Scientists say the bones discovered in a South African cave two years ago are a previously unknown human ancestor.
The find unearthed more than 1500 bone fragments belonging to at least 15 individuals, revealing the human-like Homo Naledi. Thousands more bones remain in the difficult-to-reach cave.
However, paleoanthropologist Professor Lee Burger says what's most exciting is the bones were found in a burial pit.
"We thought that the idea of ritualised behaviours directed towards the dead was utterly unique to Homo sapiens. We have now seen, we believe, a species that had that same capacity."
With ape-like shoulders and arms, it had legs similar to humans, a brain the size of an orange and stood about 1.5m tall.
Naledi means 'star' in Sesotho, a language from the region.
To get to the bones, researchers had to squeeze through a gap in the rock only 18cm wide. An all-female team was chosen for the task.
Some experts have cast doubt on the find, saying the remains look remarkably like Homo erectus.
"Intentional disposal of rotting corpses by fellow pinheads makes a nice headline, but seems like a stretch to me," says Stony Brook School of Medicine anthropologist William Jungers.
"The 'new species' and 'dump-the-dead' claims are clearly for the media. None of them is substantiated by the data presented in the publications," says University of Zurich anthropologist Christoph Zollikofer.
Instead, they hypothesise the group went in there all at once, perhaps fleeing danger on the outside.
It's not known how old the bones are yet. They weren't encased in rock and no animal remains were found with them.