This pretty well
nails it. We have been posting on this
likelihood for a long time wondering just when the DNA work would lock it
down. This is it.
Siberian stock
was largely congruent with European stock and its natural extension into the
Americas. That likely held true for the
several thousands of years prior to the Pleistocene Nonconformity of 12900
BP. After the Ice Age life way ended so
abruptly, adjacent populations moved northward into these new territories and
these were mostly East Asian associated with the types out of the highlands of
the Himalayas.
They likely made
the crossings by sea along the coasts.
There will be
plenty more DNA surprises but we now have blocked out the shape of the
migrations. This includes our recent
report on DNA in Mexico from 24000 BP that is clearly European.
New evidence
shows Native Americans' origins are older than previously thought
The new evidence shows that pre-Columbian American
Indians had European ancestors.
WEDNESDAY, NOVEMBER 20, 2013
A genetic analysis of human remains from 24,000
years ago has given scientists an important bit of evidence in resolving
remaining questions over the origins of pre-Columbian Americans. A genome
sequence of the ancient Siberian by a team led by the Center
forGeoGenetics of the Natural History Museum at the University of
Copenhagen shows signatures that relate to peoples of western Eurasia (in other
words: Europe) and also to modern Native Americans. The breakthrough
reveals much about the genetic composition of human beings living ages ago on
the Eurasia landmass. It is believed, as a result of the study, that
pre-Columbian or First Americans have ancestors who were a mixture of at least
two populations. One of these is related to modern East Asians such the Koreans
and Japanese, and the other to modern people of western Eurasia. This may
explain why Native Americans show mitochondrial lineage X in their genetic make
up.
"The result came as a complete surprise to us.
Who would have thought that present-day Native Americans, who we learned in
school derive from East Asians, share recent evolutionary history with
contemporary western Eurasians?”
said Eske Willerslev ofGeoGenetics. Of the study,
Kelly Graf from Texas A&M University said "Our findings are
significant at two levels. First, it shows that Upper Paleolithic Siberians
came from a cosmopolitan population of early modern humans that spread out of
Africa to Europe and Central and South Asia. Second, Paleoindian skeletons
with phenotypic traits atypical of modern-day Native Americans can be explained
as having a direct historical connection to Upper Paleolithic Siberia."
It was at the Russia’s Hermitage Museum in St.
Petersburg that researched conducted samples in 2009 of the remains of a
teenaged individual (MA-1) from Mal’ta – a site in the south central
region of Siberia where artifacts from the Upper Palaeolithic age
have been found. This individual has been dated to about 24,000 years ago. “Representing
the oldest anatomically modern human genome reported thus far, the MA-1
individual has provided us with a unique window into the genetic landscape of
Siberia some 24,000 years ago", said Dr. Maanasa Raghavan.
According to Raghavan, who works at GeoGenetics, the sampled
individual shows hardly any genetic affinity to the people now living in his
place of origin: southern Siberia.
The genetic evidence indicates that MA-1 is actually
related to modern western Eurasians. The subject’s genome provides evidence,
therefore, that peoples related to modern western Eurasians ranged much wider
range than previously thought.
However, the MA-1 genome, most importantly, shows
its relationship to Native Americans living today. Interestingly, while MA-1 is
closely related to Native Americans living today, there is little affinity to
East Asians who are believed to be close relatives to Native Americans.
The team led by Ragavan has concluded that
the genetic affinity between MA-1 and Native Americans has an admixture of
ancestry evidenced by MA-1, thus explaining between 14-38% of modern Native
Americans, with the remainder of the ancestry being derived from East Asians.
The study holds that two different Eurasian peoples contributed to the gene
pool of the First Americans. One of these is to East Asians of the present day,
while the other stems from an Upper Palaeolithic population from
Siberia that is related to modern western Eurasians.
The team also offered results from examining a
second south-central Siberian from the Afontova Gora-2 site.
This individual lived approximately 17,000 years ago, which was at a time
that followed the so-called Last Glacial Maximum (ca. 26,000-19,000 years ago),
when glaciers reached their maximum extent in Eurasia and North Ameirca.
The study showed that this second individual showed genomic signatures
that are similar to MA-1, and thus has close affinity to western Eurasians and
Native Americans living today but none to modern East Asians. This means there
was a continuity of genetic affinity throughout the glacial age and must be
taken into consideration when researchers and anthropologists look into the
issue of human migration into early America approximately 15,000 years ago.
In summing up the findings,
Dr. Pontus Skoglund from Uppsala University explained,
"Most scientists have believed that Native American lineages go back
about 14,000 years ago, when the first people crossed Beringia into
the New World. Our results provide direct evidence that some of the ancestry
that characterizes Native Americans is at least 10,000 years older than that,
and was already present in Siberia before the last Ice Age."
Ancient, modern
DNA tell story of first humans in the Americas
University of Illinois anthropology professor Ripan
Malhi looks to DNA to tell the story of how ancient humans first came to the
Americas and what happened to them once they were here.
He will share
some of his findings at the meeting, "Ancient DNA: The First Three
Decades," at The Royal Society in London on Nov. 18 and 19.
Malhi, an affiliate of the Institute for Genomic Biology at Illinois, will describe his collaborative approach, which includes working with present-day Native Americans on studies of their genetic history.
He and a group of collaborators from the Tsimshian Nation on the northwest coast of British Columbia, for example, recently found a direct ancestral link between ancient human remains in the Prince Rupert Island area and the native peoples living in the region today. That study looked at changes in the mitochondrial genome, which children inherit only from their mothers.
Other studies from Malhi's lab analyze changes in the Y chromosome or the protein-coding regions of the genome.
"The best opportunity to infer the evolutionary history of Native Americans and to assess the effects of European colonization is to analyze genomes of ancient Native Americans and those of their living descendants," Malhi said.
"I think what makes my lab unique is that we focus not only on the initial peopling of the Americas but also what happened after the initial peopling. How did these groups move to new environments and adapt to their local settings over 15,000 years?"
While continuing his work in British Columbia, Malhi also is setting up study sites in California, Guatemala, Mexico and Illinois.
"What's interesting about the northwest coast and California is that these communities were complex hunter-gatherer societies, whereas in Mexico and Guatemala, it's more communities that transitioned to farming and then experienced the effects of European colonization," he said.
Genomic studies can fill in the blanks on studies that seek to tell the story of life in the Americas before and after European colonization, Malhi said. Researchers may draw the wrong conclusions about human history when looking only at artifacts and language, he said.
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