Thousands of years ago, the now-flooded caves deep beneath Mexico’s Yucatán Peninsula served as passageways for the humans and animals of the last Ice Age.
But, for many unfortunate creatures, the journey across the horizontal passage ended in untimely death at the bottom of an inescapable pit.
Divers investigating the notorious pit dubbed ‘Hoyo Negro’ (or, Black Hole) have recovered a trove of bones dating back roughly 13,000 years, revealing the remains of several Pleistocene species – and even the remains of Naia, a 15 year old girl who is the most complete early human ever found in America.
Thousands of years ago, the now-flooded caves deep beneath Mexico’s Yucatán Peninsula served as passageways for the humans and animals of the last Ice Age. But, for many unfortunate creatures, the journey ended in untimely death at the bottom of an inescapable pit
Among the bones recovered so far were three different types of giant ground sloth, one of which is now said to be an entirely new species.
They also found the remains of short-faced bears, mountain lions, sabertooth cats, the elephant-relative gomphothere, and tapirs.
And, alongside the Pleistocene megafauna, the divers discovered the ‘most complete early human skeleton,’ found yet in the Americas.
The team, who is set to present the findings at this years’ at the annual Society of Vertebrate Paleontology in Calgary, Alberta (Canada) on Saturday, says the remarkable discovery offers new insight on life at the end of the last Ice Age.
‘This represents the oldest and most complete early human skeleton in the Americas, and she co-existed with a variety of megafauna,’ Schubert said. The skull of the human, dubbed Naia, can be seen at the site above
Divers investigating the notorious pit dubbed ‘Hoyo Negro’ (or, Black Hole) have recovered a trove of bones dating back roughly 13,000 years, revealing the remains of several Pleistocene species. Pictured above, a diver can be seen alongside the arm bones of giant ground sloth
Leading up to the extraction of the bones, the divers photo-documented the site, taking special precautions to prevent damage.
The researchers even used re-breathing SCUBA equipment to ensure their bubbles wouldn’t disturb the remains.
‘[The] preservation of the fossil material is extraordinary, and will allow us to reconstruct various aspects of anatomy, evolutionary relationships, and behaviour,’ said Dr Blaine Schubert of East Tennessee State University, one of the lead researchers.
‘NAIA,’ AMERICA’S OLDEST NEAR-COMPLETE SKELETON
Deep in an underwater cave in Mexico, researchers discovered what’s said to be one of the world’s oldest complete human skeletons.
The girl’s nearly complete skeleton was discovered by chance in 2007 by expert divers who were mapping water-filled caves north of the city of Tulum, in the eastern part of the Yucatan Peninsula.
She plunged to her death in a large pit known as ‘Hoyo Negro’, Spanish for ‘black hole’, in Mexico’s Yucatan Peninsula.
Several studies following her discovery have shed new light on the life of the teenage girl, named ‘Naia.’
Experts say she was 15-16 years old at the time of her death, when she went underground to seek water 13,000 years ago during the last Ice Age.
Researchers add that she was about five feet (1.5 meters) tall and weighed about 110 pounds (50 kilograms) at her heaviest, though there was evidence she had suffered episodes of famine.
She had broken her arm but it later mended.
And, a study released in March 2017 suggests she may have recently given birth before she died.
During the time she roamed Earth, the now flooded cave systems were much the same, apart from the water level being much lower than it is now.
Her almost complete remains, including an intact skull and preserved DNA, were lying 130 feet below sea level near a variety of extinct animals, such as an elephant like creature called a gomphothere.
The girl’s nearly complete skeleton was discovered by chance in 2007 by expert divers who were mapping water-filled caves north of the city of Tulum, in the eastern part of the Yucatan Peninsula. Researchers have since been working to preserve the remains
‘The diversity of the fauna gives us an exciting new picture of this region in the midst of rapid climatic and environmental change.’
During the last Ice Age, the sea level was much lower, allowing the animals and humans to traverse the passageway.
The remains at the bottom of Hoyo Negro now offer a rare peek into the ‘in-between environment’ of Central America and southern Mexico, according to the researchers.
After the Panamanian land bridge formed around 3 million years ago, this region stood as a middle point between life in North and South America.
Among the bones recovered so far were three different types of giant ground sloth (illustrated right), one of which is now said to be an entirely new species. They also found the remains of short-faced bears (illustrated left), mountain lions, and sabertooth cats
Alongside the Pleistocene megafauna, the divers discovered the ‘most complete early human skeleton,’ found yet in the Americas. Pictured above, a diver can be seen near the skull of an ancient human, dubbed Naia
Both the human and animal remains now help to paint a clearer picture of the biotic interchange that took place at the site.
‘This represents the oldest and most complete early human skeleton in the Americas, and she co-existed with a variety of megafauna,’ Schubert said.
‘The remains of the short-faced bear Arctotherium are particularly significant, representing not only the most complete and abundant material from one location, but also the first evidence that they crossed from South America into North America.’
THE ‘BLACK HOLE’ BENEATH MEXICO
About 12,000 years ago Earth experienced a great climactic change, when the melting of the ice caps caused a dramatic rise in global sea levels, which flooded low lying coastal landscapes and cave systems.
Many of the subterranean spaces that once provided people and animals with water and shelter became inundated and lost until the advent of cave diving.
James Chatters has said in the past: ‘Hoyo Negro is a more than 100-foot-deep, bell-shaped, water-filled void about the size of a professional basketball arena deep inside a drowned cave system.
The remains were found inside a cave called Hoyo Negro (pictured), or black hole
‘Only technical cave divers can reach the bottom.
‘First they must climb down a 30-foot ladder in a nearby sinkhole; then they swim along 200 feet of tunnel to the pit rim before making a final 100-foot drop.’
Like nearby caves, Hoyo Negro was accessible only via sinkhole; people and animals fell in and were trapped.
Then, starting about 10,000 years ago, global glaciers melted, filling the caves with water.
In addition to the near-complete human skeleton, the researchers found the remains of 26 large mammals, including extinct taxa such as sabertooths and gomphotheres.
During the last Ice Age, the sea level was much lower, allowing the animals and humans to traverse the passageway. The remains at the bottom of Hoyo Negro now offer a rare peek into the ‘in-between environment’ of Central America and southern Mexico