Taiwan DNA discovery sinks Kon-Tiki theory
IAN JOHNSTON
SCIENCE CORRESPONDENT
SCIENTISTS have discovered the mythical homeland of the Polynesians was Taiwan and not, as Norwegian explorer Thor Heyerdahl once famously claimed, South America.
Heyerdahl won international acclaim when he showed that prehistoric sailors could have crossed the Pacific in primitive rafts by making the journey himself on a balsa-wood raft called the Kon-Tiki in 1947.
But while he proved there were trading links between ancient South America and Polynesia, it now appears that the real "Hawaiki" - the Polynesians' original home according to their own myths - is actually Taiwan.
A new DNA study, which was published in the journal PLoS Biology yesterday, found the indigenous population of Taiwan were genetically similar to Polynesians.
The report, by scientists at the Transfusion Medicine Laboratory in Taiwan and Estonia's Biocentre, said: "Analysis of DNA sequences in this study reveals the presence of a motif of three mutations ... [which are] shared among aboriginal Taiwanese, Melanesians and Polynesians. No mainland East Asian population has yet been found to carry lineages derived from these three [DNA] positions.
"This suggests that the motif may have evolved in populations living in or near Taiwan at the end of the late Pleistocene period [more than 10,000 years ago]. The time element ... requires that we adopt a model according to which the origin of Austronesian [including the Polynesian] migration can be traced back to Taiwan."
Heyerdahl first came up with his theory about the origins of Polynesians when he lived on the island of Fatu Hiva in the 1930s and noticed similarities between local plant life and that of South America.
The direction of winds and currents led him to the belief that the Polynesians had travelled from the east and not the north-west. The idea was rubbished by scientists who did not believe prehistoric peoples could have crossed the Pacific.
So, in April 1947, Heyerdahl and five crewmates set out in the Kon-Tiki from Peru on an epic journey that took them 4,300 miles in 101 days to the island of Raroia.
Dr Ingjerd Hoem, head of research at the Kon-Tiki Museum in Oslo, told The Scotsman that her opinion was that Polynesians originated from south-east Asia.
However, she said Heyerdahl, who died in 2002 aged 87, did discover that there had been contact across the Pacific. "They have found evidence of contact in plants like yams and a kind of cotton which were brought from South America," she said.
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From: Stephen Oppenheimer
Date: Fri Jul 1, 2005 8:49 am
Subject: Re: [@ustronesian network] Archaic Mitochondrial Lineages Persist in Austronesian-Speaking Formosans stephen.oppenheimer@...
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Had seen this one before. Very interesting indeed.
Note, the B4a1a node is not the Polynesian motif although it is ancestral to B4a1a1 (which is not found in Taiwan). B4a1a1 is ancestral to the Polynesian motif (which is still not found either in Taiwan or the Philippines). The Polynesian motif is mainly found east of the Wallace Line and dates in this analysis to 9,100 (S.E . 2,700) years ( I previously estimated c. 10K in Melanesia). Although this new sequence info raises the Taiwan question again, a) it pulls Taiwan closer to SE Asia and away from Mainland Asia, b) a Philippines or other ISEA origin for B4a1a is not excluded - and c) the dates appear far too early for the Express train. If the genetic time depth is relevant to linguistic splits (which it need not be), then the latter need to be reviewed as does the relevance of the ETTP and the red-slipped pottery horizon.
p.manansala@sbcglobal.net wrote:
> PLoS Biol. 2005 Jul 5;3(8):e247
>
> Traces of Archaic Mitochondrial Lineages Persist in Austronesian-Speaking Formosan Populations.
>
> Trejaut JA, Kivisild T, Loo JH, Lee CL, He CL, Hsu CJ, Li ZY, Lin M.
>
> Transfusion Medicine Laboratory, Mackay Memorial Hospital, Taipei, Taiwan.
>
> Genetic affinities between aboriginal Taiwanese and populations from Oceania and Southeast Asia have previously been explored through analyses of mitochondrial DNA (mtDNA), Y chromosomal DNA, and human leukocyte antigen loci. Recent genetic studies have supported the "slow boat" and "entangled bank" models according to which the Polynesian migration can be seen as an expansion from Melanesia without any major direct genetic thread leading back to its initiation from Taiwan. We assessed mtDNA variation in 640 individuals from nine tribes of the central mountain ranges and east coast regions of Taiwan. In contrast to the Han populations, the tribes showed a low frequency of haplogroups D4 and G, and an absence of haplogroups A, C, Z, M9, and M10. Also, more than 85% of the maternal lineages were nested within haplogroups B4, B5a, F1a, F3b, E, and M7. Although indicating a common origin of the populations of insular Southeast Asia and Oceania, most mtDNA lineages in Taiw! anese aboriginal populations are grouped separately from those found in China and the Taiwan general (Han) population, suggesting a prevalence in the Taiwanese aboriginal gene pool of its initial late Pleistocene settlers. Interestingly, from complete mtDNA sequencing information, most B4a lineages were associated with three coding region substitutions, defining a new subclade, B4a1a, that endorses the origin of Polynesian migration from Taiwan. Coalescence times of B4a1a were 13.2 +/- 3.8 thousand years (or 9.3 +/- 2.5 thousand years in Papuans and Polynesians). Considering the lack of a common specific Y chromosomal element shared by the Taiwanese aboriginals and Polynesians, the mtDNA evidence provided here is also consistent with the suggestion that the proto-Oceanic societies would have been mainly matrilocal.
>
> Regards,
> Paul Kekai Manansala
> http://sambali.blogspot.com/
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