Original sentence: The group gained international fame in the 1970s when the media reported that they had been living in isolation since the Stone Age.This was later discovered to be a hoax.tribe) within the deep and mountainous rainforests of the southern Philippine island of Mindanao
Edited sentence: tribe) of the deep and mountainous rainforests of the southern Philippine island of Mindanao who, up until the mid-20th century, were living as close to Stone Age lifeways as any people known in modern times