Orangutans are great apes classified in the genus Pongo. They are the only extant genus of the subfamily Ponginae. All other genera under Ponginae were extinct : Lufengpithecus, Ankarapithecus, Sivpithecus, Gigantopithecus, Khoratpithecus.
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). In 2017, a third species, the Tapanuli orangutan (P. tapanuliensis), was identified.
All three orangutan species are considered critically endangered in the IUNCR Red List.
Etymology
The name "orangutan" is derived from the Malay words orang, meaning "man", and hutan, meaning "forest". The word was first attested in English in 1691 in the form orang-outang.
The orangutan was first described scientifically in 1758 in the Systema Naturae of Carl Linnaeus as Simia satyrus. It was renamed Simia pygmaeus in 1760 by Christian Emmanuel Hopp.
The name of the genus, Pongo, comes from a 16th-century account by Andrew Battel, an English sailor held prisoner by the Portuguese in Angola, which describes two anthropoid "monsters" named Pongo and Engeco. He is now believed to have been describing gorillas. French naturalist Bernard Germain de Lacépède used the term Pongo for the genus in 1799.
Phylogeny
In 2011, the Sumatran orangutan, following humans and chimpanzees, became the third species to have its genome sequenced. Subsequently in 2017, the Bornean and Tapanuli species had their genome sequenced.
Orangutans have 48 diploid chromosomes, in contrast to humans, which have 46.
Orangutans travelled from Sumatra to Borneo as the islands were connected by land bridges as parts of Sundaland during recent glacial periods 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.
Taxonomy of Pongo |
● Pongo hooijeri† |
● Pongo weidenreichi† |
● Pongo pygmaeus |
● Pongo
pygmaeus pygmaeus – Sabah |
● Pongo
pygmaeus morio – Sarawak |
● Pongo
pygmaeus wurmbii – Kalimantan |
● Pongo abelii -
Sumatra |
● Pongo tapanuliensis–
Sumatra |