We
have posted on this in the past but the key take home here is that a
ship load or perhaps even an expedition similar to Polynesian
expeditions took off from Indonesia and went with the winds until
they fetched up on Madagascar. What is noteworthy is just how small
a founding group can be. It is thus easy to backtrack for the far
greater occupations of continents that also likely were smallish one
way trips.
The
real problem is just how recent that event was. Sea beds have been
much lower and many more islands could have acted as stepping stones.
I find it difficult to believe that a prior population did not
exist and live there. It may even have been wiped out or simply have
not succumbed to intermarriage until much later when Africans had
arrived and larger settled populations drew down against subsistence
hunters.
It
will take careful archeology to show any of this and I suspect no one
is looking too hard yet.
A.D. 830: A storm
sends an Indonesian trading ship drastically off course. Months
later, dozens of ragged survivors make landfall on an island off the
southeast coast of Africa, more than 3,000 miles from home.
Today,Murray
Cox, a computational biologist at New Zealand’s
Massey University, says a scenario like this may describe the murky
origins of the first permanent settlements on Madagascar, home to
about 22 million people today.
Genetic and linguistic
studies suggest the island’s native Malagasy people
are mainly of Indonesian descent. The idea of early Indonesians
traveling 3,000 miles to the island intrigued Cox. “It’s a
surprisingly long distance to come,” he says. So he used computer
modeling to parse the clues, running through 40 million settlement
simulations. Cox soon pinpointed one that would explain the DNA
patterns evident in Madagascar today.
Surprisingly, the
current population descends primarily from
just 30 or so Indonesian women who arrived 12 centuries ago [pdf].
His conclusion is supported by prior findings that
about 30 percent of Malagasy have the same mitochondrial DNA, which
is passed from mother to child—far less diversity than in typical
human populations, which share less than 2 percent. “This suggests
rapid, recent growth from a very small founder population,” Cox
says.
It is unclear how
Madagascar’s founding mothers (and the fathers who must have been
with them) arrived. Cox proposes seafaring merchants thrown off
course, or refugees fleeing political strife; the latter could
explain why women, usually not found on trade ships, were on board.
Now, Cox plans to explore whether small founding groups are
characteristic of other early island settlements, including Hawaii.
“There may be general rules for settling islands,” he says.
From wired
Madagascar's first residents
could have arrived with a shipwreck
By Ian
Steadman
The Malagasy people
of Madagascar are genetically fascinating. Despite the island's
location just off the coast of Africa, it was only settled relatively
recently -- a mere thousand years ago, according to most estimates.
Even more surprising is that many of the Malagasy are of Polynesian
descent, with the same linguistic and cultural characteristics also
found in a small region of southern Borneo, over 7,000km away.
The exact
circumstances of how those settlers arrived on the other side of the
Indian Ocean has until now been unclear, but surprising analysis of
settlement patterns seems to suggest that Malagasy with Polynesian
heritage can trace their lineage back to one of only 30 women, who
landed on the island roughly 1,200 years ago. According to molecular
bioscientist Murray
Cox of Massey University in New Zealand,
this means that the settlement of Madagascar might have been the
result of a one-off event like a shipwreck rather than any deliberate
migration.
Discover
Magazine reports that the study, published
in the Proceedings
of the Royal Society, used previous research
which had found that 30 percent of Malagasy people shared the same
maternal mitochondria. A diverse population of humans would normally
share only two percent, by comparison. Cox and his team ran 40
million different simulations of settlement events to see which was
the most likely to have given rise to the current genetic patterns on
the island, with the most likely result being a one-off settlement of
30 women landing 1,200 years ago. This fits with the evidence that
Madagascar's current population of almost 22 million grew rapidly
from a small base population over a short period of time.
The implications of
such a small base population are intriguing, because it does not
suggest any kind of planned mass migration. It could be that
Madagascar was settled by accident by a shipwreck -- Cox proposes
some kind of refugee ship rather than a merchant vessel, which would
be less likely to carry women.
Madagascar was settled
by people from what is now Indonesia and, later, by Africans from the
eastern kingdoms of the continent -- but the two groups came into
conflict as they established towns and cities. The Marina people of
the central highlands (of mostly Polynesian heritage) eventually came
to dominate the entire island -- including the coastal peoples of
African descent -- by the 1800s, but their dominance was brought to
an end when the whole of Madagascar was subjugated by the French in
1897.
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