Inside the Claustrophobic Underground Caves Where the New Species of Ancient Human Was Discovered

Dr. Marina Elliott had no idea what kind of adventure lay in store when she decided to answer a Facebook post that sought people with excellent archaeological excavation skills. The ad, which was posted in the fall of 2013, didn't list a specific location, but it did mention that those who answered needed to be "skinny and preferably small." Elliott was intrigued. The ad had been posted by Lee Berger—a paleoanthropologist at the University of the Witswatersrand in South Africa.

Encouraged by her supervisor at Simon Fraser University in BC, Elliott responded and conducted a Skype interview with Berger.

Three weeks later, her plane touched down in Johannesburg.

From 60 qualified international applicants, Berger had assembled a team of six women. In addition to Elliott, a Canadian who had just completed her PhD in biological anthropology, there were four Americans—Hannah Morris, Alia Gurto, K. Lindsay Hunter, Becca Peixotto—and one Australian, Elen Feuerriegel.

They were indeed all small, an essential quality for the task ahead, which involved squeezing into a series of underground cavities inside the Rising Star Cave, including one narrow point only 18 centimeters (just under eight inches) wide.

What the team didn't yet know was that they were walking (or rather, crawling) into the groundbreaking discovery of Homo naledi, an entirely new species of human relative. It was also a find that would prove to be unusually rich: the single largest deposit of ancient hominin fossils yet uncovered on the entire continent of Africa. The huge discovery is being featured in the October issue of National Geographic.

"I think all of us that managed to end up on the project literally spent time stuffing ourselves under the furniture in our houses to see if we could get into an 18-centimeter gap," Elliott told me with a laugh.

At 46, she was one of the most experienced cavers on the team, a factor that may have inspired Berger to ask her to lead the first crew into the space, located 82 feet below the surface of the earth.

It was early November when an above-ground support network of more than 50 scientists, cavers, and experts gathered at the site, about 30 miles northwest of Johannesburg, in a wider world heritage site famously known as "the cradle of humankind" for its large deposits of ancient human fossils.

All that was known prior to the initial descent was what had been gleaned from the reports and photos from cavers Rick Hunter and Steve Tucker, who made the initial discovery.

Berger, already known for his 2008 discovery of hominin Australopithecus sediba in nearby Malapa Cave, suspected the Rising Star cave system might harbor a specimen of another, yet unknown, ancient human relative.

Essential to the quest to find out for certain would be this team, clad in blue jumpsuits and helmets, affectionately referred to as the "underground astronauts."

The cave had never produced ancient fossil material in the past, and they thought it was likely a salvage operation of one skeleton, said Elliott.

"Really, we all thought that this was just going to be kind of a one-off thing. That we would go, we would excavate this thing, and we'd be done. I don't think any of us thought it would be an ongoing project," she added. "But then it just became so much more."

From the beginning, she was briefed on the cave's high-risk environment. If an injury occurred, even a twisted ankle, rescue could become a major problem.

"It was a very, very physical exercise to go from the surface to the excavation chamber. It's very physically demanding. And you're also then adding on the fact that it's pitch black so if you have a technical problem and your light goes out, then you're kind of… in the middle of nothing," said Elliott. "You need both hands, both legs, and all your faculties to negotiate that system."

Minimally armed with CO2 monitors, lights, excavation gear, and harnesses, Elliott and team members Morris and Peixotto prepared to enter the cave.

Among the more difficult sections included a squeeze called "Superman's crawl" and another jagged, nearly vertical section they dubbed the "dragon's back."

"It's in an area called 'the chute,' which is actually a 12-meter-deep [39-feet] crack in the rock, it's kind of a long fissure, so 18 centimeters is the depth that you need to be able to squeeze through. You've got room on either side of your shoulder but you have rock right at your nose and right at your back," said Elliot. "You can't really see down, because you can't turn your head to look down below you. You just have to kind of feel."

It was this final section she had to negotiate before first emerging into the final space they were seeking: Dinaledi, or the chamber of stars.

"I am a bit of a history buff and I love the Age of Discovery writing, and so when I was actually working my way through the system and finally knew that I was about to enter the excavation chamber itself, it's quite a tight hallway you have to slither through, and I remember thinking, as I squeezed past this final section into the final chamber: This was what Howard Carter must have felt like when he opened Tutankhamun's tomb. Because the story of him doing that has these pencil sketches and there's someone in the background saying, 'Carter, what do you see?' and he's peeking through this hole and he says 'Things, I see wondrous things,'" she said.

As she entered the room, Elliott glanced about with her headlamp. All she could see were flashes of bone, everywhere, all over the floor of the chamber.

"I thought, Holy crackers, what is this? Wow, this is not what I signed up for. This is going to be a bit crazy. It really was one of those combinations of exhilaration and kind of, oh, maybe a little bit of terror? Like, I don't know, man, I don't think you guys knew what you were getting into," she said with a laugh.

The team began uncovering huge amounts of material, 50 to 80 fragments a day, a density of material that archaeologists often don't recover in decades of work, said Elliott.

So far they have amassed more than 1,550 fossils from 15 individuals of the same species which span in age from infants to the elderly.

Though they are certain that Homo naledi walked upright, there was no evidence within the cave of tools or fire implements, and it didn't appear to be a living space.

It's also unknown how the bodies—which are not accompanied by flora or fauna or show any evidence of being dragged there by animals—ended up in the chamber. Berger said they suspect they were intentionally placed there, a behavior that until now was thought to be the sole domain of humans.

Unusually, Berger and the entire support team not only shared their findings via social media as the excavation went along, they also deliberately decided to release their findings through a peer-reviewed, open-access, non-profit scientific journal called eLife, to make the information as accessible as possible.

"Marina, along with the other underground astronauts are, in my opinion, heroic," said Berger via email. "The guts it took to drop everything and come to South Africa in order to recover fossils in such a dangerous situation is something I shall admire for the rest of my life. I hope their actions and exemplary modeling of what it means to be a modern day explorer inspires a generation of young men and women to themselves become explorers."

Work at the site continues and new fossils are still being excavated, said Elliott, who spoke with VICE from South Africa. It will likely take decades before the significance of all the material is fully understood, she added.

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