WASHINGTON, Nov. 2 (Xinhua) -- A new species of great apes, named the Tapanuli orangutan, has been found in Indonesia, researchers reported Thursday.
Six living species of non-human great apes are currently recognized: Sumatran and Bornean orangutans, eastern and western gorillas, chimpanzees, and bonobos.
But researchers reporting in the journal Current Biology have now made it seven, based on a collection of evidence showing that an isolated population of orangutans in Sumatra is actually its own unique species.
"It isn't an everyday event that we find a new species of great ape, so indeed the discovery is very exciting," senior author Michael Krutzen of the University of Zurich in Switzerland said in a statement.
The new orangutan species lives in the Batang Toru area in North Sumatra, Indonesia.
While there had been rumors, no one was sure that this population of orangutans existed until 1997.
They live south of what had been the known range for Sumatran orangutans.
The first indications of the uniqueness of the new species came from the skeleton of an adult male orangutan killed in 2013.
When compared to other skulls, it turned out that certain characteristics of the teeth and skull of the Tapanuli orangutan were unique.
Bornean and Sumatran orangutans separated only much later, less than 700,000 years ago.
And the newly discovered orangutan species appeared to have been isolated from all other Sumatran populations of orangutans for at least 10,000 to 20,000 years.
Unfortunately, the researchers said, there are only about 800 Tapanuli orangutans left.
"If steps are not taken quickly to reduce current and future threats and to conserve every last remaining bit of forest, a great ape species may become extinct within a few decades," warned Matt Nowak, who supervised research into the Tapanuli orangutans at the Sumatran Orangutan Conservation Program.
