These bones could be the oldest human remains ever found in the Americas. Although they might be a colossally important artifact of anthropological history, most of the skeleton has since been lost to looters and thieves.
The skeleton was first discovered in 2012 by divers exploring the depths of an underwater cave, or cenote, called Chan Hol near Tulúm in Mexico. After photos of the bones were paraded across social media, archaeologists were keen to head to the cave themselves to see what was going on.
However, by the time they got to the site just over a month later, most of the bones had disappeared, presumed stolen. All that remained was 150 small bone fragments and a pelvic bone, about 10 percent of the original skeleton, which had become embedded into the stalagmites over the centuries.
A new study in the journal PLOS One has finally looked at these remaining bones to uncover their story. Researchers dated the skeleton by analyzing the uranium, carbon, and oxygen isotopes found in its fragments and the stalagmite that had engulfed the pelvic bone.
According to this isotopic analysis, the skeleton is over 13,000 years old from the Late Pleistocene era. The cave would not have been filled with water at this time, which would also explain why most of the bones appeared to lie close together in their original anatomical position.
The debate about when humans arrived in the Americas is long, fiddly, and full of controversy. The old consensus was that humans arrived sometime around 13,000 to 14,000 years ago after the Bering Strait thawed, allowing humans to travel from Asia to North America. A more recent update said it was probably close to 24,000 years ago. A controversial study from this year even claimed archaeological evidence suggests there was human activity in the Americas up to 131,000 years ago.
However, for the most part, these dates are based on indirect evidence such as the discovery of tools or scratches on animal bones. So although this skeleton isn't the oldest evidence of humans in the Americas, it is perhaps one of the oldest human skeletons found there.
That said, the researchers note that their dates might not be spot on since changes in climate over time may have influenced the dating of the skeleton. Additionally, being soaked in water for millennia also affects the dating process.
As for further research into this Mexican cave skeleton, it might be pretty tough. Lead researcher Wolfgang Stinnesbeck told Nature that his team sent a sample of the skeleton to the Max Planck Institute for Evolutionary Anthropology in Germany for genetic analysis. However, those remains did not contain enough to DNA to reach any conclusion about the sex and age of the person.
Sadly, scientists or the authorities still don't have any idea where the skeleton is to this day.