Traci Watson

Special for USA TODAY

Findings are based on DNA taken from child buried more than 12%2C000 years ago

Research shows the boy%27s predecessors were ancestors of many Native Americans

Other researchers think the evidence is not definitive

Scientists have analyzed the DNA of a little boy buried in Montana more than 12,000 years ago, shedding light on the contentious subject of who peopled the New World.

The results confirm that Native Americans can trace their heritage to the earliest people to firmly establish themselves in the New World. Some scholars have suggested that later migrants who displaced the original settlers are the source of today's native people.

The data imply "that Native Americans are descended from the first people that populated at the least the Lower 48 states … and all of South America," study author Eske Willerslev, an evolutionary geneticist at the University of Copenhagen, said in an interview. "I must say, I didn't expect this result."

Not everyone was surprised.

"This discovery basically confirms what (Native American) tribes never doubted — that we have been here since time immemorial," another study author, Shane Doyle, a professor of Native American studies at Montana State University and a member of the Crow tribe, told reporters Tuesday.

The new insights were born of tragedy. About 12,600 years ago, a boy aged 1 to 1½ was buried with care in what is now central Montana. His body was covered with red-ocher pigment and consigned to the earth along with a cache of 125 tools and other objects, including heirlooms made of rare and valuable elk antler. The boy's cause of death is unknown. His burial, discovered by accident in 1968, is the oldest in North America.

The grave's distinctive spear points and other items show the boy belonged to the Clovis people, who hunted mastodon, mammoth and other big game starting roughly 13,000 years ago. The Clovis people flourished across the modern-day United States and northern Mexico, but the grave site of the "Anzick Child," named for the owners of the land where he was found, is the only known Clovis burial.

When researchers analyzed the Anzick child's DNA and compared it to the genomes of living Native Americans, they found that the boy's family members were the ancestors of multiple Central and South American groups, such as the Maya of Central America and the Karitiana people of Brazil. Willerslev estimates that roughly 80% of Native Americans are descended from the Anzick group, contradicting claims by other scholars that the Clovis people didn't leave much of a genetic legacy.

"The Anzick family is directly ancestral to so many people in the Americas … almost like a missing link, if you will," Willerslev said Tuesday. "That's astonishing."

The results overturn the idea that migrants who colonized the Americas after the Clovis people are the true ancestors to Native Americans. And the discovery "puts the final nail in the coffin" for the idea that the ancestors of Native Americans may have crossed to the New World from Europe, says study author Ripan Malhi of the University of Illinois at Urbana-Champaign.

With the genetic data, the researchers can construct a rough narrative of the peopling of the New World. From Siberia, ancient people gradually crossed a now-vanished land bridge to Alaska. Some drifted south, giving rise to the Clovis people and colonizing the United States and Central and South America. Others stayed in the north and founded the lineage leading to the modern-day Cree and Athabascan peoples of northern North America. The study is published in this week's Nature.

"It's a very important paper and provides very important data," says human geneticist Antonio Torroni of Italy's University of Pavia, who was not involved in the research. But "it's not the end of the story." He and others are cautious about the new study's argument that the Clovis people are the forerunners of many of today's Native Americans.

"It's not an unreasonable hypothesis," says University of Utah anthropological geneticist Dennis O'Rourke. "I wouldn't view it yet as a confirmed bit of history." He says that analyzing more Clovis genomes would clarify the relationship. Study author Michael Waters of Texas A&M University responds that the Anzick child's DNA shows unequivocally that he is related to the peoples of Central and South America.

The debate will continue, but the researchers are drawing praise for reaching out to Native Americans, who have long been wary of scientists seeking to study remains from the past. Willeslev and Doyle visited many tribal representatives living near the burial site and were in contact with others. At the tribes' request, this spring or early summer, the Anzick child will be reburied in the same spot where he was laid to rest more than 12 millennia ago.