On the edge of extinction". Sumatran Orangutan Society. Archived from the original on 8 May 2020 . Retrieved 1 July 2020.

Hardus, M. E.; Lameira, A. R.; van Schaik, C. P.; Wich, S. A. (2009). "Tool use in wild orang-utans modifies sound production: a functionally deceptive innovation?". Proceedings of the Royal Society B. 276 (1673): 3689–94. doi: 10.1098/rspb.2009.1027. PMC 2817314. PMID 19656794. You can typically tell male and female orangutans apart by looking at them. Males and females have flabby throat sacs, which become very large in adult males. Adult males have deep chests and much longer body hair than females do. Males also typically develop large cheek pads, which demonstrate genetic fitness and amplify their long calls. Bower, B. (18 April 2011). "Orangutans use simple tools to catch fish". Wired. Archived from the original on 8 July 2013 . Retrieved 5 August 2013. Butler, R. A. (20 August 2009). "Rehabilitation not enough to solve orangutan crisis in Indonesia". Mongabay. Archived from the original on 5 January 2012 . Retrieved 26 March 2012.Wich, S A; Meijaard, E; Marshall, A J; Husson, S; etal. (2002). "Distribution and conservation status of the orang-utan ( Pongo spp.) on Borneo and Sumatra: how many remain?". Oryx. 42 (3): 329–39. doi: 10.5167/uzh-3914. 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". Journal of Human Evolution. 77: 50–63. doi: 10.1016/j.jhevol.2014.06.007. PMID 25038033. 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.

pongo, n.1". OED Online. Oxford University Press. Archived from the original on 19 August 2021 . Retrieved 4 October 2018. The presence of a fully mature dominant male may suppress secondary sexual characteristics (long hair, face pads, beards and enlarged throat sacs) in other less dominant males, and, in some cases, a wild male orangutan may never develop cheek pads. This suppression of secondary sexual characteristic does not, however, suppress his fertility, and it has been shown that unflanged male orangutans are as successful in siring offspring as fully flanged males. 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. Rodman, P. S. (1988). "Diversity and consistency in ecology and behavior". In Schwartz, J. H. (ed.). Orang-utan biology. Oxford University Press. pp.31–51. ISBN 978-0195043716.The oldest known record of Pongo is from the Early Pleistocene of Chongzuo, consisting of teeth ascribed to extinct species P. weidenreichi. [29] [30] Pongo is found as part of the faunal complex in the Pleistocene cave assemblage in Vietnam, alongside Giganopithecus, though it is known only from teeth. Some fossils described under the name P.hooijeri 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 P.pygmaeus or P.abelii or, in fact, represent distinct species. [31] During the Pleistocene, Pongo had a far more extensive range than at present, extending throughout Sundaland and mainland Southeast Asia and South China. Teeth of orangutans are known from Peninsular Malaysia that date to 60,000 years ago. [32] The youngest remains from South China, which are teeth assigned to P. weidenreichi, date to between 66 and 57,000 years ago. [33] The range of orangutans had contracted significantly by the end of the Pleistocene, most likely because of the reduction of forest habitat during the Last Glacial Maximum.Though they may have survived into the Holocene in Cambodia and Vietnam. [29] [32] Characteristics Adult male (left) and female Tapanuli orangutans The most arboreal 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 75kg (165lb), while females reach about 37kg (82lb). Dominant 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 offspring. Fruit is the most important component of an orangutan's diet; but they will also eat vegetation, bark, honey, insects and bird eggs. They can live over 30years, both in the wild and in captivity.

Chalmeau, Raphaël; Lardeux, Karine; Brandibas, Pierre; Gallo, Alain (1997). "Cooperative problem solving by orangutans ( Pongo pygmaeus)". International Journal of Primatology. 18 (1): 23–32. doi: 10.1023/A:1026337006136. S2CID 44204663. 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.). Orangutans: Geographic Variation in Behavioral Ecology and Conservation. Oxford University Press. p.199. ISBN 978-0199213276. Tan, Peter (October 1998). "Malay loan words across different dialects of English". English Today. 14 (4): 44–50. doi: 10.1017/S026607840001052X. S2CID 144326996. 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). "Land-cover changes predict steep declines for the Sumatran orangutan ( Pongo abelii)". Science Advances. 2 (3): e1500789. Bibcode: 2016SciA....2E0789W. doi: 10.1126/sciadv.1500789. PMC 4783118. PMID 26973868.

Habitat And Origin

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. Orangutans are great apes native to the rainforests of Indonesia and Malaysia. They are now found only in parts of Borneo and Sumatra, but during the Pleistocene they ranged throughout Southeast Asia and South China. Classified in the genus Pongo, orangutans were originally considered to be one species. From 1996, they were divided into two species: the Bornean orangutan ( P. pygmaeus, with three subspecies) and the Sumatran orangutan ( P. abelii). A third species, the Tapanuli orangutan ( P. tapanuliensis), was identified definitively in 2017. The orangutans are the only surviving species of the subfamily Ponginae, which diverged genetically from the other hominids ( gorillas, chimpanzees, and humans) between 19.3 and 15.7 million years ago. The orangutan was first described scientifically in 1758 in the Systema Naturae of Carl Linnaeus as Homo troglodytes. [6] :20 It was renamed Simia pygmaeus in 1760 by his student Christian Emmanuel Hopp and given the name Pongo by Lacépède in 1799. [6] :24–25 The populations on the two islands were suggested to be separate species when P. abelii was described by French naturalist René Lesson in 1827. [16] In 2001, P. abelii was confirmed as a full species based on molecular evidence published in 1996, [17] [18] :53 [19] and three distinct populations on Borneo were elevated to subspecies ( P. p. pygmaeus, P. p. morio and P. p. wurmbii). [20] The description in 2017 of a third species, P. tapanuliensis, from Sumatra south of Lake Toba, came with a surprising twist: it is more closely related to the Bornean species, P. pygmaeus than to its fellow Sumatran species, P. abelii. [19] Flanged male Bornean, Sumatran and Tapanuli orangutans a b 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 ( Pongo sp.) fossils in Peninsular Malaysia: Biogeographic and paleoenvironmental implications". Journal of Human Evolution. 65 (6): 770–97. doi: 10.1016/j.jhevol.2013.09.005. PMID 24210657.