Friday, October 1, 2010

49,000 years ago migration got out of their canoes and headed uplands.

49,000 years ago migration got out of their canoes and headed uplands.
Two articles.


PNG find prompts human migration rethink
By: Julian Swallow | October-1-2010


49,000-year-old artefacts have been unearthed in PNG, suggesting a
rethink of human migration patterns.


The Ivane Valley in PNG, where 49,000 year-old artefacts have been
uncovered. (Photo: Glenn Summerhayes and Andrew Fairbairn)


ANCIENT ARTEFACTS UNEARTHED IN the highlands of Papua New Guinea
provide some of the earliest evidence of human settlement of Sahul,
the primordial landmass that once joined Papua New Guinea with
Australia.


Charred nut shells from pandanus trees, fragments of animal bone and
the remains of stone axes were found in the remote Ivane Valley of
south-eastern Papua New Guinea - near the famous Kokoda Track - by a
team led by archaeology Professor Glenn Summerhayes from the
University of Otago, New Zealand.


These artefacts, which have been dated to between 49,000 and 44,000
years old, may prompt a rethink of the traditional view that the
prehistoric migration of people throughout the world took place along
the coasts.


"This is among the earliest evidence of human habitation in this part
of the world, or indeed any place outside Africa, India and the Middle
East," Glenn told Australian Geographic. "Many models for the
movements of people argue for a colonisation route along the coast,
arguing that people were pre-adapted to a coastal way of life...Our
evidence shows such a pre-adaptation would have been short lived as
people moved into highland valleys as soon as they got out of their
canoes."


Ivane Valley resident, Paul Lamui, demonstrates how to use rocks to
crack pandanus nuts open - the same method used 49,000 years ago
according to excavation evidence in the Ivane Valley of PNG. (Photo:
Andrew Fairbairn)
"Cold, uncompromising place"


The team's study is published today in the journal Science.


Professor Peter Bellwood, an archaeologist at ANU who was not part of
the team, agrees the wealth of evidence found in the Ivane Valley
"provides the first reliable dates for the earliest habitation of the
PNG Highlands."


Professor Chris Gosden from the University of Oxford - who writes a
related article in the same issue of Science - says its unlikely early
humans would have lived there permanently as it was a "cold, difficult
and uncompromising place to live at any time over the past 50,000
years."


Starch grains from yams recovered in the valley appear to support
this, having most likely been transported there from their natural
habitat in the lower elevations closer to the country's steamy sub-
tropical coast.


Highly mobile


Archaeologist Dr Andrew Fairbairn from the University of Queensland,
who worked with Glenn on the research, says this suggests early humans
lived in small nomadic populations that moved up and down the
mountains of Papua New Guinea in search of food.


"They clearly were very mobile. We assume [they lived in] some form of
egalitarian structure, but it's very difficult to say from the
archaeological remains alone. It was a very cold period in history and
these people were both resourceful and capable to be able to live at
this altitude," he says.


Long isolated by water, Sahul is thought to have been first colonised
via canoe from Southeast Asia sometime after 50,000 years ago. The
subsequent settlement of the Papua New Guinea Highlands was a
forerunner to the great migrations that took place several thousand
years later, when other parts of Sahul were settled, including wet and
semi-arid parts of Australia.


A map of the Ivane Valley in Papua New Guinea at the citation





and


Ancient New Guinea settlers headed for the hills
First human arrivals rapidly adapted to mile-high forests 50,000 years
ago
By Bruce Bower
Web edition : 2:06 pm
font_down font_up Text Size
access
Enlargemagnify
Tree TopplerPeople who reached New Guinea nearly 50,000 years ago
fashioned stone tools dubbed waisted axes, such as this specimen shown
from three angles, that were apparently used to fell trees and clear
patches of forest in a mountain valley.G. Summerhayes


Excavations in Papua New Guinea’s western highlands have turned up the
oldest well-documented evidence of people in Sahul, a land mass that
once joined the island to Australia.


Stone tools and plant remains indicate that, as early as 49,000 years
ago, people lived 2,000 meters, or 1.2 miles, above sea level in Papua
New Guinea’s Ivane Valley, say archaeologist Glenn Summerhayes of the
University of Otago in Dunedin, New Zealand, and his colleagues.


By at least 50,000 years ago, modern humans occupied lowland
rainforests and savannas of southeastern Asia’s land mass known as
Sunda. From there they crossed the open ocean to Sahul, presumably in
seacraft of some kind. Rising sea levels separated Papua New Guinea
from Australia roughly 10,000 years ago.


Many researchers assume that modern humans spread from Africa to Sahul
along the coast and preferred living at low altitudes. That idea gets
drubbed by the new discoveries, Summerhayes says. Shortly after
reaching Sahul’s shores, settlers headed uphill to the Ivane Valley’s
thin air, cold temperatures and harsh habitat, the scientists conclude
in the Oct. 1 Science.


“Early occupation of such adverse environments contributes to a model
in which small numbers of foraging peoples moved around the Sahul
landscape, colonizing new areas and then returning back to where they
had been,” Summerhayes says.
access
Enlargemagnify
GOING UPAfter crossing the sea from southeastern Asia to New Guinea,
people reached the mile-high Ivane Valley between 49,000 and 43,000
years ago, making them the earliest known settlers of a land mass
called Sahul, which at the time included Australia. Science © 2010
AAAS


Despite the challenges at high altitudes, prehistoric people had the
mental savvy to survive, archaeologist Chris Gosden of the University
of Oxford in England writes in a comment published in the same issue
of Science. Crucial survival skills in their intellectual arsenal
included an ability to remember complex travel routes and to identify
potentially edible and possibly lethal plants, Gosden says.


Swift settlement of southern as well as northern Sahul occurred
shortly after 50,000 years ago (SN: 3/15/03, p. 173), proposes
archaeologist Matthew Spriggs of Australian National University in
Canberra. “Finding the first human sites is a bit of a needle-in-the-
haystack problem, but people in northern Sahul could have walked to
and from what we now know as Australia,” he says.


Previous reports that people reached northern Australia at least
60,000 years ago, based on measurements of stored radiation that
indicate when an artifact was buried, have drawn skepticism because of
possible shifting of sediment layers and artifacts over time.


Prior research on Papua New Guinea, conducted by Summerhayes and
others, has located human occupations with radiocarbon dates as old as
41,000 years along the coast and at one Ivane Valley site.


In 2007 and 2008, Summerhayes’ team found seven more ancient camps in
the highland valley. Radiocarbon measures of charcoal from one site,
Vilakuav, put it at between 49,000 and 43,000 years old. Other sites
dated to between 41,400 and 26,000 years ago.


Each camp yielded various stone tools. Investigators found sharp
implements indented in the middle, known as waisted axes, at four
sites, including Vilakuav. Already known from later Stone Age sites on
Papua New Guinea, waisted axes were used to clear trees and open
patches of forest to sunlight so that edible and medicinal plants
could grow faster, Summerhayes suggests.


Sahul settlers made stone tools where they camped, he notes. Finds
included large stones from which sharp flakes had been removed and
shards of rock produced during toolmaking.


Starch grains found on several stone tools came from yams, a food that
must have been gathered in its natural range at lower altitudes, the
researchers say.


Charred nut shells from high-altitude Pandanus trees turned up at
Vilakuav and at three other sites. Ancient settlers ate these nuts and
probably a pineapple-like fruit that grows on Pandanus trees, the
scientists suspect.


Excavations at Vilakuav also produced burned bone fragments from
unidentified animals that had been hunted, in Summerhayes’ view.
Available game probably included animals still found in the region —
possums, tree kangaroos, bats, frogs, anteaters, lizards, snakes and
birds.


Farming began in Papua New Guinea’s highlands about 9,000 years ago.
Today, Gosden points out, farming populations thrive where small bands
of foragers once scrounged out a living.




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