Scientists have long recognized six living species of great ape aside from humans: Sumatran and Bornean orangutans, eastern and western gorillas, chimpanzees, and bonobos. But researchers have now made it seven, based on a collection of evidence showing that an isolated population of orangutans living in Sumatra is actually its own unique species. They’ve named the new species the Tapanuli orangutan (Pongo tapanuliensis).