The Sixth represent the first homo sapien sapien, but in raw form.
The Sixth Ancestor, Enok, created them, with help from the other Ancestors, but not the other tribes.
The Ancestors were closing on their goal of creating human kind in their own image, and in a form highly adapted to life on planet Earth.
The Sixth represent the earliest form of homo sapien sapien. Their survival strategy against the Great Ogre was to separate, live singularly, or in small family groups; similar to bears.