Scientists have discovered a new human-like species in a burial chamber deep in a cave system in South Africa.
Discovery of 15 partial skeletons is the largest single discovery of its type in Africa.
Researchers claim that the discovery will change ideas about our human ancestors.
Studies which have been published in the Elife also indicate that these individuals were capable of ritual behaviour.
The species, which has been named naledi, has been classified in the grouping, or genus, Homo, to which modern humans belong. Researchers who made the find have not been able to find out how long ago these creatures lived - but the scientist who led the team, Prof Lee Berger, told BBC News that he believed they could be among the first of our kind (genus Homo) and could have lived in Africa up to three million years ago.
Ardipithecus ramidus (4.4 million years ago) : Fossils were discovered in Ethiopia in the 1990s. Pelvis shows adaptations to both tree climbing and upright walking.
Australopithecus afarensis (3.9 - 2.9 million years ago) : The famous "Lucy" skeleton belongs to this species of human relative. So far, fossils of this species have only been found in East Africa. Several traits in the skeleton suggest afarensis walked upright, but they may have spent some time in the trees.
Homo habilis (2.8 - 1.5 million years ago) : This human relative had a slightly larger braincase and smaller teeth than the australopithecines or older species, but retains many more primitive features such as long arms.
Homo naledi (Of unknown age, but researchers say it could be as old as three million years) : The new discovery has small, modern-looking teeth, human-like feet but more primitive fingers and a small braincase.
Homo erectus (1.9 million years - unknown) : Homo erectus had a modern body plan that was almost indistinguishable from ours. But it had a smaller brain than a modern person's combined with a more primitive face.
Homo neanderthalensis (200,000 years - 40,000 years) The Neanderthals were a side-group to modern humans, inhabiting western Eurasia before our species left Africa. They were shorter and more muscular than modern people but had slightly larger brains.
Homo sapiens (200,000 years - present) Modern humans evolved in Africa from a predecessor species known as Homo heidelbergensis. A small group of Homo sapiens left Africa 60,000 years ago and settled the rest of the world, replacing the other human species they encountered (with a small amount of interbreeding).
"The first time I went to the excavation site I likened it to the feeling that Howard Carter must have had when he opened Tutankhamen's tomb - that you are in a very confined space and then it opens up and all of a sudden all you can see are all these wonderful things - it was incredible," she said.
Ms Elliott and her colleagues believe that they have found a burial chamber. The Homo naledi people appear to have carried individuals deep into the cave system and deposited them in the chamber - possibly over generations.
If that is correct, it suggests naledi was capable of ritual behaviour and possibly symbolic thought - something that until now had only been associated with much later humans within the last 200,000 years.
