Teen’s death sheds light on an American mystery
Thousands of years ago, a teenage girl fell into a deep hole in a Mexican cave and died. That’s certainly a horrible way to die, but her death is now helping us learn more about the past.
Her skeleton and her DNA, the chemical code that makes us what we grow into, are confirming a long-held theory that humans arrived in the Americas by way of a land bridge from Asia, scientists say.
The girl’s nearly complete skeleton was discovered in 2007 by expert divers who were mapping water-filled caves in the eastern part of the Yucatan Peninsula. One day, they came across a huge chamber deep underground.
“The moment we entered inside, we knew it was an incredible place,” one of the divers, Alberto Nava, told reporters. “The floor disappeared under us and we could not see across to the other side.”
They named it Hoyo Negro, or black hole.
Months later, they returned and swam to the floor of the 100-foot tall chamber, which was littered with animal bones. They came across the girl’s skull on a ledge, lying upside down “with a perfect set of teeth and dark eye sockets looking back at us,” Nava said.
The divers named the skeleton Naia, after a water creature of Greek mythology, and joined up with scientists to research the find.
Who was she? The girl was 15 or 16 when she met her fate in a cave, which at that time was dry, researchers said. She may have been looking for water when she tumbled into the chamber some 12,000 or 13,000 years ago, said study author James Chatters. Her pelvis was broken, suggesting she had fallen a long distance, he said.
The analysis of her remains, reported in the journal Science by researchers from the United States, Canada, Mexico and Denmark, addresses a puzzle about the settling of the Americas.
Where did they come from? Most scientists say the first Americans came from Siberian ancestors who lived on an ancient strip of land, now submerged, that connected Asia to Alaska across the Bering Strait. They are thought to have entered the Americas sometime after 17,000 years ago from that land mass, called Beringia. And genetic evidence indicates that today’s native peoples of the Americas are related to these pioneers.
Naia provides a crucial link. DNA recovered from a tooth contains similar material found in today’s native peoples, especially those in Chile and Argentina. The genetic signature is thought to have arisen among people living in Beringia, researchers said.
That suggests that the early Americans and contemporary native populations both came from the same ancestral roots in Beringia — not different places, the researchers concluded. The anatomical differences apparently reflect evolution over time in Beringia or the Americas, they said.
Journal Science: http://www.sciencemag.org
Reported by Malcom Ritter of the Associated Press