1.20.2008

[轉載] Pacific Islanders' Ancestry Emerges in Genetic Study

This article is provided by our new friend, Lily Hsueh.
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I want to share the following New York Times article that reports on research that shows/ reinforces previous academic findings of a genetic link between Polynesians and Micronesians and Taiwan Aborigines. It quotes a biological anthropologist from Temple University who led an international team of scholars to make this most recent genetic analysis. It also quotes an anthropologist on Pacific cultures from U.C. Berkeley who affirms this recent genetic research as providing "overwhelming biological evidence for a clear population movement out of Southeast Asia and Taiwan to Polynesia."
~Lily Hsueh
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NYT January 18, 2008
Pacific Islanders' Ancestry Emerges in Genetic Study
By JOHN NOBLE WILFORD

The ancestral relationships of people living in the widely scattered
islands of the Pacific Ocean, long a puzzle to anthropologists, may
have been solved by a new genetic study, researchers reported
Thursday.

In an analysis of the DNA of 1,000 individuals from 41 Pacific
populations, an international team of scientists found strong evidence
showing that Polynesians and Micronesians in the central and eastern
islands had almost no genetic relationship to Melanesians, in the
western islands like Papua New Guinea and the Bismarck and Solomons
archipelagos.

The researchers also concluded that the genetic data showed that the
Polynesians and Micronesians were most closely related to Taiwan
Aborigines and East Asians. They said this supported the view that
these migrating seafarers originated in Taiwan and coastal China at
least 3,500 years ago.

The findings were described in the online journal Public Library of
Science Genetics (www.plosgenetics.org) by researchers led by Jonathan
S. Friedlaender, professor emeritus of biological anthropology at
Temple University. He was assisted in the data analysis by his wife,
Françoise R. Friedlaender, an independent researcher. Other
participants included scientists in the islands and at the Marshfield
Clinic Research Foundation in Marshfield, Wis.

"Our analysis," the scientists wrote, "indicates the ancestors of
Polynesians moved through Melanesia relatively rapidly and only
intermixed to a very modest degree with the indigenous populations
there."

Dr. Friedlaender of Temple said in an interview that the evidence was
"substantial" and "solves a number of issues about the migration and
settlement of Pacific people."

In particular, he and other anthropologists not involved in the study
said, the genetic research supported the "fast train" hypothesis.
Increasing archaeological and linguistic evidence in recent years has
suggested that ancestors of Micronesians and Polynesians had moved
through Indonesia and Melanesia without having any significant contact
there, culturally or genetically.

An alternative argument, the "slow boat" hypothesis, which had some
support from male Y chromosome studies, raised the possibility that
Polynesians were primarily Melanesians who had ventured on in their
outrigger canoes. And a few anthropologists despaired of ever solving
the mystery. Theirs was the "entangled bank" hypothesis.

The new genetic research, said Patrick V. Kirch, an anthropologist at
the University of California, Berkeley, who is an authority on Pacific
cultures, was "overwhelming biological evidence for a clear population
movement out of Southeast Asia and Taiwan to Polynesia."

Dr. Kirch, who did not participate in the genetic study, said that it
reinforced research showing that Polynesian speech patterns were
unrelated to Melanesian languages, suggesting — along with discoveries
of the distinctive Lapita pottery across the Pacific — links to Taiwan
and China, not Melanesia. "The combination of evidence shows we really
can read this history," he said.

As Dr. Friedlaender said, "If it wasn't exactly an express train, it
was pretty fast, and very few passengers climbed aboard or got off
along the way."

In the research, scientists examined more than 800 genetic markers
known to be useful in distinguishing the ancestry of people. These
involved mitochondrial DNA, passed down through females, and the Y
chromosomes in males. Previous investigations along these lines had
been conducted on a much smaller scale, Dr. Friedlaender said.

The new test results were repeatedly analyzed with a software program
recently developed to classify genetic similarities and variations
among different populations.

Primary support for the study was provided by the National Science
Foundation, the Wenner-Gren Foundation of Anthropological Research,
the National Geographic Society and the National Institutes of Health.

Further research to confirm the history of the Pacific diaspora, Dr.
Friedlaender said, would require an expansion of genetic tests among
people in the Philippines and Indonesia, regions that the migrants
presumably passed through after leaving Taiwan more than 3,500 years
ago, ultimately reaching as far as Hawaii and Easter Island. The
Melanesians, on the other hand, probably arrived on their islands
about 35,000 years ago, sometime later than the Aborigines reached
Australia.

Years ago, a reporter who visited the Marshall Islands asked an aging
Micronesian chief where his people came from long, long ago. "We have
always been here," he replied. Now, if it matters to them, his
descendants have been given a more scientific answer.

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