Orangutan - Knowledge

2573: 2210: 116: 858: 1650:; they live a more solitary lifestyle than the other great apes. Bornean orangutans are generally more solitary than Sumatran orangutans. Most social bonds occur between adult females and their dependent and weaned offspring. Resident females live with their offspring in defined home ranges that overlap with those of other adult females, which may be their immediate relatives. One to several resident female home ranges are encompassed within the home range of a resident male, who is their main mating partner. Interactions between adult females range from friendly to avoidance to antagonistic. Flanged males are hostile to both other flanged males and unflanged males, while unflanged males are more peaceful towards each other. 1856: 1876:

infant has with its mother declines. When an orangutan reaches the age of one-and-a-half years, its climbing skills improve and it will travel through the canopy holding hands with other orangutans, a behaviour known as "buddy travel". After two years of age, juvenile orangutans will begin to move away from their mothers temporarily. They reach adolescence at six or seven years of age and are able to live alone but retain some connections with their mothers. Females may nurse their offspring for up to eight years, which is more than any other mammal. Typically, orangutans live over 30 years both in the wild and in captivity.

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according to the task at hand, and preference was given to oral tool use. This preference was also found in an experimental study of captive orangutans. Orangutans have been observed to use sticks to poke at catfish, causing them to leap out of the water so the orangutan can grab them. Orangutan have also been documented to keep tools for later. When building a nest, orangutans appear to be able to determine which branches would better support their body weight.

9207: 8764: 13054: 10536: 2667: 11492: 1432: 1978:-like vocalisations in response to physical contact such as wrestling, play chasing or tickling. This suggests that laughter derived from a common origin among primate species and therefore evolved before the origin of humans. Orangutans can learn to mimic new sounds by purposely controlling the vibrations of their vocal folds, a trait that led to speech in humans. 1658:

his home range. Both resident and transient orangutans aggregate on large fruiting trees to feed. The fruits tend to be abundant, so competition is low and individuals may engage in social interactions. Orangutans will also form travelling groups with members moving between different food sources. They are often consortships between an adult male and a female.

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with a series of low frequency noises known collectively as the "rolling call". When uncomfortable, an orangutan will produce a "kiss squeak", which involves sucking in air through pursed lips. Mothers produce throatscrapes to keep in contact with their offspring. Infants make soft hoots when distressed. When building a nest, orangutans will produce smacks or

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relatively tolerant of each other; this creates favourable conditions for the spreading of new behaviours. Further evidence that highly social orangutans are more likely to exhibit cultural behaviours came from a study of leaf-carrying behaviours of formerly captive orangutans that were being rehabilitated on the island of Kaja in Borneo.

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In May 2017, the BOS rescued an albino orangutan from captivity in a remote village in Kapuas Hulu, on the island of Kalimantan in Indonesian Borneo. According to volunteers at BOS, albino orangutans are extremely rare (one in ten thousand). This is the first albino orangutan the organisation has seen in 25 years of activity.

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differences were cultural: first, the extent of the differences increased with distance, suggesting cultural diffusion was occurring, and second, the size of the orangutans' cultural repertoire increased according to the amount of social contact present within the group. Social contact facilitates cultural transmission.

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orangutan then does the same to smaller, leafier branches to create a "mattress". After this, the ape stands and braids the tips of branches into the mattress. Doing this increases the stability of the nest. Orangutans make their nests more comfortable by creating "pillows", "blankets", "roofs" and "bunk-beds".

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for a strong grip on branches as they travel high in the trees. The resting configuration of the fingers is curved, creating a suspensory hook grip. With the thumb out of the way, the fingers (and hands) can grip securely around objects with a small diameter by resting the tops of the fingers against

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in ex-captive populations. Orangutans in Suaq Balimbing were recorded to develop a tool kit for use in foraging which consisted of both insect-extraction sticks for use in the hollows of trees and seed-extraction sticks for harvesting seeds from hard-husked fruit. The orangutans adjusted their tools

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adult males develop distinctive cheek pads or flanges and make long calls that attract females and intimidate rivals; younger subordinate males do not and more resemble adult females. Orangutans are the most solitary of the great apes: social bonds occur primarily between mothers and their dependent

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Anthropometamorphosis: man transform'd: or, The artificiall changling, historically presented, in the mad and cruel gallantry, foolish bravery, ridiculous beauty, filthy finenesse, and loathsome loveliness of most nations, fashioning and altering their bodies from the mould intended by nature; with

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A female orangutan was rescued from a village brothel in Kareng Pangi village, Central Kalimantan, in 2003. The orangutan was shaved and chained for sexual purposes. Since being freed, the orangutan, named Pony, has been living with the BOS. She has been re-socialised to live with other orangutans.

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the listener into believing they are larger animals. In 2003, researchers from six different orangutan field sites who used the same behavioural coding scheme compared the behaviours of the animals from each site. They found each orangutan population used different tools. The evidence suggested the

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Females do most of the caring of the young. The mother will carry the infant while travelling, suckle it and sleep with it. During its first four months, the infant is almost never without physical contact and clings to its mother's belly. In the following months, the amount of physical contact the

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and establish their home ranges by age 11. Females tend to live near their birth range, while males disperse farther but may still visit their birth range within their larger home range. They enter a transient phase, which lasts until a male can challenge and displace a dominant, resident male from

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that the Sumatran and Bornean species diverged 4.9 to 2.9 mya. By contrast, the 2011 genome study suggested that these two species diverged as recently as circa 400,000 years ago. The study also found that orangutans evolved at a slower pace than both chimpanzees and humans. A 2017 genome

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Mother orangutans and offspring also use several different gestures and expressions such as beckoning, stomping, lower lip pushing, object shaking and "presenting" a body part. These communicate goals such as "acquire object", "climb on me", "climb on you", "climb over", "move away", "play change:

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Compared to their relatives in Borneo, Sumatran orangutans are more slender with paler and longer hair and a longer face. Tapanuli orangutans resemble Sumatran orangutans more than Bornean orangutans in body build and hair colour. They have shaggier hair, smaller skulls, and flatter faces than the

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Orangutans communicate with various vocals and sounds. Males will make long calls, both to attract females and to advertise themselves to other males. These calls have three components; they begin with grumbles, peak with pulses and end with bubbles. Both sexes will try to intimidate conspecifics

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and construct elaborate sleeping nests each night from branches and foliage. The apes' learning abilities have been studied extensively. There may be distinctive cultures within populations. Orangutans have been featured in literature and art since at least the 18th century, particularly in works

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to signal fertility. A female first gives birth around 15 years of age and they have a six to nine year interbirth interval, the longest among the great apes. Gestation is around nine months long and infants are born at a weight of 1.5–2 kg (3.3–4.4 lb). Usually only a single infant is

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in other parts of Borneo and in Sumatra. While some communities hunted them for food and decoration, others placed taboos on such practices. In central Borneo, some traditional folk beliefs consider it bad luck to look an orangutan in the face. Some folk tales involve orangutans mating with and

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trade and bones are secretly sold in souvenir shops in several cities in Indonesian Borneo. Conflicts between locals and orangutans also pose a threat. Orangutans that have lost their homes often raid agricultural areas and end up being killed by villagers. Locals may also be motivated to kill

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fruit. The orangutans of Suaq Balimbing were found to be avid users of insect and seed-extraction tools when compared to other wild orangutans. The scientists suggested these differences are cultural as they do not correlate with habitat. The orangutans at Suaq Balimbing are closely spaced and

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Construction of a night nest is done by following a sequence of steps. Initially, a suitable tree is located. Orangutans are choosy about sites, though nests can be found in many tree species. To establish a foundation, the ape grabs the large branches under it and bends them so they join. The

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variety of Malay, but the age of the Old Javanese sources mentioned above make Old Malay a more likely origin for the term. Cribb and colleagues (2014) suggest that Bontius' account referred not to apes (as this description was from Java where the apes were not known to be from) but to humans

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Locke, D. P.; Hillier, L. W.; Warren, W. C.; Worley, K. C.; Nazareth, L. V.; Muzny, D. M.; Yang, S. P.; Wang, Z.; Chinwalla, A. T.; Minx, P.; Mitreva, M.; Cook, L.; Delehaunty, K. D.; Fronick, C.; Schmidt, H.; Fulton, L. A.; Fulton, R. S.; Nelson, J. O.; Magrini, V.; Pohl, C.; Graves, T. A.;

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Estimates in the 2000s found that around 6,500 Sumatran orangutans and around 54,000 Bornean orangutans remain in the wild. A 2016 study estimates a population of 14,613 Sumatran orangutans in the wild, twice that of previous population estimates, while 2016 estimates suggest 104,700 Bornean

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specialised for either day or night use. These are carefully constructed; young orangutans learn from observing their mother's nest-building behaviour. In fact, nest-building allows young orangutans to become less dependent on their mother. From six months of age onwards, orangutans practise

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Orangutans also include leaves in their diet, which take up 25% of their average foraging time. Leaves are eaten more when fruit is less available, but even during times of fruit abundance, orangutans will eat leaves 11–20% of the time. They appear to depend on the leaf and stem material of

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Most of the day is spent feeding, resting, and travelling. They start the day feeding for two to three hours in the morning. They rest during midday, then travel in the late afternoon. When evening arrives, they prepare their nests for the night. Potential predators of orangutans include

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van Noordwijk, Maria A.; Sauren, Simone E.B.; Nuzuar; Abulani, Ahbam; Morrogh-Bernard, Helen C.; Atmoko, S. Suci Utami; van Schaik, Carel P. (2009). "Development of Independence". In Wich, Serge A.; Atmoko, S. Suci Utami; Setia, Tatang Mitra; van Schaik, Carel P. (eds.).

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orangutans for food or because of their perceived danger. Mother orangutans are killed so their infants can be sold as pets. Between 2012 and 2017, the Indonesian authorities, with the aid of the Orangutan Information Center, seized 114 orangutans, 39 of which were pets.

1353:; females typically stand 115 cm (45 in) tall and weigh around 37 kg (82 lb), while adult males stand 137 cm (54 in) tall and weigh 75 kg (165 lb). Compared to humans, they have proportionally long arms, a male orangutan having an 940:

study found that the Bornean and Tapanuli orangutans diverged from Sumatran orangutans about 3.4 mya, and from each other around 2.4 mya. Millions of years ago, orangutans travelled from mainland Asia to Sumatra and then Borneo as the islands were connected by

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of the great apes, orangutans spend most of their time in trees. They have proportionally long arms and short legs, and have reddish-brown hair covering their bodies. Adult males weigh about 75 kg (165 lb), while females reach about 37 kg (82 lb).

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Little was known about orangutan behaviour until the field studies of Birutė Galdikas, who became a leading authority on the apes. When she arrived in Borneo in 1971, Galdikas settled into a primitive bark-and-thatch hut at a site she dubbed Camp Leakey, in

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orangutans exist in the wild. A 2018 study found that Bornean orangutans declined by 148,500 individuals from 1999 to 2015. Fewer than 800 Tapanuli orangutans are estimated to still exist, which puts the species among the most endangered of the great apes.

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Wich, Serge A.; de Vries, Hans; Ancrenaz, Marc; Perkins, Lori; Shumaker, Robert W.; Suzuki, Akira; van Schaik, Carel P. (2009). "Orangutan life history variation". In Wich, Serge A.; Atmoko, S. Suci Utami; Setia, Tatang Mitra; van Schaik, Carel P. (eds.).

1872:. This may be because they cannot ensure they will sire a female's next offspring, because she does not immediately begin ovulating again after her infant dies. There is evidence that females with offspring under six years old generally avoid adult males. 1928: 1926: 1924: 1959:. Without any training, the orangutans succeeded in pulling off an object to get food in the first session. Over the course of 30 sessions, the apes succeeded more quickly, having learned to coordinate. An adult orangutan has been documented to pass the 2458:

Galdikas reported that her cook was sexually assaulted by a captive male orangutan. The ape may have suffered from a skewed species identity and forced copulation is a standard mating strategy for low-ranking male orangutans. American animal trafficker

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groups have urged a stop to such acts, considering them abusive. Starting in the 1960s, zoos became more concerned with education and orangutans' exhibits were designed to mimic their natural environment and let them display their natural behaviours.

1436: 2147:, who observed the animals and dissected some specimens, gave the first scientific description of the orangutan. Camper mistakenly thought that flanged and unflanged male orangutans were different species, a misconception corrected after his death. 1927: 4877:

Atmoko, S. Suci Utami; Singleton, Ian; van Noordwijk, Maria A.; van Schaik, Carel P.; Setia, Tatang Mitra (2009). "Male–male relationships in orangutans". In Wich, Serge A.; Atmoko, S. Suci Utami; Setia, Tatang Mitra; van Schaik, Carel P. (eds.).

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figures of those transformations. To which artificial and affected deformations are added, all the native and national monstrosities that have appeared to disfigure the humane fabrick. With a vindication of the regular beauty and honesty of nature

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Zimmermann, N; Pirovino, M; Zingg, R; Clauss, M; Kaup, F. J.; Heistermann, M; Hatt, J. M.; Steinmetz, H. W. (2011). "Upper respiratory tract disease in captive orangutans (Pongo sp.): prevalence in 20 European zoos and predisposing factors".

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the inside of the palm, thus creating a double-locked grip. Their feet have four long toes and an opposable big toe, giving them hand-like dexterity. The hip joints also allow for their legs to rotate similarly to their arms and shoulders.

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by not developing the distinctive cheek pads, pronounced throat pouches, long fur, or long calls until a resident dominant male is absent. The transformation from unflanged to flanged can occur quickly. Flanged males attract females in

5754: 2256:(1895), the protagonist Reuben Power travels to Borneo and captures an orangutan to train it to speak so he can "know what a beast like that might think of us". Orangutans are featured prominently in the 1963 science fiction novel 2329:

features an intelligent orangutan which serves a university professor but has sinister motives; he plots against humanity and stalks a female student assistant. Other stories have portrayed orangutans helping humans, such as

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Wich, Serge A.; Singleton, Ian; Nowak, Matthew G.; Utami Atmoko, Sri Suci; Nisam, Gonda; Arif, Sugesti Mhd.; Putra, Rudi H.; Ardi, Rio; Fredriksson, Gabriella; Usher, Graham; Gaveau, David L. A.; Kühl, Hjalmar S. (2016).

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Foitová, Ivona; Huffman, Michael A.; Wisnu, Nurcahyo; Olšanský, Milan (2009). "Parasites and their impacts on orangutan health". In Wich, Serge A.; Atmoko, S. Suci Utami; Setia, Tatang Mitra; van Schaik, Carel P. (eds.).

1974:: mother orangutans remain silent in the presence of a perceived threat but when it passes, the mother produces an alarm call to their offspring to teach them about the danger. Orangutans and other great apes show 3961:

Wang, Cui-Bin; Zhao, Ling-Xia; Jin, Chang-Zhu; Wang, Yuan; Qin, Da-Gong; Pan, Wen-Shi (December 2014). "New discovery of Early Pleistocene orangutan fossils from Sanhe Cave in Chongzuo, Guangxi, southern China".

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Cheyne, S. M.; Thompson, C. J.; Phillips, A. C.; Hill, R. M.; Limin, S. H. (2007). "Density and population estimate of gibbons (Hylobates albibarbis) in the Sabangau catchment, Central Kalimantan, Indonesia".

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Ibrahim, Yasamin Kh.; Tshen, Lim Tze; Westaway, Kira E.; Cranbrook, Earl of; Humphrey, Louise; Muhammad, Ros Fatihah; Zhao, Jian-xin; Peng, Lee Chai (December 2013). "First discovery of Pleistocene orangutan

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van Schaik, C. P.; Ancrenaz, M.; Borgen, G.; Galdikas, B.; Knott, C. D.; Singleton, I.; Suzuki, A.; Utami, S. S.; Merrill, M.; et al. (2003). "Orangutan cultures and the evolution of material culture".

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Wild orangutans in Tuanan, Borneo, were reported to use tools in acoustic communication. They use leaves to amplify the kiss squeak sounds they produce. The apes may employ this method of amplification to

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between 24.1 and 19.7 million years ago (mya), and the orangutans diverged from the African great ape lineage between 19.3 and 15.7 mya. Israfil and colleagues (2011) estimated based on

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and biological anthropologist Cheryl D. Knott further investigated tool use in different wild orangutan populations. They compared geographic variations in tool use related to the processing of

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Schwartz, J. H.; Vu The Long; Nguyen Lan Cuong; Le Trung Kha; Tattersall, I. (1995). "A review of the Pleistocene hominoid fauna of the Socialist Republic of Vietnam (excluding Hylobatidae)".

2248:. The novel satirises the class and political system of Britain. Oran's purity and status as a "natural man" stands in contrast to the immorality and corruption of the "civilised" humans. In 1329:

date to between 66 and 57,000 years ago. The range of orangutans had contracted significantly by the end of the Pleistocene, most likely because of the reduction of forest habitat during the

2228:(The Bell of Nature, 1772) is told from the point of view of a human-orangutan hybrid who calls himself the "metaphysician of the woods". Around 50 years later, the anonymously written work 6433:

Russon, A. E.; Compost, A.; Kuncoro, P.; Ferisa, A. (2014). "Orangutan Fish Eating, Primate Aquatic Fauna Eating, and Their Implications for the Origins of Ancestral Hominin Fish Eating".

897:), despite populations being six to seven times higher in Borneo. The researchers hope these data may help conservationists preserve the endangered ape, as well as learn more about human 7602: 1844:

on her, the occurrence of which is unusually high among mammals. Females prefer to mate with the fitter flanged males, forming pairs with them and benefiting from their protection. Non-

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when sea levels were much lower. The present range of Tapanuli orangutans is thought to be close to where ancestral orangutans first entered what is now Indonesia from mainland Asia.

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Studies in the wild indicate that flanged male orangutans plan their movements in advance and signal them to other individuals. Experiments have also suggested that orangutans can

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Nater, Alexander; Mattle-Greminger, Maja P.; Nurcahyo, Anton; Nowak, Matthew G.; Manuel, Marc de; Desai, Tariq; Groves, Colin; Pybus, Marc; Sonay, Tugce Bilgin (2 November 2017).

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Scott, A. M.; Knott, C. D.; Susanto, T. W. (2019). "Are Male Orangutans a Threat to Infants? Evidence of Mother–Offspring Counterstrategies to Infanticide in Bornean Orangutans (

2103:. Animal rights groups like Great Ape Project Argentina argued the ruling should apply to all species in captivity, and legal specialists from the Argentina's Federal Chamber of 7730: 3745: 1923: 273: 250: 1260:, which lived 5–7 mya in Thailand, is believed to be the closest known relative of the living orangutans and inhabited similar environments. The largest known primate, 2143:

Europeans became aware of the existence of the orangutan in the 17th century. Explorers in Borneo hunted them extensively during the 19th century. In 1779, Dutch anatomist

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Teboekhorst, I.; Schürmann, C.; Sugardjito, J. (1990). "Residential status and seasonal movements of wild orang-utans in the Gunung Leuser Reserve (Sumatera, Indonesia)".

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Wich, S. A.; Swartz, K. B.; Hardus, M. E.; Lameira, A. R.; Stromberg, E.; Shumaker, R. W. (2008). "A case of spontaneous acquisition of a human sound by an orangutan".

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who had been observing Rakus at a nature preserve, "Five days later the facial wound was closed, while within a few weeks it had healed, leaving only a small scar".

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Xu, X.; Arnason, U. (1996). "The mitochondrial DNA molecule of sumatran orangutan and a molecular proposal for two (Bornean and Sumatran) species of orangutan".

1415:. Compared to other great apes, they infrequently descend to the ground where they are more cumbersome. Unlike gorillas and chimpanzees, orangutans are not true 1253:, which lived in India and Pakistan from 12.5 mya until 8.5 mya. These animals likely lived in drier and cooler environments than orangutans do today. 6975: 6308:

Fox, E. A.; Sitompul, A. F.; van Schaik, C. P. (1999). "Intelligent tool use in wild Sumatran orangutans". In Parker, S; Mitchell, R. W.; Miles, H. L. (eds.).

8273: 8184: 582:, meaning "forest". The locals originally used the term for actual forest-dwelling humans, but the word underwent a semantic extension to include apes of the 7016: 11838: 11780: 11718: 4944: 8458: 7064: 5311:"Female reproductive strategies in orangutans, evidence for female choice and counterstrategies to infanticide in a species with frequent sexual coercion" 1305:

have been found in Vietnam, and multiple fossil subspecies have been described from several parts of southeastern Asia. It is unclear if these belong to

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Orangutans first appeared in Western fiction in the 18th century and have been used to comment on human society. Written by the pseudonymous A. Ardra,

1952:", which involves an individual aiding another with the expectation of being paid back. Orangutans are the first nonhuman species documented to do so. 5137: 2796: 12558: 12252: 11745: 11711: 11647: 11136: 10874: 10751: 10699: 6333:

van Schaik, C. P.; Fox, E. A.; Sitompul, A. F. (1996). "Manufacture and use of tools in wild Sumatran orangutans – implications or human evolution".

2391:. He rejected the company of other animals, aside from a dog, and preferred to be with humans. He was occasionally taken on coach rides clothed in a 2083:, orangutans, and gorillas not to be used for animal experiments. In December 2014, a court in Argentina ruled that an orangutan named Sandra at the 746: 5064:

Mitani, J. C.; Grether, G. F.; Rodman, P. S.; Priatna, D. (1991). "Associations among wild orang-utans: sociality, passive aggregations or chance".

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are found in many languages. This spelling (and pronunciation) has remained in use in English up to the present but has come to be regarded as

2163:. Galdikas became an outspoken advocate for orangutans and the preservation of their rainforest habitat, which is rapidly being devastated by 13248: 12039: 11654: 10846: 10360: 10200: 10179: 10059: 10052: 10016: 10009: 10002: 9981: 9967: 6690:

Russon, AE; Handayani, DP; Kuncoro, P; Ferisa, A. (2007). "Orangutan leaf-carrying for nest-building: toward unraveling cultural processes".

1552:, which can take up 57–80% of their foraging time. Even during times of scarcity, fruit is 16% of their feeding time. Fruits with soft pulp, 4065:

Liao, Wei; Harrison, Terry; Yao, Yanyan; Liang, Hua; Tian, Chun; Feng, Yuexing; Li, Sheng; Bae, Christopher J.; Wang, Wei (September 2022).

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of an orangutan is underdeveloped. Females and juveniles have relatively circular skulls and thin faces while mature males have a prominent

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of about 2 m (6 ft 7 in), and short legs. They are covered in long reddish hair that starts out bright orange and darkens to

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In June 2008, Spain would become the first country to recognise the rights of some non-human great apes, based on the guidelines of the

10326: 10291: 10235: 10143: 10122: 10080: 9940: 7169: 7734: 3749: 2447:, an orangutan of the San Diego Zoo, became world famous in the 1980s for multiple escapes from his enclosures. He was nicknamed "the 10685: 10599: 10367: 10333: 10298: 10270: 10242: 9136: 9033: 6624: 2990: 13196: 10744: 10312: 10263: 9146: 3463:

Bradon-Jones, D.; Eudey, A. A.; Geissmann, T.; Groves, C. P.; Melnick, D. J.; Morales, J. C.; Shekelle, M.; Stewart, C. B. (2004).

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By the early 19th century, orangutans were being kept in captivity. In 1817, an orangutan joined several other animals in London's

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Rubis, June Mary (2020). "The orang utan is not an indigenous name: knowing and naming the maias as a decolonizing epistemology".

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in Sumatra. In Malaysia, conservation areas include Semenggoh Wildlife Centre and Matang Wildlife Centre also in Sarawak, and the

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Didik, Prasetyo; Ancrenaz, Marc; Morrogh-Bernard, Helen C.; Atmoko, S. Suci Utami; Wich, Serge A.; van Schaik, Carel P. (2009).

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Wich, S A; Meijaard, E; Marshall, A J; Husson, S; et al. (2002). "Distribution and conservation status of the orang-utan (

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Several organisations are working for the rescue, rehabilitation and reintroduction of orangutans. The largest of these is the

8367: 5161:"Orangutan information broadcast via consonant-like and vowel-like calls breaches mathematical models of linguistic evolution" 3216: 13240: 9151: 8339: 7388: 7163: 6317: 5633: 4887: 4439: 4352: 4176: 3692: 3389: 2948: 2869: 2245: 1388:. The cheek pads are made mostly of fatty tissue and are supported by the musculature of the face. The throat pouches act as 13227: 7203:

Studies in History and Philosophy of Science Part C: Studies in History and Philosophy of Biological and Biomedical Sciences

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Galdikas, B. M. F. (1982). "Orang-Utan tool use at Tanjung Putting Reserve, Central Indonesian Borneo (Kalimantan Tengah)".

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Galdikas, B. M. F. (1984). "Adult female sociality among wild orangutans at Tanjung Puting Reserve". In Small, M. F. (ed.).

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refers only to the apes and not forest-dwelling humans. The word is not originally Javanese, but was borrowed from an early

9831: 7040:

Race and Aesthetics in the Anthropology of Petrus Camper (1722–1789) (Studies in the History of Ideas in the Low Countries)

4982:

van Schaik, C. P.; Preuschoft, S.; Watts, D. P. (2004). "Great ape social systems". In Russon, A. E.; Begun, D. R. (eds.).

3727: 3472: 2467:

to orphaned orangutan babies in hopes of keeping them alive long enough to sell to a trader, which would be an instance of

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of mammals. They are legally protected from capture, harm or killing in both Malaysia and Indonesia, and are listed under

2232:

is narrated by a pure orangutan in captivity in the US, writing a letter critiquing Boston society to her friend in Java.

2087:

must be moved to a sanctuary in Brazil to provide her "partial or controlled freedom". Sandra has since been relocated to

1986:, was recorded spontaneously whistling after hearing a caretaker. She appears to whistle without expecting a food reward. 1365:

with age, while the skin is grey-black. Though largely hairless, males' faces can develop some hair, giving them a beard.

8251: 8160: 5269: 4957: 2616: 5901:

Chalmeau, Raphaël; Lardeux, Karine; Brandibas, Pierre; Gallo, Alain (1997). "Cooperative problem solving by orangutans (

3537:

Markovic, C.; Cree, A.; Dinh, H. H.; Hume, J.; Kovar, C. L.; Fowler, G. R.; Lunter, G.; Meader, S.; et al. (2011).

2536:

when she began studying them in 1971. By the 2000s, orangutan habitats decreased rapidly because of logging, mining and

522:. Human activities have caused severe declines in populations and ranges. Threats to wild orangutan populations include 9073: 8312: 7126: 7105: 7047: 5421: 5003: 4917: 4861: 4592: 4558: 3664: 3155: 2636: 6967: 7452: 7425: 4201: 3789: 1944:

has a touch-screen computer on which their two Sumatran orangutans play games. A 2008 study of two orangutans at the

1786:. Orangutan calls display consonant- and vowel-like components and they maintain their meaning over great distances. 7632: 6560:

van Casteren, A.; Sellers, W. I.; Thorpe, S. K. S.; Coward, S.; Crompton, R. H.; Myatt, J. P.; Ennos, A. R. (2012).

3779: 13337: 8277: 8192: 3186: 2522: 719: 7304: 4608:

Morrogh-Bernard HC, Foitová I, Yeen Z, Wilkin P, de Martin R, Rárová L, Doležal K, Nurcahyo W, Olšanský M (2017).

115: 13347: 13253: 9083: 7012: 6622:

van Schaik, Carel P.; Knott, Cheryl D. (2001). "Geographic variation in tool use onNeesia fruits in orangutans".

4725: 4254: 1610:, which involves consuming soil and other earth substances. They will uproot soil from the ground as well as eat 820:

was confirmed as a full species based on molecular evidence published in 1996, and three distinct populations on

13322: 8800: 8453: 3296: 2940: 2468: 1849: 710:, which describes two anthropoid "monsters" named Pongo and Engeco. He is now believed to have been describing 8421: 1544:

Although orangutans may consume leaves, shoots, and bird eggs, fruit is the most important part of their diet.

885:

to have its genome sequenced. Subsequently, the Bornean species had its genome sequenced. Bornean orangutans (

570:

The name "orangutan" (also written orang-utan, orang utan, orangutang, and ourang-outang) is derived from the

438:, orangutans were originally considered to be one species. From 1996, they were divided into two species: the 13292: 9412: 2858:

Malay Words and Malay Things: Lexical Souvenirs from an Exotic Archipelago in German Publications Before 1700

2460: 2297: 2214: 2204: 1841: 5725:"Do some taxa have better domain-general cognition than others? A meta-analysis of nonhuman primate studies" 4803:

Singleton, I.; van Schaik, C. P. (2002). "The Social Organisation of a population of Sumatran orang-utans".

2604: 2209: 491:

offspring. Fruit is the most important component of an orangutan's diet, but they will also eat vegetation,

9452: 5129: 2766: 2640: 2632: 2628: 1956: 13332: 13235: 13144: 11244: 9783: 8488: 5940:

Suárez, S. D.; Gallup, G. G. (1981). "Self-recognition in chimpanzees and orangutans, but not gorillas".

5820: 4938:

Delgado, R. A. Jr.; van Schaik, C. P. (2000). "The behavioral ecology and conservation of the orangutan (

2620: 2612: 2306: 7586: 4514:

Galdikas, Birute M. F. (1988). "Orangutan Diet, Range, and Activity at Tanjung Puting, Central Borneo".

2592:

and which operates projects such as the Nyaru Menteng Rehabilitation Program founded by conservationist

1564:

and berries. Orangutans are thought to be the sole fruit disperser for some plant species including the

13149: 9778: 9280: 9270: 9236: 9156: 9008: 6841:"Active self-treatment of a facial wound with a biologically active plant by a male Sumatran orangutan" 4991: 4765: 4030: 3139: 2485: 2258: 1971: 1868:

born; twins are a rare occurrence. Unlike many other primates, male orangutans do not seem to practise

462:), was identified definitively in 2017. The orangutans are the only surviving species of the subfamily 20: 6469: 2127:

Orangutans were known to the native people of Sumatra and Borneo for millennia. The apes are known as

515:

and they have been kept in captive facilities around the world since at least the early 19th century.

9275: 9120: 9088: 9038: 8993: 7756: 4549:

Rodman, P. S. (1988). "Diversity and consistency in ecology and behavior". In Schwartz, J. H. (ed.).

2680: 2585: 2415: 2331: 1945: 1893: 857: 12331: 4217:

Hilloowala, R. A.; Trent, R. B. (1988). "Supraorbital ridge and masticatory apparatus I: Primates".

3464: 2548:

plantations in response to international demand. Hunting is also a major problem, as is the illegal

2244:

features Sir Oran Haut Ton, an orangutan who lives among English people and becomes a candidate for

507: 9824: 7544: 7413: 7151:

Centralizing Fieldwork: Critical Perspectives from Primatology, Biological, and Social Anthropology

3926: 2861: 2707: 2403:

who was dressed in human clothing and learned to drink tea. She is remembered for her meeting with

2249: 1848:

females do not usually resist copulation with unflanged males, as the chance of conception is low.

806:

by Lacépède in 1799. The populations on the two islands were suggested to be separate species when

9018: 8473: 2631:

in Sabah. Major conservation centres headquartered outside the orangutans' home countries include

2593: 1325:

that date to 60,000 years ago. The youngest remains from South China, which are teeth assigned to

141: 13053: 12089: 11907: 11314: 9265: 9114: 9093: 5619: 5133: 5107: 4066: 3280: 2685: 2302: 1949: 1468: 672: 635:

In Western sources, the first printed attestation of the word for the apes is in Dutch physician

624:

at least a thousand years ago. Hence the ultimate origin of the term "orangutan" as denoting the

559: 7562:

Nowak, Matthew G.; Rianti, Puji; Wich, Serge A.; Meijaard, Erik; Fredriksson, Gabriella (2017).

4168: 4162: 3602: 1937: 1291:

is found as part of the faunal complex in the Pleistocene cave assemblage in Vietnam, alongside

13279: 13074: 11368: 11072: 10453: 9753: 9003: 8481: 4995: 4876: 4584: 4573: 3412:

Nater, A.; Mattle-Greminger, M. P.; Nurcahyo, A.; Nowak, M. G.; et al. (2 November 2017).

3381: 2608: 2423: 2070: 1266:, was also a member of Ponginae and lived in China, from 2 mya to 300,000 years ago. 8329: 7699: 7380: 6737:"Tool use in wild orang-utans modifies sound production: a functionally deceptive innovation?" 5624:. In Wich, Serge A.; Atmoko, S. Suci Utami; Setia, Tatang Mitra; van Schaik, Carel P. (eds.). 5621: 5309:

Knott, Cheryl Denise; Thompson, Melissa Emery; Stumpf, Rebecca M; McIntyre, Matthew H (2009).

5208:

Knox, A; Markx, J; How, E; Azis, A; Hobaiter, C; an Veen, F. J. F; Morrogh-Bernard, H (2019).

499:, insects and bird eggs. They can live over 30 years, both in the wild and in captivity. 13274: 12154: 9605: 9372: 9229: 6659:

van Schaik, CP; Van Noordwijk, MA; Wich, SA. (2006). "Innovation in wild Bornean orangutans (

6562:"Nest-building orangutans demonstrate engineering know-how to produce safe, comfortable beds" 3920:

Harrison, Terry; Jin, Changzhu; Zhang, Yingqi; Wang, Yuan; Zhu, Min (December 2014). "Fossil

3813:

Bhandari, A.; Kay, R. F.; Williams, B. A.; Tiwari, B. N.; Bajpai, S.; Heironymus, T. (2018).

3516: 2537: 2287: 2088: 1869: 1532:

as an anti-inflammatory balm. Captive animals may suffer an upper respiratory tract disease.

1488: 945: 555: 519: 13266: 7841:

Davis, J. T.; Mengersen, K.; Abram, N. K.; Ancrenaz, M.; Wells, J. A.; Meijaard, E. (2013).

7417: 7149: 3815:"First record of the Miocene hominoid Sivapithecus from Kutch, Gujarat state, western India" 3653:

Our vanishing relative: the status of wild orang-utans at the close of the twentieth century

1837:

with their characteristic long calls, which may also suppress development in younger males.

1815: 13170: 13121: 11388: 9492: 9352: 9063: 8998: 8958: 7982: 7854: 7795: 6794: 6573: 6514: 6344: 6192: 6084: 6025: 5677: 5571: 4629: 4471: 3971: 3935: 3826: 3552: 3305: 2644: 2576:

Zoologische Gesellschaft Frankfurt Programm Director Peter Pratje works with orangutans in

2418:

and to perform tricks. Notable orangutan "character actors" include: Jacob and Rosa of the

2062: 2028: 1936:

Orangutans are among the most intelligent non-human primates. Experiments suggest they can

1654: 1614:

from tree trunks. Orangutans also visit the sides of cliffs or earth depressions for their

1540: 1372:

volume is 397 cm. The cranium is elevated relative to the face, which is incurved and

1330: 10535: 7781: 7563: 7482: 5263:

Fox, E. A. (2002). "Female tactics to reduce sexual harassment in the Sumatran orangutan (

2140:

kidnapping humans. There are even stories of hunters being captured by female orangutans.

8: 13317: 12831: 12212: 11491: 11409: 11354: 9817: 9680: 9660: 9575: 9560: 9517: 9507: 9502: 9472: 9407: 9337: 9053: 9043: 8304: 7784:"Quantifying Killing of Orangutans and Human-Orangutan Conflict in Kalimantan, Indonesia" 6335: 4805: 4431: 4421: 4417: 4340: 4252:

Winkler, L. A. (1989). "Morphology and relationships of the orangutan fatty cheek pads".

4028:

sp.) fossils in Peninsular Malaysia: Biogeographic and paleoenvironmental implications".

3656: 3485: 2982: 2235: 2041: 1975: 1783: 1647: 1456: 1452: 1412: 1322: 774: 680: 535: 511:

that comment on human society. Field studies of the apes were pioneered by primatologist

487: 482: 7986: 7858: 7799: 7524:

Ancrenaz, M.; Gumal, M.; Marshall, A. J.; Meijaard, E.; Wich, S. A.; Husson, S. (2016).

6873: 6840: 6798: 6577: 6559: 6518: 6348: 6196: 6088: 6029: 5681: 5575: 5558:

Smith, Tanya M.; Austin, Christine; Hinde, Katie; Vogel, Erin R.; Arora, Manish (2017).

5019:

van Schaik, C. P. (1999). "The socioecology of fission-fusion sociality in orangutans".

4633: 4475: 3975: 3939: 3924:

from the Early Pleistocene Gigantopithecus fauna of Chongzuo, Guangxi, southern China".

3830: 3556: 3309: 3274: 1855: 679:

and the shift from -ng to -n has been taken to suggest the term entered English through

12474: 11664: 11604: 11284: 11200: 10446: 9793: 9738: 9535: 9497: 9387: 9362: 9332: 8973: 8931: 8911: 8793: 8606: 8588: 8057: 8003: 7964: 7877: 7842: 7818: 7783: 7680: 7069: 6818: 6761: 6736: 6717: 6596: 6561: 6537: 6502: 6415: 6368: 6263: 6215: 6180: 6161: 6107: 6072: 6048: 6011: 5992: 5922: 5878: 5851: 5746: 5700: 5665: 5594: 5559: 5540: 5486: 5461: 5389: 5337: 5310: 5286: 5245: 5185: 5160: 5081: 5046: 5021: 4961: 4830: 4782: 4742: 4701: 4652: 4609: 4531: 4394: 4369: 4279: 4234: 4136: 4094: 3849: 3814: 3714: 3573: 3538: 3489: 3329: 3106: 3068: 3031: 2788: 2427: 2419: 2267: 2240: 2188: 2104: 1979: 1916: 1840:

Unflanged males wander widely in search of oestrous females and upon finding one, will

1283: 1017: 1003: 870: 866: 838: 808: 455: 447: 349: 322: 308: 302: 136: 8983: 8134: 7782:

Meijaard, E.; Buchori, B.; Hadiprakarsa, Y.; Utami-Atmoko, S. S.; et al. (2011).

7653: 6294: 5953: 5664:

Lameira, A. R.; Hardus, M. E.; Shumaker, R. W.; Wich, S. A.; Menken, S. B. J. (2015).

5077: 4778: 3996: 3161: 2120: 2007: 1803: 512: 13261: 13157: 12053: 12029: 11702: 11014: 9798: 9788: 9773: 9763: 9758: 9748: 9723: 9675: 9640: 9512: 9487: 9457: 9437: 9422: 9397: 9367: 9342: 9078: 8921: 8817: 8597: 8394: 8335: 8308: 8116: 8108: 8049: 8028:"Global demand for natural resources eliminated more than 100,000 Bornean Orangutans" 8008: 7882: 7823: 7672: 7525: 7458: 7448: 7421: 7384: 7369: 7286: 7278: 7228: 7220: 7159: 7101: 7043: 6905: 6878: 6860: 6810: 6766: 6709: 6641: 6601: 6542: 6450: 6407: 6360: 6313: 6255: 6220: 6153: 6112: 6053: 6012:"Wild Orangutan Males Plan and Communicate Their Travel Direction One Day in Advance" 5984: 5883: 5852:"Calculated reciprocity after all: computation behind token transfers in orang-utans" 5801: 5724: 5705: 5663: 5629: 5599: 5544: 5491: 5438: 5417: 5410: 5381: 5342: 5249: 5190: 5111: 5038: 4999: 4984: 4913: 4906: 4883: 4857: 4853: 4822: 4693: 4689: 4657: 4588: 4577: 4554: 4489: 4435: 4399: 4385: 4348: 4271: 4197: 4172: 4123: 4098: 4086: 4047: 3899: 3854: 3795: 3785: 3719: 3660: 3578: 3445: 3385: 3321: 3151: 3110: 3035: 2944: 2865: 2819: 2792: 2652: 2431: 2400: 2395:

and hat and even given drinks at an inn where he behaved politely for the hosts. The

2374: 2354: 2345: 2076: 2066: 1910: 1570: 1472: 1362: 1350: 1274: 973: 925: 906: 890: 862: 794: 621: 439: 296: 267: 123: 7406: 6822: 6419: 6372: 6165: 5996: 5926: 5750: 5393: 5290: 5085: 5050: 4965: 4902: 4834: 4786: 4535: 4283: 4238: 3493: 3012:

Tan, Peter (October 1998). "Malay loan words across different dialects of English".

2965: 13162: 12961: 12605: 12498: 12181: 11964: 11900: 11870: 11807: 10894: 10810: 10655: 9670: 9620: 9555: 9382: 9377: 9177: 8947: 8371: 8098: 8088: 8061: 8039: 7998: 7990: 7973: 7944: 7872: 7862: 7813: 7803: 7684: 7664: 7581: 7539: 7376: 7336:"The missing lynx and five other animal escapees including Ken Allen the Orangutan" 7210: 6997: 6868: 6852: 6802: 6756: 6748: 6721: 6701: 6692: 6672: 6633: 6591: 6581: 6532: 6522: 6442: 6399: 6352: 6290: 6247: 6210: 6200: 6143: 6102: 6092: 6043: 6033: 5976: 5949: 5914: 5873: 5865: 5793: 5736: 5695: 5685: 5589: 5579: 5530: 5522: 5481: 5473: 5373: 5332: 5322: 5278: 5235: 5225: 5180: 5172: 5073: 5030: 4953: 4814: 4774: 4734: 4685: 4647: 4637: 4523: 4479: 4389: 4381: 4319: 4263: 4226: 4128: 4078: 4039: 4002: 3979: 3943: 3889: 3844: 3834: 3709: 3701: 3610: 3568: 3560: 3543: 3481: 3435: 3425: 3333: 3313: 3208: 3143: 3098: 3060: 3023: 2778: 2701: 2507: 2164: 2084: 2046: 2015: 1591:

during times of low fruit abundance. Other food items consumed by the apes include

1528: 1510: 1476: 1464: 1460: 1389: 936: 898: 846:, came with a surprising twist: it is more closely related to the Bornean species, 603: 6267: 5776:

de Blois, S. T.; Novak, M. A.; Bond, M. (1998). "Object Permanence in Orangutans (

4705: 3102: 2410:

Zoos and circuses in the Western world would continue to use orangutans and other

1852:

has been recorded in the context of both affiliative and aggressive interactions.

1341: 877:

The Sumatran orangutan genome was sequenced in January 2011. Following humans and

13112: 12884: 12853: 12845: 12729: 12629: 12484: 12454: 12071: 11917: 11854: 11684: 11634: 11620: 11613: 11567: 11361: 11156: 10826: 10779: 10713: 10028: 9733: 9695: 9690: 9685: 9655: 9630: 9625: 9600: 9580: 9570: 9392: 9327: 9167: 8892: 8882: 8658: 8649: 7867: 7840: 7808: 6474: 6446: 6038: 5856: 5690: 5210:"Gesture use in communication between mothers and offspring in wild Orang-Utans ( 4082: 4043: 3983: 3947: 3839: 3147: 3051: 2672: 2577: 2451:" and was the subject of a fan club, T-shirts, bumper stickers and a song titled 2388: 2335: 2311: 2292: 1994: 1864: 1659: 1419:, instead bending their digits and walking on the sides of their hands and feet. 1416: 1404: 1262: 913: 779: 644: 636: 7523: 7215: 7198: 5797: 3705: 1321:

and mainland Southeast Asia and South China. Teeth of orangutans are known from

13010: 12971: 12902: 12759: 12749: 12719: 12696: 12686: 12676: 12588: 12537: 12522: 12507: 12444: 12423: 12413: 12080: 12060: 11675: 11402: 11379: 10837: 9700: 9665: 9645: 9615: 9590: 9565: 9550: 9447: 9347: 9304: 7155: 6856: 6676: 6527: 6205: 5967:

Robert, S. (1986). "Ontogeny of mirror behavior in two species of great apes".

5741: 5526: 5230: 5209: 4642: 4427: 2648: 2503: 2404: 2152: 2036: 1964: 1863:

Unlike females of other non-human great ape species, orangutans do not exhibit

1611: 1484: 1381: 1301: 1255: 1233: 739: 727: 688: 571: 422: 315: 13126: 9442: 8370:. Australian Department of the Environment and Water Resources. Archived from 8167: 8093: 8076: 8044: 8027: 7668: 7199:"Going the whole orang: Darwin, Wallace and the natural history of orangutans" 6705: 6251: 6148: 6131: 5918: 5477: 5282: 5102:

Munn, C.; Fernandez, M. (1997). "Infant development". In Sodaro, Carol (ed.).

4484: 4459: 4324: 4307: 3683:

Israfil, H.; Zehr, S. M.; Mootnick, A. R.; Ruvolo, M.; Steiper, M. E. (2011).

3430: 3413: 3270: 3027: 2783: 1967:. Mirror tests with a 2-year-old orangutan failed to reveal self-recognition. 813: 13311: 12989: 12824: 12815: 12544: 12514: 12464: 12434: 12276: 12242: 12174: 12096: 12046: 12005: 11984: 11583: 11543: 11264: 11227: 11183: 11176: 11126: 11102: 10722: 10645: 10412: 9635: 9462: 9210: 8786: 8767: 8112: 7572: 7530: 7491: 7224: 7194: 6909: 6898:"Orangutan seen treating wound with medicinal herb in first for wild animals" 6864: 6432: 6386:

O'Malley, R. C.; McGrew, W. C. (2000). "Oral tool use by captive orangutans (

5406: 4303: 3775: 3014: 2533: 2491: 2448: 2439: 2435: 2263: 2218: 2144: 2092: 1999: 1627: 1592: 1501: 784: 703: 653: 598: 539: 492: 280: 66: 8077:"Morphometric, Behavioral, and Genomic Evidence for a New Orangutan Species" 7462: 6839:

Laumer, Isabelle B.; Rahman, Arif; Rahmaeti, Tri; et al. (2 May 2024).

6806: 6586: 5115: 4161:

van Schaik, C.; MacKinnon, J. (2001). "Orangutans". In MacDonald, D. (ed.).

3799: 3784:(3rd ed.). Baltimore: Johns Hopkins University Press. pp. 183–84. 3414:"Morphometric, Behavioral, and Genomic Evidence for a New Orangutan Species" 1884: 13097: 13021: 12950: 12861: 12838: 12786: 12769: 12739: 12581: 12529: 12383: 12164: 12117: 12022: 11957: 11947: 11937: 11847: 11729: 11691: 11576: 11423: 11416: 11324: 11062: 11048: 10981: 10860: 10630: 10588: 10386: 9925: 9467: 9028: 9013: 8988: 8120: 8053: 8012: 7994: 7886: 7827: 7676: 7340: 7232: 6882: 6814: 6770: 6752: 6713: 6645: 6605: 6546: 6454: 6411: 6259: 6224: 6157: 6116: 6097: 6057: 5988: 5980: 5887: 5869: 5709: 5603: 5584: 5495: 5385: 5360:

Fox, Elizabeth A (2001). "Homosexual behavior in wild Sumatran orangutans (

5346: 5327: 5194: 5176: 5042: 4981: 4826: 4697: 4661: 4493: 4403: 4275: 4267: 4090: 4051: 3903: 3858: 3771: 3723: 3582: 3449: 3124: 2695: 2624: 2589: 2282: 2192: 2180: 1615: 1385: 1333:. Though they may have survived into the Holocene in Cambodia and Vietnam. 1249: 1243: 933: 929: 714:, but in the 18th century, the terms orangutan and pongo were used for all 259: 7290: 6364: 5805: 3325: 2366: 2039:

in 2022, a male Sumatran orangutan, known to researchers as Rakus, chewed

1202: 13209: 13136: 13106: 12927: 12110: 11991: 11974: 11738: 11344: 11254: 11119: 11082: 11002: 10941: 10662: 10115: 9427: 9402: 9221: 9023: 8978: 8847: 8682: 7628: 7447:. Steven Lehrer. Lubbock, Tex.: Texas Tech University Press. p. 37. 7442: 6009: 3614: 2511: 2392: 2325: 2184: 2050: 1960: 1941: 1897:

nest-building and gain proficiency by the time they are three years old.

1526:

are reported in young individuals. Orangutans also use the plant species

1373: 1369: 1219:

The three orangutan species are the only extant members of the subfamily

1121: 941: 660: 471: 426: 418: 333: 41: 8368:"Tax Deductible Organisations (Register of Environmental Organisations)" 7700:"Endangered Orangutans: Fires, Poaching and Palm Oil: Facts and Details" 7603:"Endangered Orangutans Gain From Eco-Friendly Shifts in Palm Oil Market" 5849: 4986:

The Evolution of Thought: Evolutionary Origins of Great Ape Intelligence

4719:

Rijksen, H. D. (December 1978). "A field study on Sumatran orang utans (

4367: 3564: 3239: 3178: 2733: 2495: 1638: 13201: 12403: 12195: 11522: 11509: 11459: 11395: 11334: 11237: 11220: 11112: 11055: 11028: 10991: 10961: 10951: 10676: 10402: 10284: 9988: 9933: 9885: 9840: 9417: 9319: 9309: 9172: 8863: 8703: 8544: 8103: 7965:"Land-cover changes predict steep declines for the Sumatran orangutan ( 7312: 6356: 5626: