The skeletal remains of a young girl who fell into a subterranean hole inside a Mexican cavern and died almost 13,000 years ago will be recovered, officials say.
DNA retrieved from the nearly-complete skeleton has led scientists to a new understanding of the first people in North America, suggesting they did in fact cross from Asia into Alaska over a land bridge that existed in the last Ice Age to become the ancestors of today's North and South American people.
Mitochondrial DNA in the skeleton matches that found in modern-day Native Americans, researchers say.
The DNA analysis shows the young girl, dubbed Naia after a water nymph in Green mythology, is a direct ancestor of many modern Native Americans, and shows a link to hunter-gatherers who lived in Siberia and crossed the now-submerged land bridge about 17,000 years ago.
After entering North American they slowly spread south as far as southern Mexico and on into South America.
Genetic studies of modern Native Americans suggests they are linked to a population that originated in Asia and was then isolated from other population groups for several thousand years on or near the land bridge that has been dubbed Beringia.
Only part of Naia's remains -- a tooth and a rib fragment, taken for the DNA studies -- have been recovered from the water-filled cave named Hoyo Nego, Spanish for "black hole," partly for safekeeping because unauthorized divers attempting to obtain photographs moved and damaged some of the bones.
"We tried to keep everything in situ," says Maria del Pilar Luna Erreguerena, chief of underwater archaeology at the National Institute of Anthropology and History in Mexico.
Now an effort will be made to recover the entire skeleton for study and eventually display, Luna says.
The chamber where her bones were discovered also contained the remains of Ice Age creatures such as sabre-tooth cats, giant ground sloths and cave bears, suggesting a search for water what would have been a dry environment at the time lured the animals and Naia into the cave and to their deaths.
Although dry at the times, rising sea levels have since flooded the cave system, one of the largest underwater cave systems ever surveyed anywhere in the world.