Did you know that orangutans share about 97% of their DNA with humans? This close genetic relationship not only makes them fascinating from a scientific perspective but also highlights their special place in the natural heritage of Southeast Asia.
Interestingly, there are only three species of orangutans in the world—and all of them are found in Indonesia, with a small portion inhabiting Malaysia. About 85% of the global orangutan population lives in Indonesia, primarily in the rainforests of Sumatra and Borneo. The rest, around 15%, can be found in the Malaysian states of Sabah and Sarawak.
The three orangutan species are the Bornean orangutan (Pongo pygmaeus), the Sumatran orangutan (Pongo abelii), and the Tapanuli orangutan (Pongo tapanuliensis). Among them, one stands out as the rarest.
Understanding the Three Orangutan Species
Each species has its own distinct traits: physically, behaviorally, and ecologically.
The Bornean orangutan, found across the island of Borneo including parts of Malaysia, is generally larger in size, has dark brown hair, and tends to be more solitary. Their diet is quite varied, consisting of fruits, leaves, insects, and even small animals such as slow lorises.
The Sumatran orangutan, on the other hand, is slimmer with striking reddish-brown hair. They are mainly found in northern Sumatra and are known to be more social than their Bornean cousins. Sumatran orangutans are also impressively intelligent, capable of using simple tools to obtain food.
But the most extraordinary of them all is the Tapanuli orangutan, the newest and rarest member of the great ape family, scientifically identified only in 2017. This discovery marked the first addition to the great ape family in over a century.
Meet the Tapanuli Orangutan: The World’s Rarest Great Ape
The Tapanuli orangutan inhabits only one place on Earth: the highland rainforest of the Batang Toru ecosystem in North Sumatra, Indonesia. Though their existence was known as early as the late 1990s, they were not officially recognized as a distinct species until detailed research was conducted on their genetics, morphology, ecology, and behavior.
But what truly sets this orangutan apart is its incredibly limited range and critically low population size. According to WWF data, only about 800 individuals remain, making the Tapanuli orangutan the rarest great ape on Earth.
Physically, the Tapanuli orangutan is slightly smaller than its Bornean and Sumatran cousins. It has a flatter, wider face, with thick, curly cinnamon-colored hair. Mature males are especially distinctive, sporting long beards, striking mustaches, and flat cheek pads fringed with pale, wispy hair.
Their long-distance calls are also unique—longer and higher-pitched than those of Bornean orangutans, yet different from the deeper, prolonged calls of their Sumatran relatives. In terms of diet, Tapanuli orangutans consume rare plant species, such as Aturmangan seeds and fruits from the Podocarpaceae and Araucariaceae families—items not typically eaten by other orangutans.
Despite their scientific and ecological significance, the Tapanuli orangutans are facing an existential threat. For comparison, there are approximately 104,700 Bornean orangutans and 13,846 Sumatran orangutans—making the 800 remaining Tapanuli individuals an alarming conservation emergency.
On the Brink: The Alarming Fate of the Orangutan
Orangutans, the only great apes native to Asia, are now facing an increasingly dire threat of extinction. All three species, the Bornean, Sumatran, and Tapanuli orangutans, are classified as critically endangered by the IUCN. Their populations have plummeted due to widespread habitat destruction, illegal hunting, and mounting pressure from large-scale infrastructure development.
This crisis is worsened by the orangutan’s extremely slow reproductive rate. A female typically gives birth to only one offspring every 8 to 9 years. Without significant changes in conservation efforts—including stronger policies, better habitat protection, public education, and stricter law enforcement—these incredible creatures, who have shared the Earth with us for millions of years, may disappear in the not-so-distant future.
