Two years ago Lee Berger recruited people on social media to explore a 7-inch-wide rift in which it was thought that a shipment of human fossils could be found.
More details of the excavation at Rising Star Cave, 50 kilometers from Johannesburg, were released this week.
A chasm with more than 1,500 human fossils has been discovered and researchers say it is a hitherto unknown species within the genus homo which has been baptized as Homo naledi.
Experts believe that those individuals were deposited there by their congeners, which supposes an unexpected funerary-type behavior that had never been observed in such primitive humans.
The site found is the largest set of fossils concentrated in one place in all of Africa.
The researchers explain that they have not been able to date the fossils nor do they know how fifteen bodies could get there. In order to get to the chamber where the hominid remains were found, it is necessary to travel 80 meters, climb a wall and slip through a crevice.
This route, totally dark, is the only one that exists to get there and the only one that existed according to geological studies when the corpses were deposited there.
Due to the size of the bones, it has been determined that there were children, adolescents, adults and the elderly among the corpses and none have marks of trauma from a fall into the grave.
There are no remains of another animal, except birds or mice. The cave does not show signs of intense floods, which could have washed the remains there.
The only hypothesis left is that someone left the remains there, the study authors say. Funeral rituals of this style have hitherto only been attributed to the most modern and brained humans.
“We have almost all the bones of the body represented several times, which makes the Homo naledi it is practically the best known fossil of our lineage, ”explained Lee Berger, a paleanthropologist at the University of the Witwatersrand.
Following the discovery of the remains in October 2013, Berger began selecting a group of international scientists to analyze the body parts of the new species..
The bones were partially fossilized and some were visible to the naked eye on the cave floor.
Analysis of the remains has concluded that the species discovered is not a simple upright chimpanzee. Experts think that gender Homo arose through the australopithecines, but until recently there was a total void of fossils that allowed to confirm it.
Due to the morphology they present, naledi They seem to be on the borderline of both groups, they were five feet tall and weighed about 45 kilos.
They had not yet developed a large brain (500 cubic centimeters), but they already had a slim body and human features, such as the ability to walk upright or small teeth and his hands had the opposable thumb that allows making tools.