a b Munn, C.; Fernandez, M. (1997). "Infant development". In Sodaro, Carol (ed.). Orangutan Species Survival Plan Husbandry Manual. Chicago Zoological Park. pp.59–66. OCLC 40349739.

a b van Schaik, Carel P.; Knott, Cheryl D. (2001). "Geographic variation in tool use onNeesia fruits in orangutans". American Journal of Physical Anthropology. 114 (4): 331–342. doi: 10.1002/ajpa.1045. PMID 11275962. Lesson, René-Primevère (1827). Manuel de mammalogie ou Histoire naturelle des mammifères (in French). Roret, Libraire. p. 32. On December 21st, 2019, Redditor /u/HansMcBean posted an image macro to /r/ memes [5] using the image, garnering over 33,500 upvotes in roughly a year (shown below). The next day the meme was reposted to /r/MemeEconomy, [6] garnering over 400 upvotes in the same rough span of time. 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". Primates. 50 (1): 56–64. doi: 10.1007/s10329-008-0117-y. PMID 19052691. S2CID 708682.After reaching adolescence at four or five years, these animals become increasingly independent of their mothers. Sexual maturity for males and females in zoos is around six years, although it can take up to 10 years or more for a wild female to mature and longer than that for males. Females may stay with their mothers until they are well into their teens, allowing them to observe mothering skills as they watch their younger siblings being raised. Physical maturity, especially in males, may not be reached for several years after sexual maturity. McDowell, Robin (18 January 2009). "Palm oil frenzy threatens to wipe out orangutans". Associated Press. Archived from the original on 20 January 2009 . Retrieved 18 January 2009. Orangutans can brachiate —swing hand over hand —but they normally move cautiously through large trees by climbing and walking. This allows them to distribute their weight among the branches. Orangutans' hands make them graceful and swift while swinging, but it makes walking on the ground very slow and awkward. Harper, Douglas. "Orangutan". Online Etymology Dictionary. Archived from the original on 4 November 2012 . Retrieved 4 May 2012.

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, Tintinnabulum naturae (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 The Orang Outang is narrated by a pure orangutan in captivity in the US, writing a letter critiquing Boston society to her friend in Java. [6] :108–09 Lameira, A. R.; etal. (2021). "Orangutan information broadcast via consonant-like and vowel-like calls breaches mathematical models of linguistic evolution". Biology Letters. 17 (9). doi: 10.1098/rsbl.2021.0302. PMC 8478518. PMID 34582737. a b c Singh, Ranjeet (26 January 2011). "Orang-utans join the genome gang". Nature. doi: 10.1038/news.2011.50. Archived from the original on 27 January 2011 . Retrieved 27 January 2011. Other major conservation centres in Indonesia include those at Tanjung Puting National Park, Sebangau National Park, Gunung Palung National Park and Bukit Baka Bukit Raya National Park in Borneo and the Gunung Leuser National Park and Bukit Lawang in Sumatra. In Malaysia, conservation areas include Semenggoh Wildlife Centre and Matang Wildlife Centre also in Sarawak, and the Sepilok Orang Utan Sanctuary in Sabah. [136] Major conservation centres headquartered outside the orangutans' home countries include Frankfurt Zoological Society, [137] Orangutan Foundation International, which was founded by Galdikas, [138] and the Australian Orangutan Project. [139] Conservation organisations such as the Orangutan Land Trust work with the palm oil industry to improve sustainability and encourages the industry to establish conservation areas for orangutans. [140] [141] See also Hilloowala, R. A.; Trent, R. B. (1988). "Supraorbital ridge and masticatory apparatus I: Primates". Human Evolution. 3 (5): 343–50. doi: 10.1007/BF02447216. S2CID 83923845.a b c d Galdikas, Birute M. F. (1988). "Orangutan Diet, Range, and Activity at Tanjung Puting, Central Borneo". International Journal of Primatology. 9 (1): 1–35. doi: 10.1007/BF02740195. S2CID 40513842.

Meijaard, E.; Buchori, B.; Hadiprakarsa, Y.; Utami-Atmoko, S. S.; etal. (2011). "Quantifying Killing of Orangutans and Human-Orangutan Conflict in Kalimantan, Indonesia". PLOS ONE. 6 (11): e27491. Bibcode: 2011PLoSO...627491M. doi: 10.1371/journal.pone.0027491. PMC 3214049. PMID 22096582. Knox, A; Markx, J; How, E; Azis, A; Hobaiter, C; an Veen, F. J. F; Morrogh-Bernard, H (2019). "Gesture use in communication between mothers and offspring in wild Orang-Utans ( Pongo pygmaeus wurmbii) from the Sabangau Peat-Swamp Forest, Borneo". International Journal of Primatology. 40 (3): 393–416. doi: 10.1007/s10764-019-00095-w. S2CID 195329265.Deaner, R. O.; van Schaik, C. P.; Johnson, V. (2006). "Do some taxa have better domain-general cognition than others? A meta-analysis of nonhuman primate studies". Evolutionary Psychology. 4: 149–96. doi: 10.1177/147470490600400114. S2CID 16702785. Archived from the original on 19 August 2021 . Retrieved 19 June 2020. a b Singleton, I.; van Schaik, C. P. (2002). "The Social Organisation of a population of Sumatran orang-utans". Folia Primatologica. 73 (1): 1–20. doi: 10.1159/000060415. PMID 12065937. S2CID 13557435. Orangutans usually have a single baby, and twins are rare. Gestation is seven-and-a-half to eight-and-a-half months. From birth, orangutan infants cling to their mothers as they maneuver through the trees. The orangutan has the longest period of dependence on the mother of any other land-dwelling animal, including humans. Infant orangutans can nurse until they are six to seven years old. However, weaning is highly variable, depending on the mother. It is thought that weaning occurs sooner if food is abundant and the infant can switch to solids.

a b Didik, Prasetyo; Ancrenaz, Marc; Morrogh-Bernard, Helen C.; Atmoko, S. Suci Utami; Wich, Serge A.; van Schaik, Carel P. (2009). "Nest building in orangutans". In Wich, Serge A.; Atmoko, S. Suci Utami; Setia, Tatang Mitra; van Schaik, Carel P. (eds.). Orangutans: Geographic Variation in Behavioral Ecology and Conservation. Oxford University Press. pp.270–75. ISBN 978-0-19-921327-6. Archived from the original on 24 April 2016 . Retrieved 16 December 2015. Orangutan shaved, made up and prostituted to men for six years". The Week. 28 November 2018. Archived from the original on 3 October 2020 . Retrieved 29 April 2020. One of the most intriguing and intelligent animals to ever exist, the orangutan derives its name from the Malay word for "man of the forest." Orangutans live ninety percent of their lives in the treetops of the majestic forests of Southeast Asia's Sumatra and Borneo. Typically found 1,500 meters above sea level, these special animals are known for much more than just representing King Louis in the Jungle Book. Habitat And Origin A female orangutan and her offspring swinging in the tree. The word was first attested in English in 1693 by physician John Bulwer in the form Orang-Outang, [1] [7] and variants ending with -ng 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 incorrect. [8] [9] [10] The loss of "h" in utan and the shift from -ng to -n has been taken to suggest the term entered English through Portuguese. [4] In Malay, the term was first attested in 1840, not as an indigenous name but referring to how the English called the animal. [11] The word 'orangutan' in Malay and Indonesian today was borrowed from English or Dutch in the 20th century—explaining why the initial 'h' of 'hutan' is also missing. [4] Batang is an adult female Bornean orangutan. She has pale skin on her face, especially around her eyes and mouth, and is smaller in stature than the Zoo’s other female orangutans. Batang tends to be very social; she enjoys spending a few days with some of the orangutans, then switches groups, spending a few days with the other orangutans. Batang was born in December 1996 at the Lincoln Park Zoo and came to the Smithsonian’s National Zoo in 2004 as part of the Bornean Orangutan Species Survival Plan (SSP).Iris is an adult female hybrid orangutan. She’s charismatic and can be quite silly and playful, but also quite stubborn at times. She is the star of several cognitive research programs and enjoys participating in daily research demonstrations at Think Tank. She was born at the Zoo on April 15, 1987, and was named after the IRS (Internal Revenue Service) because of her birth date. van Schaik, CP; Van Noordwijk, MA; Wich, SA. (2006). "Innovation in wild Bornean orangutans ( Pongo pygmaeus wurmbii)". Behaviour. 143 (7): 839–76. doi: 10.1163/156853906778017944. Rijksen, H. D. (December 1978). "A field study on Sumatran orang utans ( Pongo pygmaeus abelii, Lesson 1827): Ecology, Behaviour and Conservation". The Quarterly Review of Biology. 53 (4): 493–94. doi: 10.1086/410942. JSTOR 2826733. Lameira, A. R.; Shumaker, R. W. (2019). "Orangutans show active voicing through a membranophone". Scientific Reports. 9 (1): 12289. Bibcode: 2019NatSR...912289L. doi: 10.1038/s41598-019-48760-7. PMC 6707206. PMID 31444387.