Evidence that Polynesians visited the Americas has been
intriguing, if controversial, but new genetic studies of Rapa Nui (Easter
Island) natives seem to confirm it.
Results of thorough genetic studies on 27 Rapa Nui natives reveal
the presence of South American DNA that showed up 19 to 23 generations ago.
That takes it back to 1280 to 1495, before Europeans were in the Pacific.
There is European DNA there, too, but it showed up much
later, in the 1800s. Rapa Nui wasn’t discovered by Europeans until the Dutch
voyager Jacob Roggeveen visited on Easter of 1722.
This new genetic work adds to other evidence: The presence
of American sweet potatoes and possibly American bottle gourds throughout the
Pacific, and the presence of Polynesian chicken DNA at El Arenal in Chile.
RaisingIslands covered the Polynesian chicken research here.
The new genetic evidence, published in the 23 October issueof Current Biology, seems to lock up once and for all the mystery: Is it
possible that Polynesians, having discovered every single habitable island in
the tropical and subtropical Pacific, could have missed the American continent?
The authors of the paper, entitled Genome-wide Ancestry Patterns in Rapanui Suggest Pre-European Admixture
with Native Americans, write:
“We generated genome-wide data for 27 Rapanui. We found a
mostly Polynesian ancestry among Rapanui and detected genome-wide patterns
consistent with Native American and European admixture. By considering the
distribution of local ancestry tracts of eight unrelated Rapanui, we found
statistical support for Native American admixture dating to AD 1280–1495 and
European admixture dating to AD 1850–1895,” the authors wrote.
“These genetic results can be explained by one or more
pre-European trans-Pacific contacts,” they said.
The paper was written by a dozen scholars: J. Víctor
Moreno-Mayar, Simon Rasmussen, Andaine Seguin-Orlando, Morten Rasmussen, Mason
Liang, Siri Tennebø Flåm, Benedicte Alexandra Lie, Gregor Duncan Gilfillan,
Rasmus Nielsen, Erik Thorsby, Eske Willerslev, and Anna-Sapfo Malaspinas.
It is theoretically possible that the American genes got
there from South American sailors making the voyage to Rapa Nui, but since
Polynesians have a famous voyaging and navigation culture and South Americans
did not, it seems unlikely.
This sets up interesting speculations.
Polynesians are believed to have reached Rapa Nui about 1200 AD. Was it members
of that same initial voyaging group that went on to visit the South American
coast and then return? Or did Polynesian navigation continue between the Eastern Pacific
islands and South America for generations after the initial Rapa Nui visit.
There’s a lot of stuff happening in the first few centuries
of the millennium in Eastern Polynesia. Sweet potato showed up in the Pacific around 1000 AD. Rapa
Nui folks arrived at an uninhabited Rapa Nui about 1200. South American genes
got into the Rapa Nui gene pool between 1280 and 1495. The El Arenal chicken bones were dated at 1321
to 1407.
It was all going on during the period when Polynesian
cultures were known to be actively voyaging across the Pacific. It may be a
stretch, but it seems that this new genetic data suggests not a single
accidental voyage to the Americas, but a series of voyages, in which at a
minimum:
-- Sweet
potatoes were collected in the Americas and delivered into the Pacific.
-- Polynesian
moa (chickens) were delivered from the Islands to the American Coast.
-- And there
was some genetic mixing. Did a Polynesian sailor bring home a mate, or did
Polynesians stay long enough to have children and bring them home, or did a
couple of venturesome South American natives join the Polynesian canoe for the
trip to Rapa Nui?
Here is Science Daily’s story on the paper.
As a side note, the evidence is also another piece of
evidence for the quality of Polynesian navigation. Unlike many of the islands in
the Pacific, Rapa Nui is a loner. It is small, and not part of a chain of
islands like Hawaii, Tahiti, the Marquesas, Samoa and so forth. Those would be
easier to find since they’re a much bigger target--you just have to find the archipelago.
But Polynesian navigators appear to have found tiny Rapa Nui
repeatedly, and from both the east and the west. That is a prodigious
navigational feat.
© Jan TenBruggencate 2014
Citation: J. Víctor Moreno-Mayar, Simon Rasmussen, Andaine
Seguin-Orlando, Morten Rasmussen, Mason Liang, Siri Tennebø Flåm, Benedicte
Alexandra Lie, Gregor Duncan Gilfillan, Rasmus Nielsen, Erik Thorsby, Eske
Willerslev, Anna-Sapfo Malaspinas. Genome-wide Ancestry Patterns in Rapanui
Suggest Pre-European Admixture with Native Americans. Current Biology, 2014
DOI: 10.1016/j.cub.2014.09.057
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