WASHINGTON (AP) — The native peoples of the scattered Polynesian islands in the vast eastern Pacific may have migrated there via Southeast Asia and Indonesia, a new study indicates. Previous research had suggested Polynesian origins were in Taiwan or the
WASHINGTON (AP) — The native peoples of the scattered Polynesian islands in
the vast eastern Pacific may have migrated there via Southeast Asia and
Indonesia, a new study indicates.
Previous research had suggested
Polynesian origins were in Taiwan or the southwestern Pacific islands of
Melanesia.
But a new study led by Bing Su of the University of Texas Health
Science Center in Houston fails to support the older theory, suggesting the
South Asian migration route. The findings are being published in Tuesday’s
issue of Proceedings of the National Academy of Science.
The team studied
the Y chromosomes of 551 men from across the Pacific and Southeast Asia,
comparing the distribution of 15 specific genetic markers on those chromosomes.
The Y chromosome is specific to males and is passed from father to
son.
They found that the Taiwanese aboriginal peoples carried a different
set of these markers than either the Polynesians of the eastern Pacific or the
Micronesians of the northwestern Pacific.
Indeed, the study concluded that
“the divergence between the Taiwanese and the Micronesian/Polynesian
populations is twice as great as the divergence of either population group from
Southeast Asians.”
The researchers concluded that the most likely
explanation for their findings is that both the original Taiwanese and the
Polynesians originated in Southeast Asia, but that they dispersed independently
of one another.
The researchers also noted that there has been controversy
over the extent to which the Melanesians of the southwestern Pacific
contributed to the populations of Micronesia, to their north, and Polynesia, to
their east.
They found one marker, H17, common in Melanesians was
completely missing in Polynesians, suggesting the Melanesian contribution was
“very low or negligible.”
They also found no significant European
contribution to Polynesian ancestry.
While the Y chromosome study does not
unequivocally point to a center of origin for the Polynesians, the islands of
Southeast Asia, such as the Indonesian group, emerge as a probable migration
route, the researchers said.
The earlier theory of Polynesian origins,
suggesting dispersal via Taiwan, had been based on studies of mitochondrial
DNA. That is a type of DNA inherited only from the mother.
Some questions
about the earlier studies have been raised in recent years, but the researchers
said the reason for the different findings using the male-only Y chromosome is
unclear. One possibility, they suggested, might have been differences in male
and female migration patterns.
Polynesia is the group of Pacific Islands
east of the International Date Line, including Hawaii, Samoa, Tonga, the
Society Islands and others. Melanesia is generally south of the Equator and
west of the date line, including the islands from the New Guinea to Fiji, the
Solomon Islands and Vanuatu. Micronesia is north of the Equator and west of the
date line, including the Mariana, Marshall and Caroline islands.
