Orangutans are one of the rarest of the great apes, living only in the forests of Borneo and Sumatra. For this reason, it probably wouldn’t have surprised most people to know that orangutans were split into two distinct species; Bornean orangutan and Sumatran orangutan. However, the small island of Sumatra was hiding the Tapanuli orangutan, a secret, third species only recently discovered, entirely distinct from the cousins it shares its home with.
The Tapanuli orangutan, or Pongo tapanuliensis, is the first species of great ape to be discovered in eighty-eight years, the previous discovery being the bonobo chimp. Despite sharing its habitat with the Sumatran orangutan, the National Geographic reported in November 2017 that scientists found the Tapanuli orangutan to be more closely related to its Bornean counterparts. Analysis of the three species found something else very surprising. Out of the three species of orangutan, Tapanuli, the apparent newcomer, is actually the oldest. It had avoided discovery until recently simply by the assumption that all orangutans on Sumatra were of one species.
It was perhaps easier for the Tapanuli orangutan to slip under the radar due to its rarity. While all three species of orangutan are critically endangered, Tapanuli is the rarest. In fact, Tapanuli is the rarest of all species of great apes, a group which also includes chimps, gorillas and humans. With only 800 members of the Tapanuli species in existence, it is remarkable that the species was discovered at all.
Kris Helgen, a mammalogist at the University of Adelaide in Australia, reportedly said that many undiscovered species like Pongo tapanuliensis are endangered and that urgent study needs to be made to find species like this, to help understand them but also to protect them from extinction. The discovery of the Tapanuli orangutan is a wonderful thing, but its scarcity and the danger it faces are also a very real warning. The remarkable creatures on this planet are all too often at risk of dying out and their value can not be overstated. Hopefully, we can still protect the Tapanuli orangutan and find other new species before it’s too late.