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Skulls
and other human remains from P.W. Lund's Collection from Lagoa
Santa, Brazil. Kept in the Natural History Museum of Denmark.
Credit: Natural History Museum of Denmark
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A legal battle over a
10,600-year-old ancient skeleton called the 'Spirit Cave
Mummy' has ended after advanced DNA sequencing found it was
related to a Native American tribe.
The revelation has been
published in Science today as part of a wide-ranging international
study that genetically analyzed the DNA of a series of famous and
controversial ancient remains across North and South America including
Spirit Cave, the Lovelock skeletons, the Lagoa Santa remains, an
Inca mummy, and the oldest remains in Chilean Patagonia. The study
also looked at the second oldest human remains from Trail Creek
Cave in Alaska a 9,000-year-old milk tooth from a young girl.
Scientists sequenced
15 ancient genomes spanning from Alaska to Patagonia and were able
to track the movements of the first humans as they spread across
the Americas at "astonishing" speed during the Ice Age, and also
how they interacted with each other in the following millennia.
The team of academics
not only discovered that the Spirit Cave remains the world's
oldest natural mummy was a Native American but they were
able to dismiss a longstanding theory that a group called Paleoamericans
existed in North America before Native Americans.
The ground-breaking research
also discovered clues of a puzzling Australasian genetic signal
in the 10,400-year-old Lagoa Santa remains from Brazil revealing
a previously unknown group of early South Americans but the
Australasian link left no genetic trace in North America. It was
described by one of the scientists as 'extraordinary evidence of
an extraordinary chapter in human history'.
Professor Eske Willeslev,
who holds positions both at St John's College, University of Cambridge,
and the University of Copenhagen, and led the study, said: Spirit
Cave and Lagoa Santa were very controversial because they were identified
as so-called 'Paleoamericans' based on craniometry"
Spirit
Cave and Lagoa Santa were very controversial because they were
identified as so-called 'Paleoamericans' based on craniometry |
it was determined
that the shape of their skulls was different to current day Native
Americans. Our study proves that Spirit Cave and Lagoa Santa were
actually genetically closer to contemporary Native Americans than
to any other ancient or contemporary group sequenced to date."
The Lagoa Santa remains
were retrieved by Danish explorer Peter W. Lund in the 19th century
and his work led to this 'Paleoamerican hypothesis' based on cranial
morphology that theorized the famous group of skeletons could not
be Native Americans. But this new study disproves that theory and
the findings were launched under embargo by Professor Willeslev
with representatives from the Brazilian National Museum in Rio on
Tuesday, November 6, 2018.
He added: "Looking at
the bumps and shapes of a head does not help you understand the
true genetic ancestry of a population we have proved that
you can have people who look very different but are closely related."
The scientific and cultural
significance of the Spirit Cave remains, which were found in 1940
in a small rocky alcove in the Great Basin Desert, was not properly
understood for 50 years. The preserved remains of the man in his
forties were initially believed to be between 1,500 and 2000 years
old but during the 1990s new textile and hair testing dated the
skeleton at 10,600 years old.
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A
drawing of the remains of the 10,600-year-old "Spirit
Cave Mummy" found in a rock shelter near Fallon, Nevada,
in 1940.
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The Fallon Paiute-Shoshone
Tribe, a group of Native Americans based in Nevada near Spirit Cave,
claimed cultural affiliation with the skeleton and requested immediate
repatriation of the remains under the Native American Graves Protection
and Repatriation Act.
The request was refused
because the ancestry was disputed, the tribe sued the federal government
and the lawsuit pitted tribal leaders against anthropologists, who
argued the remains provided invaluable insights into North America's
earliest inhabitants and should continue to be displayed in a museum.
The deadlock continued
for 20 years until the tribe agreed that Professor Willeslev could
carry out genome sequencing on DNA extracted from the Spirit Cave
for the first time.
Professor Willeslev said:
"I assured the tribe that my group would not do the DNA testing
unless they gave permission and it was agreed that if Spirit Cave
was genetically a Native American the mummy would be repatriated
to the tribe."
The team painstakingly
extracted DNA from the Petrus bone from the inside of the skull
proving that the skeleton was an ancestor of present-day Native
Americans. Spirit Cave was returned to the tribe in 2016 and there
was a private reburial ceremony earlier this year that Professor
Willeslev attended and details have just been released.
The geneticist explained:
"What became very clear to me was that this was a deeply emotional
and deeply cultural event. The tribe has real feelings for Spirit
Cave, which as a European it can be hard to understand but for us,
it would very much be like burying our mother, father, sister or
brother.
"We can all imagine what
it would be like if our father or mother was put in an exhibition
and they had that same feeling for Spirit Cave. It has been a privilege
to work with them."
The tribe was kept informed
throughout the two-year project and two members visited the lab
in Copenhagen to meet the scientists and they were present when
all of the DNA sampling was taken.
A statement from the
Fallon Paiute-Shoshone Tribe, said: "The Tribe has had a lot of
experience with members of the scientific community, mostly negative.
However, there are a handful of scientists that seemed to understand
the Tribe's perspective and Eske Willerslev was one of them.
"He took the time to
acquaint himself with the Tribe, kept us well-informed of the process,
and was available to answer our questions. His new study confirms
what we have always known from our oral tradition and other evidence
that the man taken from his final resting place in Spirit
Cave is our Native American ancestor."
The genome of the Spirit
Cave skeleton has wider significance because it not only settled
the legal and cultural dispute between the tribe and the Government,
it also helped reveal how ancient humans moved and settled across
the Americas. The scientists were able to track the movement of
populations from Alaska to as far south as Patagonia. They often
separated from each other and took their chances travelling in small
pockets of isolated groups.
Dr. David Meltzer, from
the Department of Anthropology, Southern Methodist University, Dallas,
said: "A striking thing about the analysis of Spirit Cave and Lagoa
Santa is their close genetic similarity which implies their ancestral
population traveled through the continent at astonishing speed.
That's something we've suspected due to the archaeological findings,
but it's fascinating to have it confirmed by the genetics. These
findings imply that the first peoples were highly skilled at moving
rapidly across an utterly unfamiliar and empty landscape. They had
a whole continent to themselves and they were traveling great distances
at breath-taking speed."
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A
map showing the possible early migration routes into North
and South America as posited by the Cell study.
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The study also revealed
surprising traces of Australasian ancestry in ancient South American
Native Americans but no Australasian genetic link was found in North
American Native Americans.
Dr Victor Moreno-Mayar,
from the Centre for GeoGenetics, University of Copenhagen and first
author of the study, said: "We discovered the Australasian signal
was absent in Native Americans prior to the Spirit Cave and Lagoa
Santa population split which means groups carrying this genetic
signal were either already present in South America when Native
Americans reached the region, or Australasian groups arrived later.
That this signal has not been previously documented in North America
implies that an earlier group possessing it had disappeared or a
later arriving group passed through North America without leaving
any genetic trace."
Dr. Peter de Barros Damgaard,
from the Centre for GeoGenetics, University of Copenhagen, explained
why scientists remain puzzled but optimistic about the Australasian
ancestry signal in South America. He explained: "If we assume that
the migratory route that brought this Australasian ancestry to South
America went through North America, either the carriers of the genetic
signal came in as a structured population and went straight to South
America where they later mixed with new incoming groups, or they
entered later. At the moment we cannot resolve which of these might
be correct, leaving us facing extraordinary evidence of an extraordinary
chapter in human history! But we will solve this puzzle."
The population history
during the millennia that followed initial settlement was far more
complex than previously thought. The peopling of the Americas had
been simplified as a series of north to south population splits
with little to no interaction between groups after their establishment.
The new genomic analysis
presented in the study has shown that around 8,000 years ago, Native
Americans were on the move again, but this time from Mesoamerica
into both North and South America.
Researchers found traces
of this movement in the genomes of all present-day indigenous populations
in South America for which genomic data is available to date.
Dr. Moreno-Mayar added:
"The older genomes in our study not only taught us about the first
inhabitants in South America but also served as a baseline for identifying
a second stream of genetic ancestry, which arrived from Mesoamerica
in recent millennia and that is not evident from the archaeological
record. These Mesoamerican peoples mixed with the descendants of
the earliest South Americans and gave rise to most contemporary
groups in the region."
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