Deep within a cave in South Africa, a new discovery has been found that scientists believe will shake up the scientific origins of humanity as we know it.

In an article on scientific journal eLife, scientists recently announced that a new species of human ancestor, called Homo naledi, was unearthed by Professor Lee Berger from the University of Witwatersrand in Johannesburg, South Africa.

The new species, first found in the depths of the limestone tunnels in the Rising Star Cave outside Johannesburg, appears to be very primitive. It has a brain no bigger than the size of an orange, and apelike shoulders for climbing.

Its finger bones are also locked into a curve, indicating that it has used tools. It is also believed to have walked long distances because of its long legs and human-like feet.

The most startling discovery about the Homo naledi, however, goes beyond its physical features. Scientists think that the new species of human ancestors have performed an act that is previously thought to be only limited to humans: burying the dead.

"We have just encountered another species that perhaps thought about its own mortality, and went to great risk and effort to dispose of its dead in a deep, remote, chamber right behind us," Berger said.

"It absolutely questions what makes us human. And I don't think we know anymore what does," he added.

The scientists arrive at this conclusion after they found deep into the cave several fossils of infants, children, adults and elderly individuals—or what seems to be a burial site.

"There is no damage from predators, there is no sign of a catastrophe. We had to come to the inevitable conclusion that Homo naledi, a non-human species of hominid, was deliberately disposing of its dead in that dark chamber. Why, we don't know," Berger explained.

"Until the moment of discovery of 'naledi,' I would have probably said to you that it was our defining character. The idea of burial of the dead or ritualised body disposal is something utterly uniquely human," he added.

Since the fossils were located within the depths of the cave, the scientists also believe that the Homo naledi may have used fire to light up the way and reach this area.

The newly discovered fossils, however, will still have to be dated. At present, the first undisputed human burial dates go back to some 100,000 years ago.

Still, Berger believes that this discovery will change the way we look at human ancestry and humanity forever.

"This is like opening up Tutankhamen's tomb. It is that extreme and perhaps that influential in this stage of our history," he said.