Scientists have identified a bearded and frizzy-haired species of orangutan as the latest addition to the family of great apes.

Prior to the recognition of these orangutans living in Indonesian forest, there are seven living species of great apes that biologists recognize, namely humans, chimpanzees, bonobos, eastern gorillas, western gorillas, Sumatran orangutans, and Bornean orangutans.

New Species Of Great Ape

In a paper, which was published in the journal Current Biology on Nov. 2, researchers identified Tapanuli orangutan (Pongo tapanuliensis) as a new species of great ape after comparing its skeleton and genomes to those belonging to other orangutan species.

The researchers also noted of the distinguishing physical features of the species that differentiate them from other species of orangutans. They have frizzier hair and smaller head. They also have other distinct behaviors and characteristics such as the restriction of habitat to the upland areas, diet, and the long call of the males.

"I was surprised about the extent to which the Tapanuli orangutans differed genetically, morphologically as well as behaviourally from the Sumatran and Bornean orangutans," said Marina Davila-Ross, from the University of Portsmouth.

Critically Endangered

The Tapanuli is the first new great ape to be described for nearly a century. Unfortunately, it will also be added to the list of critically endangered species.

The researchers said that fewer than 800 of these orangutans roam a patch of 1,000 square kilometers in the island of Sumatra, Indonesia. With its current known population, researchers contend that the Tapanuli is the most endangered of all surviving great apes.

The species' habitat is under threat. The construction of hydropower plant set to be completed in 2022 may flood up to 8 percent of the species' habitat. It may block the forest corridors that the animal used to move between populations as well, and this could lead to inbreeding and more isolation. Hunting is also one problem that threatens the species.

"A combination of small population size and geographic isolation is of particularly high conservation concern, as it may lead to inbreeding depression and threaten population persistence," the researchers wrote in their study. "Highlighting this, we discovered extensive runs of homozygosity in the genomes of both P. tapanuliensis individuals, pointing at the occurrence of recent inbreeding."

The researchers noted that any drop in number will take years to regain since the females of the species often give birth to only one baby every six years.