The genome of a child who died some 12,600 years ago in Montana – the oldest known human remains from North America – has been sequenced for the first time.
The young boy’s genetic blueprint reveals that the Americas’ first human inhabitants came from Asia, not Europe, laying to rest a long-standing mystery.
Conducted by a consortium of scientists led by the University of Copenhagen and including Drs Andrea Manica, Anders Eriksson and Vera Warmuth at the University of Cambridge, the study is published in Nature.
The child belonged to the Clovis people. They produced beautiful, distinctive stone and bone tools, and are named after the New Mexico town of Clovis where caches of the tools were first found in the 1920s and 30s.
The Clovis culture moved south through the Americas, but where it came from, how it spread and whether modern Native Americans are descendants of the Clovis people has puzzled scientists.
Until now, two conflicting theories existed. One suggests that humans arrived in North America from Siberian parts of Asia through a corridor between the melting ice sheets, and that these people are the ancestors of modern Native Americans.
A second theory – known as the Solutrean – suggests people first travelled to the Americas from Europe via Greenland across the frozen ocean.
According to Dr Manica: “When we look at arrow and spear heads from the parts of Asia where we think Native Americans originated, we find no such technology, nothing that looked anything like a Clovis arrow head.
“On the other hand if we go all the way to Spain and France, we can find some arrow heads that resemble, to a certain extent, what we find in the Clovis culture.”
Solving the mystery depended on finding a well-preserved Clovis skeleton, from which researchers could extract DNA.
They located a skeleton that had been discovered, together with Clovis tools, in 1968 on a Montana farm. It is the only known Clovis burial site, and carbon-14 dating shows the bones are around 12,600 years old, close to the end of the Clovis culture.
“After obtaining permission from the current Native American tribes who live in the area, we were able to take the bones to the lab and extract the DNA. The bones turned out to be so well preserved that we were able to reconstruct the entire genome of that individual,” said Dr Manica.
The child’s DNA revealed that the Clovis people came from Siberia, laying to rest the Solutrean theory.
“When we looked at this genome, it was definitely Asian; there was no sign of any European DNA, so it seems very clear that the people who made those Clovis artefacts were part of the Asian wave that came into the Americas about 15,000 years ago when the ice sheets started melting. Some stopped in North America, and invented the Clovis technology, and others continued all the way down to South America,” he said.
“As well as having a very clear Asian origin, it’s also very closely related to modern Native Americans. So the Clovis mystery is solved: we now know that Clovis were Asians and part of the group of people who colonised the Americas.”
Although the burial site is on private land owned by the Anzick family, the researchers worked closely with nine Native American groups with reservations in the surrounding area. A Crow tribe representative, together with the Anzick family, is working on an intertribal reburial of the bone fragments.
Header Image : Clovis point, 11500-9000 BC, Sevier County, Utah : WikiPedia
Contributing Source : University of Cambridge