Nepedia
Back to Discover
Advanced Reader
🧬

Orangutan

life science Maturity 9-11 Next article →

Orangutans are great apes native to the tropical rainforests of Indonesia and Malaysia.

Bornean, Sumatran & Tapanuli orangs (horizontal)
Bornean, Sumatran & Tapanuli orangs (horizontal)

They belong to the genus Pongo. These primates are the only surviving members of the subfamily Ponginae. This specific lineage diverged from other hominids, such as humans, chimpanzees, and gorillas, between 19.3 and 15.7 million years ago. Today, orangutans are found only on the islands of Borneo and Sumatra. They are highly intelligent animals that spend most of their lives in trees. This makes them the most arboreal of all the great apes.

Orangutans exhibit significant sexual dimorphism, which means males and females look very different.

Pongo tapanuliensis male female
Pongo tapanuliensis male female

Females are generally smaller and weigh less than males. Adult males develop large cheek pads known as flanges. These flanges are made mostly of fatty tissue and are supported by facial muscles. Mature males also possess a prominent sagittal crest on their skulls. They have large throat pouches that act as resonance chambers. These pouches allow them to make long calls to attract females or intimidate rivals. Younger subordinate males do not develop these features and look more like females.

Scientists divide orangutans into three distinct species. The first is the Bornean orangutan, or Pongo pygmaeus, which includes three subspecies. The second is the Sumatran orangutan, or Pongo abelii. The third species is the Tapanuli orangutan, or Pongo tapanuliensis.

Pongo tapanuliensis male female
Pongo tapanuliensis male female

This third species was definitively identified in 2017. Interestingly, the Tapanuli species is more closely related to Bornean orangutans than to Sumatran ones. While they were once thought to be a single species, molecular evidence helped clarify these differences. The Sumatran orangutan genome was even sequenced in January 2011. This made them the third great ape species to have its genome mapped.

Physical adaptations help orangutans thrive in the forest canopy.

Orang-Utan Tournai
Orang-Utan Tournai

They have proportionally long arms and much shorter legs. A male's arm span can reach about 2 meters. Their bodies are covered in long, reddish-brown hair. This hair can range from bright orange to dark maroon or chocolate as they age. Their hands feature four long fingers and a very short opposable thumb. This structure provides a strong grip for moving through branches. They also build elaborate sleeping nests every night using branches and foliage.

History and discovery have shaped our understanding of these apes.

Birute Galdikas
Birute Galdikas

The name "orangutan" comes from the Malay words for "person" and "forest." The first printed English mention was by John Bulwer in 1693. Carl Linnaeus first described them scientifically in 1758. In more recent history, primatologist Biruté Galdikas pioneered important field studies. Orangutans have also been kept in captive facilities since at least the early 19th century. They have appeared in literature and art since the 18th century to comment on human society.

Orangutans face severe threats that have made them critically endangered.

Riau palm oil 2007
Riau palm oil 2007

Human activities have caused massive declines in their populations. Habitat destruction and deforestation are major issues. This often happens because of logging and palm oil cultivation. Poaching for bushmeat is another serious threat. The illegal pet trade also harms wild populations. Because of these pressures, many conservation organizations now work to protect them. They aim to ensure the survival of these primates in their natural homes.

Understanding orangutans connects us to the broader history of life on Earth.

Sivapithecus sivalensis
Sivapithecus sivalensis

Their fossil record includes extinct relatives like Sivapithecus, which lived in India and Pakistan. During the Pleistocene, orangutans had a much larger range. They lived throughout Southeast Asia and South China. They moved between islands via land bridges when sea levels were lower. Today, studying their genetics helps scientists learn about human genetic diseases. They also help us understand how different species evolve and diverge over millions of years.

608 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (16)
File:Bornean, Sumatran & Tapanuli orangs (horizontal).jpg
Bornean, Sumatran & Tapanuli orangs...
File:Sivapithecus sivalensis.JPG
Sivapithecus sivalensis.JPG
File:Pongo tapanuliensis male female.jpg
Pongo tapanuliensis male female.jpg
File:Orang-Utan Tournai.jpg
Orang-Utan Tournai.jpg
Video wild orangutan Borneo.webm
File:Orangutan -Zoologischer Garten Berlin-8a.jpg
Orangutan -Zoologischer Garten Berlin-8a.jpg
File:Leuser-orangs 09N8683.jpg
Leuser-orangs 09N8683.jpg
File:Bukit Lawang, orangutans (6785217748).jpg
Bukit Lawang, orangutans (6785217748).jpg
File:Bornean Orangutan in nest.jpg
Bornean Orangutan in nest.jpg
Orangutanspeech.webm
File:Orangutan using precision grip.jpg
Orangutan using precision grip.jpg
File:Birute Galdikas.jpg
Birute Galdikas.jpg

+ 4 more

More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.