For two nights at the end of August, Casa-Cem’s modest “conversation salon” was filled beyond capacity by Tapatios anxious to see photos and videos of the dramatic discovery of the oldest human skeleton ever found on the American continent.
The crowds quickly learned that the presenter, Roberto Chávez, co-director of Proyecto Arqueológico Subacuático Hoyo Negro, was just as interesting as the audio visuals and quite willing to answer the audience’s many questions well beyond the limits of the programmed time slot. “This was a marvelous presentation about an extraordinary discovery made in Mexico,” said biologist Rodrigo Orozco, “but the greatest surprise was that hardly a soul in the room had ever heard about it.”
All the excitement was over a discovery made in the Aktun-Hu Cave System in 2007 by Alejandro “Alex” Álvarez, Alberto “Beto” Nava and Franco Attolini, members of PET (Projecto Espeleológico de Tulum), an organization that specializes in the exploration and survey of underwater caves on the Yucatan Peninsula. For years, these scuba divers have been systematically mapping Quintana Roo’s water-filled caves (to the tune of over 220 kilometers of passages to date). Cave diver Beto Nava recalled the day a routine mapping trip made history:
“We started the exploration while following the main tunnel and progressed relatively fast by using scooters to cover more terrain. After about 450 meters we began to see the light of another entrance, so we headed towards it and surfaced. After taking a moment to chat and laugh about what a great dive we were having, we dropped down to continue the work.
“After about 120 meters the tunnel narrowed to form a circular shape, almost like a huge cement pipe ... all I could see was the whiteness of the cave walls along the sides, and beyond that it was all black. I thought to myself that this is either the largest tunnel I have seen or there is something unusual at the end of it.
“We continued for another 60 meters and eventually reached the end of the tube-shaped tunnel. To our surprise the floor disappeared and all we could see was blackness in all directions. It felt like we had reached a big drop-off or the edge of a canyon wall.
“We tried to slow down our heart rates as we were not really sure of what to do next.”
The premonition felt by the divers turned out to be true. The Hoyo Negro (Black Hole) they had found at the end of the pipe-like passage was a deep pit filled with the bones of ice-age animals like, giant bears and sloths, sabre-toothed cats and gomphotheres (an ancestor of the elephant), all of which had probably smelled water inside the cave, followed the pitch-black tunnel and ended up falling over the sheer edge of the 60-meter-deep pit (which probably contained a certain amount of rainwater in ancient times) now named Hoyo Negro.
It was a trap, a sort of La Brea Tar Pit without the tar. But the big discovery was that in Pleistocene times the pit had also claimed a human victim, a teen-age girl whose skull the divers had found lying at the very top of the heap of bones. Studies revealed that she was 15 or 16 years old and the divers decided to name her Naia, Greek for Water Nymph, and for some she has become Princess Naia.
Over the years, parts of Naia’s skeleton were recovered from the pit – but just how long ago did she fall to her death?
Calcite particles which adhered to the bones helped in the painstakingly slow dating process, but it wasn’t until May of 2014 that an article in the journal Science declared Naia’s to be the oldest, most complete skeleton ever found in the Americas, around 13,000 years old.
This find, says Glenn Hodges in a National Geographic article, complements the discovery of the 12,600-year-old remains of an infant, found at the Anzick Clovis site in Montana, United States. DNA found in the two skeletons suggest that Paleoamericans came from Asia and are genetically related to native peoples alive today.
Archaeologist James Chatters speculates in the Science article that evolutionary processes may have changed the morphology of Americans over the eons, in an attempt to explain why Naia looks much more like an African than a Maya. Chatters says the next step will be an attempt to decode Naia’s complete genome.
Most of the bones found in the Black Hole are still there, under the protection of the National Institute for Anthropology and History (INAH), but, because they are so unique, Naia’s remains have been removed, to be one hundred percent sure nothing happens to them. “Normally we make every attempt to work in situ,” said INAH archaeologist Pilar Luna.
Experts say a lot more samples of ice-age skeletons are needed to shed light on the history of native Americans. Without a doubt, cave divers like Beto Nava will be searching the floors of Yucatan’s flooded caves with more care than ever before. For him, the discovery of Naia’s skeleton wasn’t just spectacular, “It was the Holy Grail of underwater cave exploration.”