Observatorio at Xochicalco. A unique and common architectural complex found among many Mesoamerican sites are E-Groups, which are aligned so as to serve as astronomical observatories. The name of this complex is based on Uaxactun’s “Group E,” the first known observatory in the Maya area. Perhaps the earliest observatory documented in Mesoamerica is that of the Monte Alto culture. This complex consisted of three plain stelae and a temple oriented with respect to the Pleiades.

Symbolism of space and time

The Avenue of the Dead in Teotihuacan, an example of a Mesoamerican settlement planned according to concepts of directionality

It has been argued that among Mesoamerican societies the concepts of space and time are associated with the four cardinal compass points and linked together by the calendar.[35] Dates or events were always tied to a compass direction, and the calendar specified the symbolic geographical characteristic peculiar to that period. Resulting from the significance held by the cardinal directions, many Mesoamerican architectural features, if not entire settlements, were planned and oriented with respect to directionality.

In Maya cosmology, each cardinal point was assigned a specific color and a specific jaguar deity (Bacab). They are as follows:
  • Hobnil, Bacab of the East, associated with the color red and the Kan years
  • Can Tzicnal, Bacab of the North, assigned the color white and the Muluc years
  • 'Zac Cimi, Bacab of the West, associated with the color black and the Ix years
  • Hozanek, Bacab of the South, associated with the color yellow and the Cauac years.
Later cultures such as the Kaqchikel and K'iche' maintain the association of cardinal directions with each color, but utilized different names.

Among the Aztec, the name of each day was associated with a cardinal point (thus conferring symbolic significance), and each cardinal direction was associated with a group of symbols. Below are the symbols and concepts associated with each direction:
  • East: crocodile, the serpent, water, cane, and movement. The East was linked to the world priests and associated with vegetative fertility, or, in other words, tropical exuberance.
  • North: wind, death, the dog, the jaguar, and flint (or chert). The north contrasts with the east in that it is conceptualized as dry, cold, and oppressive. It is considered to be the nocturnal part of the universe and includes the dwellings of the dead. The dog (xoloitzcuintle) has a very specific meaning, as it accompanies the deceased during the trip to the lands of the dead and helps them cross the river of death that leads into nothingness. (See also Dogs in Mesoamerican folklore and myth).
  • West: the house, the deer, the monkey, the eagle, and rain. The west was associated with the cycles of vegetation, specifically the temperate high plains that experience light rains and the change of seasons.
  • South: rabbit, the lizard, dried herbs, the buzzard, and flowers. It is related on the one hand to the luminous Sun and the noon heat, and on the other with rain filled with alcoholic drink. The rabbit, the principal symbol of the west, was associated with farmers and with pulque.

Political and religious art

Art with ideological and political meaning: depiction of an Aztec tzompantli (skull-rack) from the Ramirez Codex

Mesoamerican artistic expression was conditioned by ideology and generally focused on themes of religion and/or sociopolitical power. This is largely based on the fact that most works that survived the Spanish conquest were public monuments. These monuments were typically erected by rulers who sought to visually legitimize their sociocultural and political position; by doing so, they intertwined their lineage, personal attributes and achievements, and legacy with religious concepts. As such, these monuments were specifically designed for public display and took many forms, including stele, sculpture, architectural reliefs, and other types of architectural elements (e.g., roofcombs). Other themes expressed include tracking time, glorifying the city, and veneration of the gods – all of which were tied to explicitly aggrandizing the abilities and the reign of the ruler who commissioned the artwork.
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An ultra-low-power artificial synapse for neural-network computing

Brain-like device with 500 states instead of binary could one day communicate with live neurons, merging computers with the brain
February 24, 2017
Original link:  http://www.kurzweilai.net/a-breakthrough-low-power-artificial-synapse-for-neural-network-computing
(Left) Illustration of a synapse in the brain connecting two neurons. (Right) Schematic of artificial synapse (ENODe), which functions as a transistor. It consists of two thin, flexible polymer films (black) with source, drain, and gate terminals, connected by an electrolyte of salty water that permits ions to cross. A voltage pulse applied to the “presynaptic” layer (top) alters the level of oxidation in the “postsynaptic layer” (bottom), triggering current flow between source and drain. (credit: Thomas Splettstoesser/CC and Yoeri van de Burgt et al./Nature Materials)

Stanford University and Sandia National Laboratories researchers have developed an organic artificial synapse based on a new memristor (resistive memory device) design that mimics the way synapses in the brain learn. The new artificial synapse could lead to computers that better recreate the way the human brain processes information. It could also one day directly interface with the human brain.

The new artificial synapse is an electrochemical neuromorphic organic device (dubbed “ENODe”) — a mixed ionic/electronic design that is fundamentally different from existing and other proposed resistive memory devices, which are limited by noise, required high write voltage, and other factors*, the researchers note in a paper published online Feb. 20 in Nature Materials.

Like a neural path in a brain being reinforced through learning, the artificial synapse is programmed by discharging and recharging it repeatedly. Through this training, the researchers have been able to predict within 1 percent of uncertainly what voltage will be required to get the synapse to a specific electrical state and, once there, remain at that state.

“The working mechanism of ENODes is reminiscent of that of natural synapses, where neurotransmitters diffuse through the cleft, inducing depolarization due to ion penetration in the postsynaptic neuron,” the researchers explain in the paper. “In contrast, other memristive devices switch by melting materials at relatively high temperatures (PCMs) or by voltage-induced breakdown/filament formation and ion diffusion in dense oxide layers (FFMOs).”

The ENODe achieves significant energy savings** in two ways:
  • Unlike a conventional computer, where you save your work to the hard drive before you turn it off, the artificial synapse can recall its programming without any additional actions or parts. Traditional computing requires separately processing information and then storing it into memory. Here, the processing creates the memory.
  • When we learn, electrical signals are sent between neurons in our brain. The most energy is needed the first time a synapse is traversed. Every time afterward, the connection requires less energy. This is how synapses efficiently facilitate both learning something new and remembering what we’ve learned. The artificial synapse, unlike most other versions of brain-like computing, also fulfills these two tasks simultaneously, and does so with substantial energy savings.
“More and more, the kinds of tasks that we expect our computing devices to do require computing that mimics the brain because using traditional computing to perform these tasks is becoming really power hungry,” said A. Alec Talin, distinguished member of technical staff at Sandia National Laboratories in Livermore, California, and co-senior author of the paper. “We’ve demonstrated a device that’s ideal for running these type of algorithms and that consumes a lot less power.”

A future brain-like computer with 500 states


Only one artificial synapse has been produced so far, but researchers at Sandia used 15,000 measurements to simulate how an array of them would work in a neural network. They tested the simulated network’s ability to recognize handwriting of digits 0 through 9. Tested on three datasets, the simulated array was able to identify the handwritten digits with an accuracy between 93 to 97 percent.

This artificial synapse may one day be part of a brain-like computer, which could be especially useful for processing visual and auditory signals, as in voice-controlled interfaces and driverless cars, but without energy-consuming computer hardware.

This device is also well suited for the kind of signal identification and classification that traditional computers struggle to perform. Whereas digital transistors can be in only two states, such as 0 and 1, the researchers successfully programmed 500 states in the artificial synapse, which is useful for neuron-type computation models. In switching from one state to another they used about one-tenth as much energy as a state-of-the-art computing system needs to move data from the processing unit to the memory.

However, this is still about 10,000 times as much energy as the minimum a biological synapse needs in order to fire**. The researchers hope to attain neuron-level energy efficiency once they test the artificial synapse in smaller devices.

Linking to live organic neurons


This new artificial synapse may one day be part of a brain-like computer, which could be especially beneficial for computing that works with visual and auditory signals. Examples of this are seen in voice-controlled interfaces and driverless cars. Past efforts in this field have produced high-performance neural networks supported by artificially intelligent algorithms but these depend on energy-consuming traditional computer hardware.

Every part of the device is made of inexpensive organic materials. These aren’t found in nature but they are largely composed of hydrogen and carbon and are compatible with the brain’s chemistry. Cells have been grown on these materials and they have even been used to make artificial pumps for neural transmitters. The switching voltages applied to train the artificial synapse (about 0.5 mV) are also the same as those that move through human neurons — about 1,000 times lower than the “write” voltage for a typical memristor.

That means it’s possible that the artificial synapse could communicate with live neurons, leading to improved brain-machine interfaces. The softness and flexibility of the device also lends itself to being used in biological environments.

This research was funded by the National Science Foundation, the Keck Faculty Scholar Funds, the Neurofab at Stanford, the Stanford Graduate Fellowship, Sandia’s Laboratory-Directed Research and Development Program, the U.S. Department of Energy, the Holland Scholarship, the University of Groningen Scholarship for Excellent Students, the Hendrik Muller National Fund, the Schuurman Schimmel-van Outeren Foundation, the Foundation of Renswoude (The Hague and Delft), the Marco Polo Fund, the Instituto Nacional de Ciência e Tecnologia/Instituto Nacional de Eletrônica Orgânica in Brazil, the Fundação de Amparo à Pesquisa do Estado de São Paulo and the Brazilian National Council.

* “A resistive memory device has not yet been demonstrated with adequate electrical characteristics to fully realize the efficiency and performance gains of a neural architecture. State-of-the-art memristors suffer from excessive write noise, write non-linearities, and high write voltages and currents.  Reducing the noise and lowering the switching voltage significantly below 0.3 V (~10 kT) in a two-terminal device without compromising long-term data retention has proven difficult.” … Organic memristive devices have been recently proposed, but are limited by “the slow kinetics of ion diffusion through a polymer to retain their states or on charge storage in metal nanoparticles, which inherently limits performance and stability.” — Yoeri van de Burgt et al., Nature Materials
 
** ENODe switches at low voltage and energy (< 10 pJ for 1000-square-micrometer devices), compared to an estimated ∼ 1–100 fJ per synaptic event for the human brain.
 

Abstract of A non-volatile organic electrochemical device as a low-voltage artificial synapse for neuromorphic computing

The brain is capable of massively parallel information processing while consuming only ~1–100 fJ per synaptic event. Inspired by the efficiency of the brain, CMOS-based neural architectures and memristors are being developed for pattern recognition and machine learning. However, the volatility, design complexity and high supply voltages for CMOS architectures, and the stochastic and energy-costly switching of memristors complicate the path to achieve the interconnectivity, information density, and energy efficiency of the brain using either approach. Here we describe an electrochemical neuromorphic organic device (ENODe) operating with a fundamentally different mechanism from existing memristors. ENODe switches at low voltage and energy (<10 10="" for="" pj="" sup="">3
μm2 devices), displays >500 distinct, non-volatile conductance states within a ~1 V range, and achieves high classification accuracy when implemented in neural network simulations. Plastic ENODes are also fabricated on flexible substrates enabling the integration of neuromorphic functionality in stretchable electronic systems. Mechanical flexibility makes ENODes compatible with three-dimensional architectures, opening a path towards extreme interconnectivity comparable to the human brain.

References:

Related:

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Indigenous peoples in Brazil

From Wikipedia, the free encyclopedia
Indigenous peoples in Brazil
Povos Indígenas no Brasil
Total population
896,917
0.6% of Brazil's population[1]
Regions with significant populations
Predominantly in the North and Central-West
Languages
Indigenous languages, Portuguese
Religion
61.1% Roman Catholic, 19.9% Protestant, 11% non-religious, 8% other beliefs[2]
Related ethnic groups
Other Indigenous peoples of the Americas
Indigenous girl of Terena tribe

Indigenous peoples in Brazil (Portuguese: povos indígenas no Brasil), or Indigenous Brazilians (Portuguese: indígenas brasileiros), comprise a large number of distinct ethnic groups who have inhabited what is now the country of Brazil since prior to the European contact around 1500. Unlike Christopher Columbus, who thought he had reached the East Indies, the Portuguese, most notably Vasco da Gama, had already reached India via the Indian Ocean route when they reached Brazil.

Nevertheless, the word índios ("Indians") was by then established to designate the people of the New World and continues to be used today in the Portuguese language to designate these people, while a person from India is called indiano in order to distinguish the two.

At the time of European contact, some of the indigenous people were traditionally mostly semi-nomadic tribes who subsisted on hunting, fishing, gathering, and migrant agriculture. Many of the estimated 2,000 nations and tribes which existed in the 16th century suffered extinction as a consequence of the European settlement, and many were assimilated into the Brazilian population.
The indigenous population was largely killed by European diseases, declining from a pre-Columbian high of millions to some 300,000 (1997), grouped into 200 tribes. However, the number could be much higher if the urban indigenous populations are counted in all the Brazilian cities today. A somewhat dated linguistic survey[3] found 188 living indigenous languages with 155,000 total speakers.

On January 18, 2007, FUNAI reported that it had confirmed the presence of 67 different uncontacted tribes in Brazil, up from 40 in 2005. With this addition, Brazil has now surpassed New Guinea as the country having the largest number of uncontacted peoples in the world.[4]

In the last IBGE census (2010), 817,000 Brazilians classified themselves as indigenous.

Origins

Xingu, an indigenous territory of Brazil

Questions about the original settlement of the Americas has produced a number of hypothetical models. The origins of these indigenous people are still a matter of dispute among archaeologists.[5]

Migration into the continents

Anthropological and genetic evidence indicates that most Amerindian people descended from migrant people from North Asia (Siberia) who entered the Americas across the Bering Strait or along the western coast of North America in at least three separate waves. In Brazil, particularly, most native tribes who were living in the land by 1500 are thought to be descended from the first Siberian wave of migrants, who are believed to have crossed the Bering Land Bridge at the end of the last Ice Age, between 13,000 and 17,000 years before the present. A migrant wave would have taken some time after initial entry to reach present-day Brazil, probably entering the Amazon River basin from the Northwest. (The second and third migratory waves from Siberia, which are thought to have generated the Athabaskan, Aleut, Inuit, and Yupik people, apparently did not reach farther than the southern United States and Canada, respectively).[6]

An analysis of Amerindian Y-chromosome DNA indicates specific clustering of much of the South American population. The micro-satellite diversity and distributions of the Y lineage specific to South America indicates that certain Amerindian populations have been isolated since the initial colonization of the region.[7]

Genetic studies

Apiacá people, painted by Hércules Florence, 1827

According to an autosomal genetic study from 2012,[8] Native Americans descend from at least three main migrant waves from East Asia. Most of it is traced back to a single ancestral population, called 'First Americans'. However, those who speak Inuit languages from the Arctic inherited almost half of their ancestry from a second East Asian migrant wave. And those who speak Na-dene, on the other hand, inherited a tenth of their ancestry from a third migrant wave. The initial settling of the Americas was followed by a rapid expansion southwards, by the coast, with little gene flow later, especially in South America. One exception to this are the Chibcha speakers, whose ancestry comes from both North and South America. [8]

Another study, focused on the mtDNA (that which is inherited only through the maternal line),[9] revealed that the indigenous people of the Americas have their maternal ancestry traced back to a few founding lineages from East Asia, which would have arrived via the Bering strait. According to this study, it is probable that the ancestors of the Native Americans would have remained for a time in the region of the Bering Strait, after which there would have been a rapid movement of settling of the Americas, taking the founding lineages to South America.

Linguistic studies have backed up genetic studies, with ancient patterns having been found between the languages spoken in Siberia and those spoken in the Americas.[10]

Two 2015 autosomal DNA genetic studies confirmed the Siberian origins of the Natives of the Americas. However an ancient signal of shared ancestry with the Natives of Australia and Melanesia was detected among the Natives of the Amazon region. The migration coming out of Siberia would have happened 23,000 years ago.[11][12][13]

According to a 2016 study, focused on mtDNA lineages, "a small population entered the Americas via a coastal route around 16.0 ka, following previous isolation in eastern Beringia for ~2.4 to 9 thousand years after separation from eastern Siberian populations. Following a rapid movement throughout the Americas, limited gene flow in South America resulted in a marked phylogeographic structure of populations, which persisted through time. All of the ancient mitochondrial lineages detected in this study were absent from modern data sets, suggesting a high extinction rate. To investigate this further, we applied a novel principal components multiple logistic regression test to Bayesian serial coalescent simulations. The analysis supported a scenario in which European colonization caused a substantial loss of pre-Columbian lineages".[14]

Archaeological remains

Terena people

Brazilian native people, unlike those in Mesoamerica and the western Andes, did not keep written records or erect stone monuments, and the humid climate and acidic soil have destroyed almost all traces of their material culture, including wood and bones. Therefore, what is known about the region's history before 1500 has been inferred and reconstructed from small-scale archaeological evidence, such as ceramics and stone arrowheads.

The most conspicuous remains of these societies are very large mounds of discarded shellfish (sambaquis) found in some coastal sites which were continuously inhabited for over 5,000 years; and the substantial "black earth" (terra preta) deposits in several places along the Amazon, which are believed to be ancient garbage dumps (middens). Recent excavations of such deposits in the middle and upper course of the Amazon have uncovered remains of some very large settlements, containing tens of thousands of homes, indicating a complex social and economic structure.[15]

Marajoara culture

Marajoara culture flourished on Marajó island at the mouth of the Amazon River.[16] Archeologists have found sophisticated pottery in their excavations on the island. These pieces are large, and elaborately painted and incised with representations of plants and animals. These provided the first evidence that a complex society had existed on Marajó. Evidence of mound building further suggests that well-populated, complex and sophisticated settlements developed on this island, as only such settlements were believed capable of such extended projects as major earthworks.[17]
The extent, level of complexity, and resource interactions of the Marajoara culture have been disputed. Working in the 1950s in some of her earliest research, American Betty Meggers suggested that the society migrated from the Andes and settled on the island. Many researchers believed that the Andes were populated by Paleoindian migrants from North America who gradually moved south after being hunters on the plains.

In the 1980s, another American archeologist, Anna Curtenius Roosevelt, led excavations and geophysical surveys of the mound Teso dos Bichos. She concluded that the society that constructed the mounds originated on the island itself.[18]

The pre-Columbian culture of Marajó may have developed social stratification and supported a population as large as 100,000 people.[16] The Native Americans of the Amazon rain forest may have used their method of developing and working in Terra preta to make the land suitable for the large-scale agriculture needed to support large populations and complex social formations such as chiefdoms.[16]

Native people after the European colonization

Distribution

Distribution of Tupi and Tapuia people on the coast of Brazil, on the eve of colonialism in the 16th century

On the eve of the Portuguese arrival in 1500, the coastal areas of Brazil had two major mega-groups - the Tupi (speakers of Tupi–Guarani languages), who dominated practically the entire length of the Brazilian coast, and the Tapuia (a catch-all term for non-Tupis, usually Jê language people), who resided primarily in the interior. The Portuguese arrived in the final days of a long pre-colonial struggle between Tupis and Tapuias, which had resulted in the defeat and expulsion of the Tapuias from most coastal areas.

Although the coastal Tupi were broken down into sub-tribes, frequently hostile to each other, they were culturally and linguistically homogeneous. The fact that the early Europeans encountered practically the same people and language all along the Brazilian coast greatly simplified early communication and interaction.

Coastal Sequence c. 1500 (north to south):[19]
  1. Tupinambá (Tupi, from the Amazon delta to Maranhão)
  2. Tremembé (Tapuia, coastal tribe, ranged from São Luis Island (south Maranhão) to the mouth of the Acaraú River in north Ceará; French traders cultivated an alliance with them)
  3. Potiguara (Tupi, literally "shrimp-eaters"; they had a reputation as great canoeists and aggressively expansionist, inhabited a great coastal stretch from Acaraú River to Itamaracá island, covering the modern states of southern Ceará, Rio Grande do Norte and Paraíba.)
  4. Tabajara (tiny Tupi tribe between Itamaracá island and Paraiba River; neighbors and frequent victims of the Potiguara)
  5. Caeté (Tupi group in Pernambuco, ranged from Paraiba River to the São Francisco River; after killing and eating a Portuguese bishop, they were subjected to Portuguese extermination raids and the remnant pushed into the Pará interior)
  6. Tupinambá again (Tupi par excellence, ranged from the São Francisco River to the Bay of All Saints, population estimated as high as 100,000; hosted Portuguese castaway Caramuru)
  7. Tupiniquim (Tupi, covered Bahian discovery coast, from around Camamu to São Mateus River; these were the first indigenous people encountered by the Portuguese, having met the landing of captain Pedro Álvares Cabral in April 1500)
  8. Aimoré (Tapuia (Jê) tribe; concentrated on a sliver of coast in modern Espírito Santo state)
  9. Goitacá (Tapuia tribe; once dominated the coast from São Mateus River (in Espírito Santo state) down to the Paraíba do Sul river (in Rio de Janeiro state); hunter-gatherers and fishermen, they were a shy people that avoided all contact with foreigners; estimated at 12,000; they had a fearsome reputation and were eventually annihilated by European colonists)
  10. Temiminó (small Tupi tribe, centered on Governador Island in Guanabara Bay; frequently at war with the Tamoio around them)
  11. Tamoio (Tupi, old branch of the Tupinambá, ranged from the western edge of Guanabara bay to Ilha Grande)
  12. Tupinambá again (Tupi, indistinct from the Tamoio. Inhabited the Paulist coast, from Ilha Grande to Santos; main enemies of the Tupiniquim to their west. Numbered between six and ten thousand).
  13. Tupiniquim again (Tupi, on the São Paulo coast from Santos/Bertioga down to Cananéia; aggressively expansionist, they were recent arrivals imposing themselves on the Paulist coast and the Piratininga plateau at the expense of older Tupinambá and Carijó neighbors; hosted Portuguese castaways João Ramalho ('Tamarutaca') and António Rodrigues in the early 1500s; the Tupiniquim were the first formal allies of the Portuguese colonists, helped establish the Portuguese Captaincy of São Vicente in the 1530s; sometimes called "Guaianá" in old Portuguese chronicles, a Tupi term meaning "friendly" or "allied")
  14. Carijó (Guarani (Tupi) tribe, ranged from Cananeia all the way down to Lagoa dos Patos (in Rio Grande do Sul state); victims of the Tupiniquim and early European slavers; they hosted the mysterious degredado known as the 'Bachelor of Cananeia')
  15. Charrúa (Tapuia (Jê) tribe in modern Uruguay coast, with an aggressive reputation against intruders; killed Juan Díaz de Solís in 1516)
With the exception of the hunter-gatherer Goitacases, the coastal Tupi and Tapuia tribes were primarily agriculturalists. The subtropical Guarani cultivated maize, tropical Tupi cultivated manioc (cassava), highland Jês cultivated peanut, as the staple of their diet. Supplementary crops included beans, sweet potatoes, cará (yam), jerimum (pumpkin), and cumari (capsicum pepper).

Behind these coasts, the interior of Brazil was dominated primarily by Tapuia (Jê) people, although significant sections of the interior (notably the upper reaches of the Xingu, Teles Pires and Juruena Rivers - the area now covered roughly by modern Mato Grosso state) were the original pre-migration Tupi-Guarani homelands. Besides the Tupi and Tapuia, it is common to identify two other indigenous mega-groups in the interior: the Caribs, who inhabited much of what is now northwestern Brazil, including both shores of the Amazon River up to the delta and the Nuaraque group, whose constituent tribes inhabited several areas, including most of the upper Amazon (west of what is now Manaus) and also significant pockets in modern Amapá and Roraima states.

The names by which the different Tupi tribes were recorded by Portuguese and French authors of the 16th century are poorly understood. Most do not seem to be proper names, but descriptions of relationship, usually familial - e.g. tupi means "first father", tupinambá means "relatives of the ancestors", tupiniquim means "side-neighbors", tamoio means "grandfather", temiminó means "grandson", tabajara means "in-laws" and so on.[20] Some etymologists believe these names reflect the ordering of the migration waves of Tupi people from the interior to the coasts, e.g. first Tupi wave to reach the coast being the "grandfathers" (Tamoio), soon joined by the "relatives of the ancients" (Tupinamba), by which it could mean relatives of the Tamoio, or a Tamoio term to refer to relatives of the old Tupi back in the upper Amazon basin. The "grandsons" (Temiminó) might be a splinter. The "side-neighbors" (Tupiniquim) meant perhaps recent arrivals, still trying to jostle their way in. However, by 1870 the Tupi tribes population had declined to 250,000 indígenas and by 1890 had diminished to an approximate 100,000 tribes.
Native Brazilian Population in Northeast Coast (Dutch estimatives).[21]
Period Total
1540 +100,000
1640 9,000

First contacts

Depiction of cannibalism in the Brazilian Tupinambá tribe, as described by Hans Staden.
Albert Eckhout (Dutch), Tapuias (Brazil) dancing, 17th c.

When the Portuguese explorers first arrived in Brazil in April 1500, they found, to their astonishment, a wide coastline rich in resources, teeming with hundreds of thousands of Indigenous people living in a "paradise" of natural riches. Pêro Vaz de Caminha, the official scribe of Pedro Álvares Cabral, the commander of the discovery fleet which landed in the present state of Bahia, wrote a letter to the King of Portugal describing in glowing terms the beauty of the land.

At the time of European arrival, the territory of current day Brazil had as many as 2,000 nations and tribes. The indigenous people were traditionally mostly semi-nomadic tribes who subsisted on hunting, fishing, gathering, and migrant agriculture. For hundreds of years, the indigenous people of Brazil lived a semi-nomadic life, managing the forests to meet their needs. When the Portuguese arrived in 1500, the natives were living mainly on the coast and along the banks of major rivers. Initially, the Europeans saw native people as noble savages, and miscegenation of the population began right away. Portuguese claims of tribal warfare, cannibalism, and the pursuit of Amazonian brazilwood for its treasured red dye convinced the Portuguese that they should "civilize" the natives (originally, colonists called Brazil Terra de Santa Cruz, until later it acquired its name (see List of meanings of countries' names) from brazilwood). But the Portuguese, like the Spanish in their North American territories, had brought diseases with them against which many Indians were helpless due to lack of immunity. Measles, smallpox, tuberculosis, and influenza killed tens of thousands. The diseases spread quickly along the indigenous trade routes, and it is likely that whole tribes were annihilated without ever coming in direct contact with Europeans.

Slavery and the bandeiras

Brazilian Indians during a ritual, Debret

The mutual feeling of wonderment and good relationship was to end in the succeeding years. The Portuguese colonists, all males, started to have children with female Amerindians, creating a new generation of mixed-race people who spoke Indian languages (a Tupi language called Nheengatu). The children of these Portuguese men and Indian women formed the majority of the population. Groups of fierce pathfinders organized expeditions called "bandeiras" (flags) into the backlands to claim them for the Portuguese crown and to look for gold and precious stones.

Intending to profit from sugar trade, the Portuguese decided to plant sugar cane in Brazil, and to use indigenous slaves as the workforce, as the Spanish colonies were successfully doing. But the indigenous people were hard to capture. They were soon infected by diseases brought by the Europeans against which they had no natural immunity, and began dying in great numbers.

The Jesuits: Protectors of the Indians

Map of indigenous territories in Brazil.

The Jesuit priests, who had come with the first Governor General to provide religious assistance to the colonists, but mainly to convert the Pagan people to Catholicism, took the side of the Indians and extracted a Papal bull stating that they were human and should be protected.

Jesuit priests such as fathers José de Anchieta and Manuel da Nóbrega studied and recorded their language and founded mixed settlements, such as São Paulo dos Campos de Piratininga, where colonists and Indians lived side by side, speaking the same Língua Geral (common language) and freely intermarried. They began also to establish more remote villages peopled only by "civilized" Indians, called Missions, or reductions (see the article on the Guarani people for more details).

By the middle of the 16th century, Catholic Jesuit priests, at the behest of Portugal's monarchy, had established missions throughout the country's colonies. They became protectors of the Indians and worked to both Europeanize them and convert them to Catholicism. The Jesuits provided a period of relative stability for the Indians.

In the mid-1770s, the Indians' fragile co-existence with the colonists was again threatened. Because of a complex diplomatic web between Portugal, Spain and the Vatican, the Jesuits were expelled from Brazil and the missions confiscated and sold.

By 1800, the population of Brazil had reached approximately 3.25 million, of which only 250,000 were indigenous. And for the next four decades, the Indians were largely left alone.

Wars

A Tamoio Warrior depicted by Jean-Baptiste Debret in the early 19th century.

A number of wars between several tribes, such as the Tamoio Confederation, and the Portuguese ensued, sometimes with the Indians siding with enemies of Portugal, such as the French, in the famous episode of France Antarctique in Rio de Janeiro, sometimes allying themselves to Portugal in their fight against other tribes. At approximately the same period, a German soldier, Hans Staden, was captured by the Tupinambá and released after a while. He described it in a famous book, Warhaftige Historia und beschreibung eyner Landtschafft der Wilden Nacketen, Grimmigen Menschfresser-Leuthen in der Newenwelt America gelegen (True Story and Description of a Country of Wild, Naked, Grim, Man-eating People in the New World, America) (1557)

There are various documented accounts of smallpox being knowingly used as a biological weapon by New Brazilian villagers that wanted to get rid of nearby Indian tribes (not always aggressive ones). The most "classical", according to Anthropologist, Mércio Pereira Gomes, happened in Caxias, in south Maranhão, where local farmers, wanting more land to extend their cattle farms, gave clothing owned by ill villagers (that normally would be burned to prevent further infection) to the Timbira. The clothing infected the entire tribe, and they had neither immunity nor cure. Similar things happened in other villages throughout South America.[22]

The rubber trade

The 1840s brought trade and wealth to the Amazon. The process for vulcanizing rubber was developed, and worldwide demand for the product skyrocketed. The best rubber trees in the world grew in the Amazon, and thousands of rubber tappers began to work the plantations. When the Indians proved to be a difficult labor force, peasants from surrounding areas were brought into the region. In a dynamic that continues to this day, the indigenous population was at constant odds with the peasants, who the Indians felt had invaded their lands in search of treasure.

The legacy of Cândido Rondon

Marshal Cândido Rondon.

In the 20th century, the Brazilian Government adopted a more humanitarian attitude and offered official protection to the indigenous people, including the establishment of the first indigenous reserves. Fortune brightened for the Indians around the turn of the 20th century when Cândido Rondon, a man of both Portuguese and Bororo ancestry, and an explorer and progressive officer in the Brazilian army, began working to gain the Indians' trust and establish peace. Rondon, who had been assigned to help bring telegraph communications into the Amazon, was a curious and natural explorer. In 1910, he helped found the Serviço de Proteção aos Índios - SPI (Service for the Protection of Indians, today the FUNAI, or Fundação Nacional do Índio, National Foundation for Indians). SPI was the first federal agency charged with protecting Indians and preserving their culture. In 1914, Rondon accompanied Theodore Roosevelt on Roosevelt's famous expedition to map the Amazon and discover new species. During these travels, Rondon was appalled to see how settlers and developers treated the indigenes, and he became their lifelong friend and protector.

Rondon, who died in 1958, is a national hero in Brazil. The Brazilian state of Rondônia is named after him.

SPI failure and FUNAI

Tapirapé woman painting the body.

After Rondon's pioneering work, the SPI was turned over to bureaucrats and military officers and its work declined after 1957. The new officials did not share Rondon's deep commitment to the Indians. SPI sought to address tribal issues by transforming the tribes into mainstream Brazilian society. The lure of reservation riches enticed cattle ranchers and settlers to continue their assault on Indians lands – and the SPI eased the way. Between 1900 and 1967, an estimated 98 indigenous tribes were wiped out.[citation needed]

Mostly due to the efforts of the Villas-Bôas brothers, Brazil's first Indian reserve, the Xingu National Park, was established by the Federal Government in 1961.

During the social and political upheaval in the 1960s, reports of mistreatment of Indians increasingly reached Brazil's urban centers and began to affect Brazilian thinking. In 1967, following the publication of the Figueiredo Report, commissioned by the Ministry of the Interior, the military government launched an investigation into SPI. It soon came to light that the SPI was corrupt and failing to protect natives, their lands, and, culture. The 5,000-page report catalogued atrocities including slavery, sexual abuse, torture, and mass murder.[23] It has been charged that agency officials, in collaboration with land speculators, were systematically slaughtering the Indians by intentionally circulating disease-laced clothes.[citation needed] Criminal prosecutions followed, and the SPI was disbanded. The same year the government established Fundação Nacional do Índio (National Indian Foundation), known as FUNAI which is responsible for protecting the interests, cultures, and rights of the Brazilian indigenous populations. Some tribes have become significantly integrated into Brazilian society. The unacculturated tribes which have been contacted by FUNAI, are supposed to be protected and accommodated within Brazilian society in varying degrees. By 1987 it was recognized that unessential contact with the tribes was causing illness and social disintegration. The uncontacted tribes are now supposed to be protected from intrusion and interference in their life style and territory.[23] However, the exploitation of rubber and other Amazonic natural resources has led to a new cycle of invasion, expulsion, massacres and death, which continues to this day.[citation needed]

The military government

Also in 1964, in a seismic political shift, the Brazilian military took control of the government and abolished all existing political parties, creating a two-party system. For the next two decades, Brazil was ruled by a series of generals. The country's mantra was "Brazil, the Country of the Future," which the military government used as justification for a giant push into the Amazon to exploit its resources, thereby beginning to transform Brazil into one of the leading economies of the world. Construction began on a transcontinental highway across the Amazon basin, aimed to encourage migration to the Amazon and to open up the region to more trade. With funding from World Bank, thousands of square miles of forest were cleared without regard for reservation status. After the highway projects came giant hydroelectric projects, then swaths of forest were cleared for cattle ranches. As a result, reservation lands suffered massive deforestation and flooding. The public works projects attracted very few migrants, but those few – and largely poor - settlers brought new diseases that further devastated the Indians population.

Contemporary situation

Members of an uncontacted tribe encountered in the Brazilian state of Acre in 2009

The 1988 Brazilian Constitution recognises indigenous people' right to pursue their traditional ways of life and to the permanent and exclusive possession of their "traditional lands", which are demarcated as Indigenous Territories.[24] In practice, however, Brazil's indigenous people still face a number of external threats and challenges to their continued existence and cultural heritage.[25] The process of demarcation is slow—often involving protracted legal battles—and FUNAI do not have sufficient resources to enforce the legal protection on indigenous land.[26][25][27][28][29] Since the 1980s there has been a boom in the exploitation of the Amazon Rainforest for mining, logging and cattle ranching, posing a severe threat to the region's indigenous population. Settlers illegally encroaching on indigenous land continue to destroy the environment necessary for indigenous people' traditional ways of life, provoke violent confrontations and spread disease.[25] people such as the Akuntsu and Kanoê have been brought to the brink of extinction within the last three decades.[30][31] On 13 November 2012, the national indigenous people association from Brazil APIB submitted to the United Nation a human rights document that complaints about new proposed laws in Brazil that would further undermine their rights if approved.[4]

Much of the language has been incorporated into the official Brazilian Portuguese language. For example, 'Carioca' the word used to describe people born in the city of Rio de Janeiro, is from the indigenous word for 'house of the white (people)'[32].

Indigenous Rights Movements

Urban Rights Movement

The urban rights movement is a recent development in the rights of indigenous peoples. Brazil has one of the highest income inequalities in the world,[33] and much of that population includes indigenous tribes migrating toward urban areas both by choice and by displacement. Beyond the urban rights movement, studies have shown that the suicide risk among the indigenous population is 8.1 times higher than the non-indigenous population.[34]

Many indigenous rights movements have been created through the meeting of many indigenous tribes in urban areas. For example, in Barcelos, an indigenous rights movement arose because of "local migratory circulation.[35]" This is how many alliances form to create a stronger network for mobilization. Indigenous populations also living in urban areas have struggles regarding work. They are pressured into doing cheap labor.[36] Programs like Oxfam have been used to help indigenous people gain partnerships to begin grassroots movements.[37] Some of their projects overlap with environmental activism as well.

Many Brazilian youths are mobilizing through the increased social contact, since some indigenous tribes stay isolated while others adapt to the change.[38] Access to education also affects these youths, and therefore, more groups are mobilizing to fight for indigenous rights.

Environmental and Territorial Rights Movement

Much of Indigenous tribes' rights parallel the environmental and territorial rights movement. Although indigenous people have gained 21% of the Brazilian Amazon as part of indigenous land, there are many issues still today that affect the sustainability of Indigenous territories today.[39] Environmentalists and indigenous peoples have been viewed as opponents to economic growth and barriers to development[40] due to the fact that much of the land that indigenous tribes live on could be used for development projects and more industrialization. Currently, 15% of global greenhouse gas emissions can be attributed to forest clearing and degradation. Deforestation for mining also affects the daily lives of indigenous tribes in Brazil.[41] The Munduruku Indians have higher levels of mercury poisoning due to gold production in the area.[42] Climate change is one issue that indigenous tribes attribute as a reason to keep their territory.

There are a lot of alliances between indigenous peoples and conservation organizations in the Brazilian Amazon.The A'ukre Kayapo village and the Instituto SocioAmbiental (ISA) environmental organization is a good example of one of these alliances. They focus on environmental, education and developmental rights.[43] For example, Amazon Watch collaborates with various indigenous organizations in Brazil to fight for both territorial and environmental rights.[44] "Access to natural resources by indigenous and peasant communities in Brazil has been considerably less and much more insecure,[45]" so activists focus on more traditional conservation efforts, and expanding territorial rights for indigenous people.

Territorial rights for the indigenous populations of Brazil largely fall under socio-economic issues. There have been violent conflicts regarding rights to land between the government and the indigenous population,[41] and political rights have done little to stop them. There have been movements of the landless (MST) that helps keep land away from the elite living in Brazil.
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Neural networks promise sharpest-ever telescope images

May improve existing and future images of the TRAPPIST-1 exoplanets recently discovered by NASA
February 27, 2017
Original link:  http://www.kurzweilai.net/neural-networks-promise-sharpest-ever-images
From left to right: an example of an original galaxy image; the same image deliberately degraded; the image after recovery by the neural network; and for comparison, deconvolution. This figure visually illustrates the neural-networks’s ability to recover features that conventional deconvolutions cannot. (credit: K. Schawinski / C. Zhang / ETH Zurich)

Swiss researchers are using neural networks to achieve the sharpest-ever images in optical astronomy. The work appears in an open-access paper in Monthly Notices of the Royal Astronomical Society.
The aperture (diameter) of any telescope is fundamentally limited by its lens or mirror. The bigger the mirror or lens, the more light it gathers, allowing astronomers to detect fainter objects, and to observe them more clearly. Other factors affecting image quality are noise and atmospheric distortion.

The Swiss study uses “generative adversarial network” (GAN) machine-learning technology (see this KurzweilAI article) to go beyond this limit by using two neural networks that compete with each other to create a series of more realistic images. The researchers first train the neural network to “see” what galaxies look like (using blurred and sharp images of the same galaxy), and then ask it to automatically fix the blurred images of a galaxy, converting them to sharp ones.

Schematic illustration of the neural-network training process. The input is a set of original images. From these, the researchers automatically generate degraded images, and train a GAN. In the testing phase, only the generator will be used to recover images. (credit: K. Schawinski / C. Zhang / ETH Zurich)

The trained neural networks were able to recognize and reconstruct features that the telescope could not resolve, such as star-forming regions and dust lanes in galaxies. The scientists checked the reconstructed images against the original high-resolution images to test its performance, finding it better able to recover features than anything used to date.

“We can start by going back to sky surveys made with telescopes over many years, see more detail than ever before, and, for example, learn more about the structure of galaxies,” said lead author Prof. Kevin Schawinski of ETH Zurich in Switzerland. “There is no reason why we can’t then apply this technique to the deepest images from Hubble, and the coming James Webb Space Telescope, to learn more about the earliest structures in the Universe.”

ETH Zurich is hosting this work on the space.ml cross-disciplinary astrophysics/computer-science initiative, where the code is available to the general public.


Abstract of Generative adversarial networks recover features in astrophysical images of galaxies beyond the deconvolution limit

Observations of astrophysical objects such as galaxies are limited by various sources of random and systematic noise from the sky background, the optical system of the telescope and the detector used to record the data. Conventional deconvolution techniques are limited in their ability to recover features in imaging data by the Shannon–Nyquist sampling theorem. Here, we train a generative adversarial network (GAN) on a sample of 4550 images of nearby galaxies at 0.01 < z < 0.02 from the Sloan Digital Sky Survey and conduct 10× cross-validation to evaluate the results. We present a method using a GAN trained on galaxy images that can recover features from artificially degraded images with worse seeing and higher noise than the original with a performance that far exceeds simple deconvolution. The ability to better recover detailed features such as galaxy morphology from low signal to noise and low angular resolution imaging data significantly increases our ability to study existing data sets of astrophysical objects as well as future observations with observatories such as the Large Synoptic Sky Telescope (LSST) and the Hubble and James Webb space telescopes.

References:

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