On August 30, 2017, new light was shed on the remains of a very old skeleton found in the Chan Hol cave near Tulum in the Yucatan Peninsula of Mexico. A team had been working with what was left behind of a human skeleton after looters plundered the remains. The skeleton was originally discovered in 2012 and showcased on social media. With this publicity, looters quickly located the skeleton and removed it from its grave before researchers could reach the scene a month after its initial discovery.
A team led by Wolfgang Stinnesbeck, paleontologist, and geoscientist at the University of Heidelberg, has been working with what was left behind, which was about 10 percent of the skeleton, to determine the age of the remains.
From their research, it is hypothesized that the skeleton may actually be around 13,000 years old, which would put the skeleton among the oldest found in the Americas. Such a discovery further loosens the foundation of theories on the date when humans first came to the Americas, suggesting they lived on this part of the continent much earlier than scientists previously assumed.
If it is true that the bones are a minimum of 13,000 years old, then it is one of the oldest human remains discovered on North American soil. It is speculated that humans came over by use of the Bering Strait, but with these dated remains continuing to show up, it may turn out that such a migration only increased the population, and did not begin it. Underwater caves such as Chan Hol are promising locations due to the preservation of the water that engulfed the deceased. At one time, these caves were not submerged, allowing interactions among the people of the time. However, the melting of the earth’s ice led to a rising sea level, which, thankfully, also led to the preservation of these gems of the past.
In addition to this skeleton, other ones have been found in similar caves. Not far away, the remains of a possible teenager were found and dated to between 12,000 and 13,000 years ago. Suggesting even older signs of human life, artifacts such as tools have been located and dated to about 14, 500 years old, according to LiveScience. With the continued upheaval of discovery of these old remains, scientists are rethinking the age of mankind in the Americas. Not all of the evidence is convincing, though. Jim Chatters, an archaeologist from Bothell, Washington, suggests that the recent remains may very well be 11,000 years old, but it is not convincing enough to suggest they are 13,000 years old.
Having the skeleton removed from the cave before proper examination of the site caused serious problems regarding the find, which is becoming an ongoing issue regarding caves that are accessible to divers. However, the team decided to try anyway. They found that roughly 10 percent of the skeleton remained, because of the rocks and a stalagmite growing over it. The scientists extracted the human remains they detected.
One of the problems that had to be overcome is the difficulty with carbon dating. It is a popular procedure to determine the age of skeletons by looking at the changes of the isotopes of carbon in dead organic material. If the researchers could have used this method, the dating of the remains would have been easier and possibly more supportable. However, this procedure could not be completed due to inaccurate results. The skeleton had been submerged in water, stripping it of the collagen, making the dating through this method impossible.
To overcome this hurdle, the researchers decided to take advantage of the stalagmite growing over the pelvic region of the bones. Samples were taken from this and surrounding rocks to study isotopes in these materials. By doing this, they could date the surrounding environment to gain insight into the age of the skeleton.
The tests suggest that the stalagmite is over 11,000 years old. With this information, the researchers attempted to place the age of the skeleton. There are deposits of sediment under the stalagmite that suggest some time had passed before it formed. With all of this information, scientists hypothesize that the bones may be as old as 13,000 years. In addition, with the help of the images taken before the disappearance of the majority of the remains, researchers believe the skeleton belongs to a male.
For now, researchers have already published their findings up to the 30th of August 2017, and will likely continue to attempt to place the age of the remains. The findings are published in the PlOS One journal, which can be read online. Until more evidence is put forward, some scrutiny will remain concerning the technique used to find the skeleton’s age.