The creature shows a surprising mix of human like and more primitive characteristics some experts called it “bizarre” and “weird.”
And the discovery presents some mysteries. How old are the bones? And how did they get into that chamber?
The site, about 30 miles northwest of Johannesburg, has yielded some 1,550 specimens since its discovery in 2013. The fossils represent at least 15 individuals.
The researchers said, the creature, which evidently walked upright, represents a mix of traits. For example, the hands and feet look like Homo, but the shoulders and the small brain recall Homo’s more ape-like ancestors.
The researchers announced the discovery in the journal eLife and at a news conference in the Cradle of Humankind, a site near the village of Magaliesburg.
They said they were unable to determine an age for the fossils because of unusual characteristics of the site, but that they are still trying.
Besides the age of the bones, another mystery is how they got into the difficult to reach area of the cave.
The researchers said they suspect the naledi may have repeatedly deposited their dead in the room, but alternatively it may have been a death trap for individuals that found their own way in.
Not everybody agreed that the discovery revealed a new species.
Tim White of the University of California, Berkeley, called that claim questionable. “From what is presented here, (the fossils) belong to a primitive Homo erectus, a species named in the 1800s,” he said in an email.