Human remains are among discoveries in the Sac Actun cave. Ancient remains are among discoveries in the Sac Actun cave.

Human remains found in underwater cave

Flooded Yucatán Peninsula caverns yield discoveries dating back to Ice Age

Archaeologists exploring the world’s largest underwater cave have found ancient human remains among almost 200 discoveries that date back to the last Ice Age.


A team of experts from the National Institute of Anthropology and History (INAH) last month discovered a link between two systems of flooded caverns on the Yucatán Peninsula that together measure 347 kilometers.

But the find didn’t spell an end to work on the ambitious Great Mayan Aquifer (GAM) Project, in which archaeologists, biologists, underwater photographers and cave divers are exploring, documenting and mapping the extensive subterranean network of water deposits.

Exploration of the Sac Actun cave system continued, leading to the discovery of an additional four kilometers of underwater passages as well as 98 new archaeological discoveries, bringing the total number of finds in the network to 198.

Just over two-thirds of that number are relics of Mayan culture while the remainder date back to the most recent Ice Age (2.6 million to 11,700 years ago).

At a press conference yesterday, GAM project director Guillermo de Anda explained the two most significant finds.

“One of them is a well-preserved skeleton, although its parts are dispersed far from the entrance to the cave . . . The other is a concretionary skull that is in the process of being studied . . .” the underwater archaeologist said.


De Anda explained that the latter was found joined to a rock in a cave that has been flooded for the last 8,000 to 10,000 years.

“The remains are very important because they are probably of early, pre-ceramic individuals,” he said.

The new discovery adds to other human remains that were found in the Sac Actun system prior to the start of the current project.

In 2007, the skeleton of a teenage female known as Naia was discovered in the Hoyo Negro, or Black Hole underwater chamber. Her bones are believed to be around 12,600 years old.

In the latest exploration the team also found bones of giant sloths and gomphotheres — an extinct elephant-like mammal — as well as ceramic remains, altars, shrines and wall etchings.  The ceramics were likely used in funeral and human sacrifice ceremonies.

According to INAH, water levels rose at the end of the last Ice Age, flooding the cave system and creating “ideal conditions for the preservation of the remains of extinct megafauna from the Pleistocene.”

“Without a doubt, it’s the most important underwater archaeological site in the world,” de Anda said.

“. . . It allows us to establish clearer hypotheses about human interaction and extinct fauna . . .” he explained.

One of those hypotheses is that human presence in the region dates back 9,000 years, much longer than the 3,000 years previously thought. Another is that the site was part of an ancient Mayan trade route.

“The merchants followed established routes and used these places as ritual pilgrimage points, they made stops at altars and sacred sites to make an exchange with the gods and they’ve left their mark there,” de Anda said.

Further discoveries are likely to follow as the GAM team continues to navigate the extensive subterranean cave network looking for more links with other systems that could make the world’s largest underwater cave even bigger.

“We’re getting ready [to explore] another connection with another system, Kook Baal, that is 93 kilometers long. We’re going to explore another 20 kilometers of passages to make the connection so the cave will reach 500 kilometers,” said Robert Schmittner, the leader of the GAM exploration team.

“In Quintana Roo, there are 1,400 kilometers of caves in 358 different systems that are relatively close to each other; we plan to make connections that give us more than 1,000 kilometers in total,” he added.

Source: Milenio (sp)

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