Southeast Asia or Southeastern Asia is a subregion of Asia, consisting of the countries that are geographically south of China and Japan, east of India, west of Papua New Guinea, north of Australia. Southeast Asia is bordered to the north by East Asia, to the west by South Asia and the Bay of Bengal, to the east by Oceania and the Pacific Ocean, to the south by Australia and the Indian Ocean; the region is the only part of Asia that lies within the Southern Hemisphere, although the majority of it is in the Northern Hemisphere. In contemporary definition, Southeast Asia consists of two geographic regions: Mainland Southeast Asia known as Indochina, comprising parts of Northeast India, Laos, Thailand and West Malaysia. Maritime Southeast Asia known as Nusantara, the East Indies and Malay Archipelago, comprises the Andaman and Nicobar Islands of India, East Malaysia, the Philippines, East Timor, Christmas Island, the Cocos Islands. Taiwan is included in this grouping by many anthropologists; the region lies near the intersection of geological plates, with both heavy seismic and volcanic activities.
The Sunda Plate is the main plate of the region, featuring all Southeast Asian countries except Myanmar, northern Thailand, northern Laos, northern Vietnam, northern Luzon of the Philippines. The mountain ranges in Myanmar and peninsular Malaysia are part of the Alpide belt, while the islands of the Philippines are part of the Pacific Ring of Fire. Both seismic belts meet in Indonesia, causing the region to have high occurrences of earthquakes and volcanic eruptions. Southeast Asia covers about 4.5 million km2, 10.5% of Asia or 3% of earth's total land area. Its total population is about 8.5 % of the world's population. It is the third most populous geographical region in the world after East Asia; the region is culturally and ethnically diverse, with hundreds of languages spoken by different ethnic groups. Ten countries in the region are members of ASEAN, a regional organization established for economic, military and cultural integration amongst its members; the region, together with part of South Asia, was well known by Europeans as the East Indies or the Indies until the 20th century.
Chinese sources referred the region as 南洋, which means the "Southern Ocean." The mainland section of Southeast Asia was referred to as Indochina by European geographers due to its location between China and the Indian subcontinent and its having cultural influences from both neighboring regions. In the 20th century, the term became more restricted to territories of the former French Indochina; the maritime section of Southeast Asia is known as the Malay Archipelago, a term derived from the European concept of a Malay race. Another term for Maritime Southeast Asia is Insulindia, used to describe the region between Indochina and Australasia; the term "Southeast Asia" was first used in 1839 by American pastor Howard Malcolm in his book Travels in South-Eastern Asia. Malcolm only included the Mainland section and excluded the Maritime section in his definition of Southeast Asia; the term was used in the midst of World War II by the Allies, through the formation of South East Asia Command in 1943.
SEAC popularised the use of the term "Southeast Asia," although what constituted Southeast Asia was not fixed. However, by the late 1970s, a standard usage of the term "Southeast Asia" and the territories it encompasses had emerged. Although from a cultural or linguistic perspective the definitions of "Southeast Asia" may vary, the most common definitions nowadays include the area represented by the countries listed below. Ten of the eleven states of Southeast Asia are members of the Association of Southeast Asian Nations, while East Timor is an observer state. Papua New Guinea has stated that it might join ASEAN, is an observer. Sovereignty issues exist over some territories in the South China Sea; some southern parts of Mainland China, as well as Hong Kong and Taiwan, are considered as part of Southeast Asia by some authors. * Administrative centre in Putrajaya. Southeast Asia is geographically divided into two subregions, namely Mainland Southeast Asia and Maritime Southeast Asia. Mainland Southeast Asia includes: Maritime Southeast Asia includes: The Andaman and Nicobar Islands of India are geographically considered part of Maritime Southeast Asia.
Eastern Bangladesh and Northeast India have strong cultural ties with Southeast Asia and sometimes considered both South Asian and Southeast Asian. Sri Lanka has on some occasions been considered a part of Southeast Asia because of its cultural ties to mainland Southeast Asia; the rest of the island of New Guinea, not part of Indonesia, Papua New Guinea, is sometimes included, so are Palau and the Northern Mariana Islands, which were all part of the Spanish East Indies with strong cultural and linguistic ties to the region the Philippines. The eastern half of Indonesia and East Timor are considered to be biogeographically part of Oceania due to its distinctive faunal features. New Guinea and its surrounding islands are geologically considered as a part of Australian continent, connected via the Sahul Shelf; the region
Kannada is a Dravidian language spoken predominantly by Kannada people in India in the state of Karnataka, by significant linguistic minorities in the states of Andhra Pradesh, Tamil Nadu, Telangana and abroad. The language has 43.7 million native speakers, who are called Kannadigas. Kannada is spoken as a second and third language by over 12.9 million non-Kannada speakers living in Karnataka, which adds up to 56.6 million speakers. It is one of the scheduled languages of India and the official and administrative language of the state of Karnataka; the Kannada language is written using the Kannada script, which evolved from the 5th-century Kadamba script. Kannada is attested epigraphically for about one and a half millennia, literary Old Kannada flourished in the 6th-century Ganga dynasty and during the 9th-century Rashtrakuta Dynasty. Kannada has an unbroken literary history of over a thousand years. Kannada literature has been presented with 8 Jnanapith awards, the most for any Dravidian language and the second highest for any Indian language.
Based on the recommendations of the Committee of Linguistic Experts, appointed by the ministry of culture, the government of India designated Kannada a classical language of India. In July 2011, a center for the study of classical Kannada was established as part of the Central Institute of Indian Languages at Mysore to facilitate research related to the language. Kannada is a Southern Dravidian language, according to Dravidian scholar Sanford B. Steever, its history can be conventionally divided into three periods: Old Kannada from 450–1200 CE, Middle Kannada from 1200–1700, Modern Kannada from 1700 to the present. Kannada is influenced to an appreciable extent by Sanskrit. Influences of other languages such as Prakrit and Pali can be found in the Kannada language; the scholar Iravatham Mahadevan indicated that Kannada was a language of rich oral tradition earlier than the 3rd century BCE, based on the native Kannada words found in Prakrit inscriptions of that period, Kannada must have been spoken by a widespread and stable population.
The scholar K. V. Narayana claims that many tribal languages which are now designated as Kannada dialects could be nearer to the earlier form of the language, with lesser influence from other languages; the sources of influence on literary Kannada grammar appear to be three-fold: Pāṇini's grammar, non-Paninian schools of Sanskrit grammar Katantra and Sakatayana schools, Prakrit grammar. Literary Prakrit seems to have prevailed in Karnataka since ancient times; the vernacular Prakrit speaking people may have come into contact with Kannada speakers, thus influencing their language before Kannada was used for administrative or liturgical purposes. Kannada phonetics, vocabulary and syntax show significant influence from these languages; some naturalised words of Prakrit origin in Kannada are: baṇṇa derived from vaṇṇa, hunnime from puṇṇivā. Examples of naturalized Sanskrit words in Kannada are: varṇa, arasu from rajan, paurṇimā, rāya from rāja. Like the other Dravidian languages Kannada has borrowed words such as dina, surya, nimiṣa and anna.
Purava HaleGannada: This Kannada term translated means "Previous form of Old Kannada" was the language of Banavasi in the early Common Era, the Satavahana, Chutu Satakarni and Kadamba periods and thus has a history of over 2500 years. The Ashoka rock edict found at Brahmagiri has been suggested to contain words in identifiable Kannada. According to Jain tradition, the daughter of Rishabhadeva, the first Tirthankara of Jainism, invented 18 alphabets, including Kannada, which points to the antiquity of the language. Supporting this tradition, an inscription of about the 9th century CE, containing specimens of different alphabets Dravidian, was discovered in a Jain temple in the Deogarh fort. In some 3rd–1st century BCE Tamil inscriptions, words of Kannada influence such as'nalliyooraa','kavuDi' and posil' have been introduced; the use of the vowel a' as an adjective is not prevalent in Tamil but its usage is available in Kannada. Kannada words such as'gouDi-gavuDi' transform into Tamil's kavuDi' for lack of the usage of Ghosha svana in Tamil.
Hence the Kannada word'gavuDi' becomes'kavuDi' in Tamil.'Posil' was introduced into Tamil from Kannada and colloquial Tamil uses this word as'Vaayil'. In a 1st-century CE Tamil inscription, there is a personal reference to ayjayya', a word of Kannada origin. In a 3rd-century CE Tamil inscription there is usage of'oppanappa vIran'. Here the honorific'appa' to a person's name is an influence from Kannada. Another word of Kannada origin is found in a 4th-century CE Tamil inscription. S. Settar studied the'sittanvAsal' inscription of first century CE as the inscriptions at'tirupparamkunram','adakala' and'neDanUpatti'; the inscriptions were studied in detail by Iravatham Mahadevan also. Mahadevan argues that the words'erumi','kavuDi','poshil' and'tAyiyar' have their origin in Kannada because Tamil cognates are not available. Settar adds the words'nADu' and'iLayar' to this list. Mahadevan feels that some grammatical categories found in these inscriptions are unique to Kannada rather than Tamil. Both these scholars attribute these influences to the movements and spread of Jainas in these regions.
These inscriptions belong to the period between the first century BCE and fourth century CE. These are some examples that are proof of the early usage of a few Kannada origin words in early Tamil inscriptions before the common era and in the
Evolution of cetaceans
The evolutionary history of cetaceans is thought to have occurred in the Indian subcontinent from even-toed ungulates 50 million years ago, over a period of at least 15 million years. Cetaceans are aquatic marine mammals belonging to the order Artiodactyla, branched off from other artiodactyls around 50 mya. Cetaceans are thought to have evolved during the Eocene or earlier, sharing a closest common ancestor with hippopotamuses. Being mammals, they surface to breathe air. Discoveries starting in the late 1970s in Pakistan revealed several stages in the transition of cetaceans from land to sea; the two modern parvorders of cetaceans – Mysticeti and Odontoceti – are thought to have separated from each other around 28-33 million years ago in a second cetacean radiation, the first occurring with the archaeocetes. The adaptation of animal echolocation in toothed whales distinguishes them from aquatic archaeocetes and early baleen whales; the presence of baleen in baleen whales occurred with earlier varieties having little baleen, their size is linked to baleen dependence.
The aquatic lifestyle of cetaceans first began in the Indian subcontinent from even-toed ungulates 50 million years ago, over a period of at least 15 million years, however a jawbone discovered in Antarctica may reduce this to 5 million years. Archaeoceti is an extinct parvorder of Cetacea containing ancient whales; the traditional hypothesis of cetacean evolution, first proposed by Van Valen in 1966, was that whales were related to the mesonychids, an extinct order of carnivorous ungulates that resembled wolves with hooves and were a sister group of the artiodactyls. This hypothesis was proposed due to similarities between the unusual triangular teeth of the mesonychids and those of early whales. However, molecular phylogeny data indicates that whales are closely related to the artiodactyls, with hippopotamuses as their closest living relative; because of this and hippopotamuses are placed in the same suborder, Whippomorpha. Cetartiodactyla is a proposed name for an order containing both artiodactyls.
However, the earliest anthracotheres, the ancestors of hippos, do not appear in the fossil record until the Middle Eocene, millions of years after Pakicetus, the first known whale ancestor, appeared during the Early Eocene, implying the two groups diverged well before the Eocene. Since molecular analysis identifies artiodactyls as being closely related to cetaceans, mesonychids are an offshoot from Artiodactyla, cetaceans did not derive directly from them, but that the two groups may share a common ancestor; the molecular data are supported by the discovery of the earliest archaeocete. The skeletons of Pakicetus show. Instead, they are artiodactyls that began to take to the water soon after artiodactyls split from mesonychids. Archaeocetes retained aspects of their mesonychid ancestry which modern artiodactyls, modern whales, have lost; the earliest ancestors of all hoofed mammals were at least carnivorous or scavengers, today's artiodactyls and perissodactyls became herbivores in their evolution.
Whales, retained their carnivorous diet because prey was more available and they needed higher caloric content in order to live as marine endotherms. Mesonychids became specialized carnivores, but this was a disadvantage because large prey was uncommon; this may be why they were out-competed by better-adapted animals like the hyaenodontids and Carnivora. Indohyus was a small chevrotain-like animal that lived about 48 million years ago in what is now Kashmir, it belongs to the artiodactyl family Raoellidae, is believed to be the closest sister group of Cetacea. Indohyus is identified as an artiodactyl because it has two trochlea hinges, a trait unique to artiodactyls; the size of a raccoon or domestic cat, this omnivorous creature shared some traits of modern whales, most notably the involucrum, a bone growth pattern, the diagnostic characteristic of any cetacean. It showed signs of adaptations to aquatic life, including dense limb bones that reduce buoyancy so that they could stay underwater, which are similar to the adaptations found in modern aquatic mammals such as the hippopotamus.
This suggests a similar survival strategy to the African mousedeer or water chevrotain which, when threatened by a bird of prey, dives into water and hides beneath the surface for up to four minutes. The pakicetids were digitigrade hoofed mammals that are thought to be the earliest known cetaceans, with Indohyus being the closest sister group, they lived in the early Eocene, around 50 million years ago. Their fossils were first discovered in North Pakistan in 1979, located at a river not far from the shores of the former Tethys Sea. After the initial discovery, more fossils were found in the early Eocene fluvial deposits in northern Pakistan and northwestern India. Based on this discovery, pakicetids most lived in an arid environment with ephemeral streams and moderately developed floodplains millions of years ago. By using stable oxygen isotopes analysis, they were shown to drink fresh water, implying that they lived around freshwater bodies, their diet included land animals that approached water for drinking or some freshwater aquatic organi
Weaning is the process of introducing an infant human or mammal to what will be its adult diet while withdrawing the supply of its mother's milk. The process takes place only in mammals; the infant is considered to be weaned once it is no longer fed any breast milk. How and when to wean a human infant is controversial; the American Academy of Pediatrics recommends feeding a baby only breast milk for the first six months of its life. Many mothers find breastfeeding challenging in modern times when many mothers have to return to work soon after the birth of their child; the American Academy of Pediatrics, the World Health Organization, the National Health Service Choices UK, the National Health & Medical Research Council in Australia recommend waiting until 6 months to introduce baby food. However, many baby food companies market their "stage 1" foods to children between 4 and 6 months old with the precaution that the food is meant to be consumed in addition to breast milk or formula and is just for "practice".
These practice foods are soft and runny. Examples include mashed fruit and vegetables. Certain foods are recommended to be avoided; the United Kingdom's NHS recommends withholding foods including those "that contain wheat, nuts, peanut products, liver, fish, cows’ milk and soft or unpasteurised cheese" until a baby is six months old, as they may cause food allergies or make the baby ill. However, recommendations such as these have been called into question by research that suggests early exposure to potential allergens does not increase the likelihood of allergies, in some cases reduces it. In many cultures around the world, weaning progresses with the introduction of feeding the child food, prechewed by the parent along with continued breastfeed, a practice known as premastication; the practice was important throughout human history in that it gave a child a improved protein source in addition to preventing iron deficiency. The prechewing of food gives the baby long-term immunological benefits through factors in the mother's saliva.
However, premasticated food from caregivers of lower socioeconomic status in areas of endemic diseases can result in the passing of the disease to the child. No matter what age baby food is introduced, it is a messy affair, as young children do not have the coordination to eat "neatly". Coordination for using utensils properly and eating with dexterity takes years to develop. Many babies begin using utensils between 10 and 14 months, but most will not be able to feed themselves sufficiently well until about 2 or 3 years of age. At this point, the mother tries to force the infant to cease nursing, while the infant attempts to force the mother to continue. From an evolutionary perspective, weaning conflict may be considered the result of the cost of continued nursing to the mother in terms of reduced ability to raise future offspring, exceeding the benefits to the mother in terms of increased survival of the current infant; this can come about because future offspring will be related to the mother as the current infant, but will share less than 100% of the current infant's genes.
So, from the perspective of the mother's evolutionary fitness, it makes sense for her to cease nursing the current infant as soon as the cost to future offspring exceeds the benefit to the current infant. But, assuming the current infant shares 50% of the future offspring's genes, from the perspective of the infant's own evolutionary fitness, it makes sense for the infant to continue nursing until the cost to future offspring exceeds twice the benefit to itself. Weaning conflict has been studied for a variety including primates and canines. There are significant cultural variations in regards to weaning. Scientifically, one can ask various questions. At what age do various societies normatively choose to wean? In comparison with other animals similar primates, by various measures; as there are significant ranges and skew in these numbers, looking at the median is more useful than looking at the average. Considering biological measures of maturity, notably investigated by Katherine Ann Dettwyler, yields a range of ages from 2 1/2 years to 7 years as the weaning age analogous to other primates – the "natural age of weaning".
This depends on the measure, for example: weaning in non-human primates is associated with eruption of permanent molars. Other studies are possible, as in psychological factors. For example, Barbara Rogoff has noted, citing a 1953 study by Whiting & Child, that the most distressing time to wean a child is at 13–18 months. After this peak, weaning becomes progressively easier and less distressing for the child, with "older children wean themselves." In science, mice are used in laboratory experiments. When breeding laboratory mice in a controlled environment, the weaning is defined as the moment when the pups are transferred out of the mothers' cage. Weaning is recommended at 3 to 4 weeks after parturition. For pet carnivores such as do
The Ordovician is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.2 million years from the end of the Cambrian Period 485.4 million years ago to the start of the Silurian Period 443.8 Mya. The Ordovician, named after the Celtic tribe of the Ordovices, was defined by Charles Lapworth in 1879 to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same rock beds in northern Wales into the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed strata were different from those of either the Cambrian or the Silurian systems, placed them in a system of their own; the Ordovician received international approval in 1960, when it was adopted as an official period of the Paleozoic Era by the International Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian period, although the end of the period was marked by the Ordovician–Silurian extinction events.
Invertebrates, namely molluscs and arthropods, dominated the oceans. The Great Ordovician Biodiversification Event increased the diversity of life. Fish, the world's first true vertebrates, continued to evolve, those with jaws may have first appeared late in the period. Life had yet to diversify on land. About 100 times as many meteorites struck the Earth per year during the Ordovician compared with today; the Ordovician Period began with a major extinction called the Cambrian–Ordovician extinction event, about 485.4 Mya. It lasted for about 42 million years and ended with the Ordovician–Silurian extinction events, about 443.8 Mya which wiped out 60% of marine genera. The dates given are recent radiometric dates and vary from those found in other sources; this second period of the Paleozoic era created abundant fossils that became major petroleum and gas reservoirs. The boundary chosen for the beginning of both the Ordovician Period and the Tremadocian stage is significant, it correlates well with the occurrence of widespread graptolite and trilobite species.
The base of the Tremadocian allows scientists to relate these species not only to each other, but to species that occur with them in other areas. This makes it easier to place many more species in time relative to the beginning of the Ordovician Period. A number of regional terms have been used to subdivide the Ordovician Period. In 2008, the ICS erected a formal international system of subdivisions. There exist Baltoscandic, Siberian, North American, Chinese Mediterranean and North-Gondwanan regional stratigraphic schemes; the Ordovician Period in Britain was traditionally broken into Early and Late epochs. The corresponding rocks of the Ordovician System are referred to as coming from the Lower, Middle, or Upper part of the column; the faunal stages from youngest to oldest are: Late Ordovician Hirnantian/Gamach Rawtheyan/Richmond Cautleyan/Richmond Pusgillian/Maysville/Richmond Middle Ordovician Trenton Onnian/Maysville/Eden Actonian/Eden Marshbrookian/Sherman Longvillian/Sherman Soudleyan/Kirkfield Harnagian/Rockland Costonian/Black River Chazy Llandeilo Whiterock Llanvirn Early Ordovician Cassinian Arenig/Jefferson/Castleman Tremadoc/Deming/Gaconadian The Tremadoc corresponds to the Tremadocian.
The Floian corresponds to the lower Arenig. The Llanvirn occupies the rest of the Darriwilian, terminates with it at the base of the Late Ordovician; the Sandbian represents the first half of the Caradoc. During the Ordovician, the southern continents were collected into Gondwana. Gondwana started the period in equatorial latitudes and, as the period progressed, drifted toward the South Pole. Early in the Ordovician, the continents of Laurentia and Baltica were still independent continents, but Baltica began to move towards Laurentia in the period, causing the Iapetus Ocean between them to shrink; the small continent Avalonia separated from Gondwana and began to move north towards Baltica and Laurentia, opening the Rheic Ocean between Gondwana and Avalonia. The Taconic orogeny, a major mountain-building episode, was well under way in Cambrian times. In the early and middle Ordovician, temperatures were mild, but at the beginning of the Late Ordovician, from 460 to 450 Ma, volcanoes along the margin of the Iapetus Ocean spewed massive amounts of carbon dioxide, a greenhouse gas, into the atmosphere, turning the planet into a hothouse.
Sea levels were high, but as Gondwana moved south, ice accumulated into glaciers and sea levels dropped. At first, low-lying sea beds increased diversity, but glaciation led to mass extinctions as the seas drained and continental shelves became dry land. During the Ordovician, in fact during the Tremadocian, marine transgressions worldwide were the greatest for which evidence is preserved; these volcanic island arcs collided with proto North America to form the Appalachian mountains. By the end of the Late Ordovician the volcanic emissions had stopped. Gondwana had by that time neared the South Pole and was glaciated
The Miocene is the first geological epoch of the Neogene Period and extends from about 23.03 to 5.333 million years ago. The Miocene was named by Charles Lyell; the Miocene is followed by the Pliocene. As the earth went from the Oligocene through the Miocene and into the Pliocene, the climate cooled towards a series of ice ages; the Miocene boundaries are not marked by a single distinct global event but consist rather of regionally defined boundaries between the warmer Oligocene and the cooler Pliocene Epoch. The Apes first evolved and diversified during the early Miocene, becoming widespread in the Old World. By the end of this epoch and the start of the following one, the ancestors of humans had split away from the ancestors of the chimpanzees to follow their own evolutionary path during the final Messinian stage of the Miocene; as in the Oligocene before it, grasslands continued to forests to dwindle in extent. In the seas of the Miocene, kelp forests made their first appearance and soon became one of Earth's most productive ecosystems.
The plants and animals of the Miocene were recognizably modern. Mammals and birds were well-established. Whales and kelp spread; the Miocene is of particular interest to geologists and palaeoclimatologists as major phases of the geology of the Himalaya occurred during the Miocene, affecting monsoonal patterns in Asia, which were interlinked with glacial periods in the northern hemisphere. The Miocene faunal stages from youngest to oldest are named according to the International Commission on Stratigraphy: Regionally, other systems are used, based on characteristic land mammals. Of the modern geologic features, only the land bridge between South America and North America was absent, although South America was approaching the western subduction zone in the Pacific Ocean, causing both the rise of the Andes and a southward extension of the Meso-American peninsula. Mountain building took place in western North America and East Asia. Both continental and marine Miocene deposits are common worldwide with marine outcrops common near modern shorelines.
Well studied continental exposures occur in Argentina. India continued creating dramatic new mountain ranges; the Tethys Seaway continued to shrink and disappeared as Africa collided with Eurasia in the Turkish–Arabian region between 19 and 12 Ma. The subsequent uplift of mountains in the western Mediterranean region and a global fall in sea levels combined to cause a temporary drying up of the Mediterranean Sea near the end of the Miocene; the global trend was towards increasing aridity caused by global cooling reducing the ability of the atmosphere to absorb moisture. Uplift of East Africa in the late Miocene was responsible for the shrinking of tropical rain forests in that region, Australia got drier as it entered a zone of low rainfall in the Late Miocene. During the Oligocene and Early Miocene the coast of northern Brazil, south-central Peru, central Chile and large swathes of inland Patagonia were subject to a marine transgression; the transgressions in the west coast of South America is thought to be caused by a regional phenomenon while the rising central segment of the Andes represents an exception.
While there are numerous registers of Oligo-Miocene transgressions around the world it is doubtful that these correlate. It is thought that the Oligo-Miocene transgression in Patagonia could have temporarily linked the Pacific and Atlantic Oceans, as inferred from the findings of marine invertebrate fossils of both Atlantic and Pacific affinity in La Cascada Formation. Connection would have occurred through narrow epicontinental seaways that formed channels in a dissected topography; the Antarctic Plate started to subduct beneath South America 14 million years ago in the Miocene, forming the Chile Triple Junction. At first the Antarctic Plate subducted only in the southernmost tip of Patagonia, meaning that the Chile Triple Junction lay near the Strait of Magellan; as the southern part of Nazca Plate and the Chile Rise became consumed by subduction the more northerly regions of the Antarctic Plate begun to subduct beneath Patagonia so that the Chile Triple Junction advanced to the north over time.
The asthenospheric window associated to the triple junction disturbed previous patterns of mantle convection beneath Patagonia inducing an uplift of ca. 1 km that reversed the Oligocene–Miocene transgression. Climates remained moderately warm, although the slow global cooling that led to the Pleistocene glaciations continued. Although a long-term cooling trend was well underway, there is evidence of a warm period during the Miocene when the global climate rivalled that of the Oligocene; the Miocene warming b
In ethology, territory is the sociographical area that an animal of a particular species defends against conspecifics. Animals that defend territories in this way are referred to as territorial. Territoriality is only shown by a minority of species. More an individual or a group of animals has an area that it habitually uses but does not defend; the home ranges of different groups of animals overlap, or in the overlap areas, the groups tend to avoid each other rather than seeking to expel each other. Within the home range there may be a core area that no other individual group uses, again, this is as a result of avoidance; the ultimate function of animals inhabiting and defending a territory is to increase the individual fitness or inclusive fitness of the animals expressing the behaviour. Fitness in this biological sense relates to the ability of an animal to raise young; the proximate functions of territory defense vary. For some animals, the reason for such protective behaviour is to acquire and protect food sources, nesting sites, mating areas, or to attract a mate.
Among birds, territories have been classified as six types. Type A: An'all-purpose territory' in which all activities occur, e.g. courtship, mating and foraging Type B: A mating and nesting territory, not including most of the area used for foraging. Type C: A nesting territory which includes the nest plus a small area around it. Common in colonial waterbirds. Type D: A pairing and mating territory; the type of territory defended by males in lekking species. Type E: Roosting territory. Type F: Winter territory which includes foraging areas and roost sites. May be equivalent to the Type A territory, or for a migratory species, may be on the wintering grounds. Reports of territory size can be confused by a lack of distinction between home range and the defended territory; the size and shape of a territory can vary according to its purpose, the amount and quality of resources it contains, or the geography. The size is a compromise of resource needs, defense costs, predation pressure and reproductive needs.
Some species of squirrels may claim as much as 10 hectares of territory. For European badgers, a home range may be as small as 30 hectares in a good rural habitat, but as large as 300 hectares in a poor habitat. On average, a territory may be 50 hectares, with main setts at least 500 metres apart. In urban areas, territories can be as small as 5 hectares, if they can obtain enough food from bird tables, food waste or artificial feeding in suburban gardens. Spotted hyenas have variable territory sizes, ranging from less than 4,000 hectares in the Ngorongoro Crater to over 100,000 hectares in the Kalahari. In birds, golden eagles have territories of 9,000 hectares, least flycatchers' territories are about 600 square metres and gulls have territories of only a few square centimetres in the immediate vicinity of the nest. Territories can be linear. Sanderlings forage on sandflats; when on beaches, they feed either in flocks or individual territories of 10 to 120 metres of shoreline. The time to develop territories varies between animals.
The marine iguana is a lekking reptile. Males start to establish small display territories two months ahead of the mating season. Rather than retaining a territory by fighting, for some animals this can be a 3-stage process. Many animals create "sign-posts" to advertise their territory. Sometimes these sign-posts are on the boundary thereby demarcating the territory, or, may be scattered throughout the territory; these communicate to other animals that the territory is occupied and may communicate additional information such as the sex, reproductive status or dominance status of the territory-holder. Sign-posts may communicate information by olfactory, auditory, or visual means, or a combination of these. If an intruder progresses further into the territory beyond the sign-posts and encounters the territory-holder, both animals may begin ritualized aggression toward each other; this is a series of stylised postures, displays, etc. which function to solve the territory dispute without actual fighting as this could injure either or both animals.
Ritualized aggression ends by one of the animals fleeing. If this does not happen, the territory may be defended by actual fighting, although this is a last resort. Scent marking known as territorial marking or spraying when this involves urination, is a behaviour used by animals to identify their territory. Most this is accomplished by depositing strong-smelling substances contained in the urine, faeces, or, from specialised scent glands located on various areas of the body; the scent contains pheromones or carrier proteins such as the major urinary proteins to stabilize the odours and maintain them for longer. The animal sniffing the scent displays a flehmen response to assist in detecting the mark. Scent marking is performed by scent rubbing in many mammals. In many mammal species, scent marking is more frequent during the breeding season. Felids such as leopards and jaguars mark by rubbing themselves against vegetation. Fraser, Andrew Ferguson. Feline Behaviour and Welfare. CABI. p. 53. ISBN 9781845939267.
Prosimians and New World monkeys use scent marking, including urine washing, to communicate. Many ungulates, for example the blue wildebeest, use scent marking from two glands, the preorbital gland and a scent gland in the hoof. Territorial scent marking