http://www.time.com/time/magazine/printout/0,8816,1169905,00.html
Time, Sunday, Mar. 05, 2006
Who Were The First Americans?
They may have been a lot like Kennewick Man, whose hotly disputed
bones are helping rewrite our earliest history. An exclusive inside
look
By MICHAEL D. LEMONICK, ANDREA DORFMAN
It was clear from the moment Jim Chatters first saw the partial
skeleton that no crime had been committed--none recent enough to be
prosecutable, anyway. Chatters, a forensic anthropologist, had been
called in by the coroner of Benton County, Wash., to consult on some
bones found by two college students on the banks of the Columbia
River, near the town of Kennewick. The bones were obviously old, and
when the coroner asked for an opinion, Chatters' off-the-cuff guess,
based on the skull's superficially Caucasoid features, was that they
probably belonged to a settler from the late 1800s. =E2=80=A2 Then a CT sca=
n
revealed a stone spear point embedded in the skeleton's pelvis, so
Chatters sent a bit of finger bone off to the University of California
at Riverside for radiocarbon dating. When the results came back, it
was clear that his estimate was dramatically off the mark. The bones
weren't 100 or even 1,000 years old. They belonged to a man who had
walked the banks of the Columbia more than 9,000 years ago.
In short, the remains that came to be known as Kennewick Man were
almost twice as old as the celebrated Iceman discovered in 1991 in an
Alpine glacier, and among the oldest and most complete skeletons ever
found in the Americas. Plenty of archaeological sites date back that
far, or nearly so, but scientists have found only about 50 skeletons
of such antiquity, most of them fragmentary. Any new find can thus add
crucial insight into the ongoing mystery of who first colonized the
New World--the last corner of the globe to be populated by humans.
Kennewick Man could cast some much needed light on the murky questions
of when that epochal migration took place, where the first Americans
originally came from and how they got here.
U.S. government researchers examined the bones, but it would take
almost a decade for independent scientists to get a good look at the
skeleton. Although it was found in the summer of 1996, the local
Umatilla Indians and four other Columbia Basin tribes almost
immediately claimed it as ancestral remains under the Native American
Graves Protection and Repatriation Act (see box), demanding that the
skeleton be reburied without the desecration of scientific study. A
group of researchers sued, starting a legal tug-of-war and
negotiations that ended only last summer, with the scientists getting
their first extensive access to the bones. And now, for the first
time, we know the results of that examination.
WHAT THE BONES REVEALED
It was clearly worth the wait. The scientific team that examined the
skeleton was led by forensic anthropologist Douglas Owsley of the
Smithsonian Institution's National Museum of Natural History. He has
worked with thousands of historic and prehistoric skeletons, including
those of Jamestown colonists, Plains Indians and Civil War soldiers.
He helped identify remains from the Branch Davidian compound in Texas,
the 9/11 attack on the Pentagon and mass graves in Croatia.
In this case, Owsley and his team were able to nail down or make
strong guesses about Kennewick Man's physical attributes. He stood
about 5 ft. 9 in. tall and was fairly muscular. He was clearly
right-handed: the bones of the right arm are markedly larger than
those of the left. In fact, says Owsley, "the bones are so robust that
they're bent," the result, he speculates, of muscles built up during a
lifetime of hunting and spear fishing.
An examination of the joints showed that Kennewick Man had arthritis
in the right elbow, both knees and several vertebrae but that it
wasn't severe enough to be crippling. He had suffered plenty of trauma
as well. "One rib was fractured and healed," says Owsley, "and there
is a depression fracture on his forehead and a similar indentation on
the left side of the head." None of those fractures were fatal,
though, and neither was the spear jab. "The injury looks healed," says
Owsley. "It wasn't a weeping abscess." Previous estimates had
Kennewick Man's age as 45 to 55 when he died, but Owsley thinks he may
have been as young as 38. Nothing in the bones reveals what caused his
demise.
But that's just the beginning of an impressive catalog of information
that the scientists have added to what was already known--all the more
impressive given the limitations placed on the team by the U.S. Army
Corps of Engineers, which is responsible for the skeleton because the
Corps has jurisdiction over the federal land on which it was found.
The researchers had to do nearly all their work at the University of
Washington's Burke Museum, where Kennewick Man has been housed in a
locked room since 1998, under the watchful eyes of representatives of
both the Corps and the museum, and according to a strict schedule that
had to be submitted in advance. "We only had 10 days to do everything
we wanted to do," says Owsley. "It was like a choreographed dance."
Perhaps the most remarkable discovery: Kennewick Man had been buried
deliberately. By looking at concentrations of calcium carbonate left
behind as underground water collected on the underside of the bones
and then evaporated, scientists can tell that he was lying on his back
with his feet rolled slightly outward and his arms at his side, the
palms facing down--a position that could hardly have come about by
accident. And there was no evidence that animal scavengers had been at
the body.
The researchers could also tell that Kennewick Man had been buried
parallel to the Columbia, with his left side toward the water: the
bones were abraded on that side by water that eroded the bank and
eventually dumped him out. It probably happened no more than six
months before he was discovered, says team member Thomas Stafford, a
research geochemist based in Lafayette, Colo. "It wouldn't have been
as much as a year," he says. "The bones would have been more widely
dispersed."
The deliberate burial makes it especially frustrating for scientists
that the Corps in 1998 dumped hundreds of tons of boulders, dirt and
sand on the discovery site--officially as part of a project to combat
erosion along the Columbia River, although some scientists suspect it
was also to avoid further conflict with the local tribes. Kennewick
Man's actual burial pit had already been washed away by the time
Stafford visited the site in December 1997, but a careful survey might
have turned up artifacts that could have been buried with him. And if
his was part of a larger burial plot, there's now no way for
archaeologists to locate any contemporaries who might have been
interred close by.
Still, the bones have more secrets to reveal. They were never
fossilized, and a careful analysis of their carbon and nitrogen
composition, yet to be performed, should reveal plenty about Kennewick
Man's diet. Says Stafford: "We can tell if he ate nothing but plants,
predominantly meat or a mixture of the two." The researchers may be
able to determine whether he preferred meat or fish. It's even
possible that DNA could be extracted and analyzed someday.
While the Corps insisted that most of the bones remain in the museum,
it allowed the researchers to send the skull fragments and the right
hip, along with its embedded spear point, to a lab in Lincolnshire,
Ill., for ultrahigh-resolution CT scanning. The process produced
virtual slices just 0.39 mm (about 0.02 in.) thick--"much more
detailed than the ones made of King Tut's mummy," says Owsley. The
slices were then digitally recombined into 3-D computer images that
were used to make exact copies out of plastic. The replica of the
skull has already enabled scientists to clear up a popular
misconception that dates back to the initial reports of the discovery.
WAS KENNEWICK MAN CAUCASIAN?
Thanks to Chatters' mention of Caucasoid features back in 1996, the
myth that Kennewick Man might have been European never quite died out.
The reconstructed skull confirms that he was not--and Chatters never
seriously thought otherwise. "I tried my damnedest to curtail that
business about Caucasians in America early," he says. "I'm not talking
about today's Caucasians. I'm saying they had 'Caucasoid-like'
characteristics. There's a big difference." Says Owsley: "[Kennewick
Man] is not North American looking, and he's not tied in to Siberian
or Northeast Asian populations. He looks more Polynesian or more like
the Ainu [an ethnic group that is now found only in northern Japan but
in prehistoric times lived throughout coastal areas of eastern Asia]
or southern Asians."
That assessment will be tested more rigorously when researchers
compare Kennewick Man's skull with databases of several thousand other
skulls, both modern and ancient. But provisionally, at least, the
evidence fits in with a revolutionary new picture that over the past
decade has utterly transformed anthropologists' long-held theories
about the colonization of the Americas.
WHO REALLY DISCOVERED AMERICA?
The conventional answer to that question dates to the early 1930s,
when stone projectile points that were nearly identical began to turn
up at sites across the American Southwest. They suggested a single
cultural tradition that was christened Clovis, after an
11,000-year-old-plus site near Clovis, N.M. And because no older sites
were known to exist in the Americas, scientists assumed that the
Clovis people were the first to arrive. They came, according to the
theory, no more than 12,000 years B.P. (before the present), walking
across the dry land that connected modern Russia and Alaska at the end
of the last ice age, when sea level was hundreds of feet lower than it
is today. From there, the earliest immigrants would have made their
way south through an ice-free corridor that geologists know cut
through what are now the Yukon and Mackenzie river valleys, then along
the eastern flank of the Canadian Rockies to the continental U.S. and
on to Latin America.
That's the story textbooks told for decades--and it's almost certainly
wrong. The first cracks in the theory began appearing in the 1980s,
when archaeologists discovered sites in both North and South America
that seemed to predate the Clovis culture. Then came genetic and
linguistic analyses suggesting that Asian and Native American
populations diverged not 12,000 years ago but closer to 30,000 years
ago. Studies of ancient skulls hinted that the earliest Americans in
South America had different ancestors from those in the North.
Finally, it began to be clear that artifacts from Northeast Asia
dating from just before the Clovis period and South American artifacts
of comparable age didn't have much in common with Clovis artifacts.
Those discoveries led to all sorts of competing theories, but few
archaeologists or anthropologists took them seriously until 1997. In
that year, a blue-ribbon panel of researchers took a hard look at
evidence presented by Tom Dillehay, then at the University of
Kentucky, from a site he had been excavating in Monte Verde, Chile.
After years of skepticism, the panel finally affirmed his claim that
the site proved humans had lived there 12,500 years ago. "Monte Verde
was the turning point," says David Meltzer, a professor of prehistory
at Southern Methodist University in Dallas who was on the panel. "It
broke the Clovis barrier."
Why? Because if people were living in southern Chile 12,500 years ago,
they must have crossed over from Asia considerably earlier, and that
means they couldn't have used the ice-free inland corridor; it didn't
yet exist. "You could walk to Fairbanks," says Meltzer. "It was
getting south from Fairbanks that was a problem." Instead, many
scientists now believe, the earliest Americans traveled down the
Pacific coast--possibly even using boats. The idea has been around for
a long time, but few took it seriously before Monte Verde.
One who did was Jon Erlandson, an archaeologist at the University of
Oregon, whose work in Daisy Cave on San Miguel Island in California's
Channel Island chain uncovered stone cutting tools that date to about
10,500 years B.P., proving that people were traveling across the water
at least that early. More recently, researchers at the Santa Barbara
Museum of Natural History redated the skeletal remains of an
individual dubbed Arlington Springs Woman, found on another of the
Channel Islands, pushing her age back to about 11,000 years B.P.
Farther south, on Cedros Island off the coast of Baja California, U.C.
at Riverside researchers found shell middens--heaps of kitchen waste,
essentially--and other materials that date back to the same period as
Daisy Cave. Down in the Andes, researchers have found coastal sites
with shell middens dating to about 10,500 years B.P.
And in a discovery that offers a sharp contrast to the political
hoopla over Kennewick Man, scientists and local Tlingit and Haida
tribes cooperated so that researchers could study skeletal remains
found in On Your Knees Cave on Prince of Wales Island in southern
Alaska. "There's no controversy," says Erlandson, who has investigated
cave sites in the same region. "It hardly ever hits the papers." Of
about the same vintage as Kennewick Man and found at around the same
time, the Alaskan bones, along with other artifacts in the area, lend
strong support to the coastal-migration theory. "Isotopic analysis of
the human remains," says James Dixon, the University of Colorado at
Boulder anthropologist who found them, "demonstrates that the
individual--a young male in his early 20s--was raised primarily on a
diet of seafood."
CRUISING DOWN THE KELP HIGHWAY
Erlandson has found one more line of evidence that supports the
migration theory. While working with a group of marine ecologists, he
was startled to learn that there were nearly continuous kelp forests
growing just offshore all the way from Japan in the western Pacific to
Alaska and down the West Coast to Baja California, then (with a gap in
the tropics) off the coast of South America. In a paper presented
three weeks ago, he outlined the potential importance to the earliest
Americans of what he calls the "kelp highway."
"Most of the early sites on the west coast are found adjacent to kelp
forests, even in Peru and Chile," he says. "The thing about kelp
forests is they're extremely productive." They not only provide
abundant food, from fish, shellfish, seals and otters that thrive
there, but they also reduce wave energy, making it easier to navigate
offshore waters. By contrast, the inland route along the ice-free
corridor would have presented travelers with enormous ecological
variability, forcing them to adapt to new conditions and food sources
as they traveled.
Unfortunately, the strongest evidence for the coastal theory lies
offshore, where ancient settlements would have been submerged by
rising seas over the past 10,000 years or so. "Artifacts have been
found on the continental shelves," says Dixon, "so I'm quite confident
there's material out there." But you need submersible craft to search,
and, he says, that type of research is a very hard sell to the people
who own and operate that kind of equipment. "The maritime community is
interested in shipwrecks and treasures. A little bit of charcoal and
some rocks on the ocean floor is not very exciting to them."
MULTIPLE MIGRATIONS
Even if the earliest Americans traveled down the coast, that doesn't
mean they couldn't have come through the interior as well. Could there
have been multiple waves of migration along a variety of different
routes? One way scientists have tried to get a handle on that question
is through genetics. Their studies have focused on two different types
of evidence extracted from the cells of modern Native Americans:
mitochondrial DNA, which resides outside the nuclei of cells and is
passed down only through the mother; and the Y chromosome, which is
passed down only from father to son. Since DNA changes subtly over the
generations, it serves as a sort of molecular clock, and by measuring
differences between populations, you can gauge when they were part of
the same group.
Or at least you can try. Those molecular clocks are still rather
crude. "The mitochondrial DNA signals a migration up to 30,000 years
ago," says research geneticist Michael Hammer of the University of
Arizona. "But the Y suggests that it occurred within the last 20,000
years." That's quite a discrepancy. Nevertheless, Hammer believes that
the evidence is consistent with a single pulse of migration.
Theodore Schurr, director of the University of Pennsylvania's
Laboratory of Molecular Anthropology, thinks there could have been
many migrations. "It looks like there may have been one primary
migration, but certain genetic markers are more prevalent in North
America than in South America," Schurr explains, suggesting secondary
waves. At this point, there's no definitive proof of either idea, but
the evidence and logic lean toward multiple migrations. "If one
migration made it over," Dillehay, now at Vanderbilt University, asks
rhetorically, "why not more?"
OUT OF SIBERIA?
Genetics also points to an original homeland for the first
Americans--or at least it does to some researchers. "Skeletal remains
are very rare, but the genetic evidence suggests they came from the
Lake Baikal region" of Russia, says anthropologist Ted Goebel of the
University of Nevada at Reno, who has worked extensively in that part
of southern Siberia. "There is a rich archaeological record there," he
says, "beginning about 40,000 years ago." Based on what he and Russian
colleagues have found, Goebel speculates that there were two northward
migratory pulses, the first between 28,000 and 20,000 years ago and a
second sometime after 17,000 years ago. "Either one could have led to
the peopling of the Americas," he says.
Like just about everything else about the first Americans, however,
this idea is open to vigorous debate. The Clovis-first theory is
pretty much dead, and the case for coastal migration appears to be
getting stronger all the time. But in a field so recently liberated
from a dogma that has kept it in an intellectual straitjacket since
Franklin Roosevelt was President, all sorts of ideas are suddenly on
the table. Could prehistoric Asians, for example, have sailed directly
across the Pacific to South America? That may seem far-fetched, but
scientists know that people sailing from Southeast Asia reached
Australia some 60,000 years ago. And in 1947 the explorer Thor
Heyerdahl showed it was possible to travel across the Pacific by raft
in the other direction.
At least a couple of archaeologists, including Dennis Stanford of the
Smithsonian, even go so far as to suggest that the earliest Americans
came from Europe, not Asia, pointing to similarities between Clovis
spear points and blades from France and Spain dating to between 20,500
and 17,000 years B.P. (Meltzer, Goebel and another colleague recently
published a paper calling this an "outrageous hypothesis," but
Dillehay thinks it's possible.)
All this speculation is spurring a new burst of scholarship about
locations all over the Americas. The Topper site in South Carolina,
Cactus Hill in Virginia, Pennsylvania's Meadowcroft, the Taima-Taima
waterhole in Venezuela and several rock shelters in Brazil all seem to
be pre-Clovis. Dillehay has found several sites in Peru that date to
between 10,000 and 11,000 years B.P. but have no apparent links to the
Clovis culture. "They show a great deal of diversity," he says,
"suggesting different early sources of cultural development in the
highlands and along the coast."
It's only by studying those sites in detail and continuing to search
for more evidence on land and offshore that these questions can be
fully answered. And as always, the most valuable evidence will be the
earthly remains of the ancient people themselves. In one 10-day
session, Kennewick Man has added immeasurably to anthropologists'
store of knowledge, and the next round of study is already under way.
If scientists treat those bones with respect and Native American
groups acknowledge the importance of unlocking their secrets, the
mystery of how and when the New World was populated may finally be
laid to rest. Coming To America For decades, scientists thought the
New World was populated by migrants from Asia who wandered down the
center of the continent about 12,000 years ago. New discoveries are
pushing that theory out to sea Three views on how humans populated the
Americas =E2=80=A2 COASTAL Recent finds at Daisy Cave, Calif., and Monte
Verde, Chile, point to bands of people moving down the Pacific coast
of North and South America much earlier, perhaps 30,000 years ago
=E2=80=A2 OVERLAND Discoveries at Clovis, N.M., led to the theory that a
single human culture moved into the Americas down the eastern side of
the Rocky Mountains about 12,000 years ago
=E2=80=A2 ATLANTIC Artifacts found in South Carolina have led some
archaeologists to speculate that early migrants might have arrived on
the East Coast from Europe, although the evidence remains in dispute
Select
archaeological sites*:
=E2=80=A2 Other artifacts found Ushki Lake RUSSIA 11,000 B.P. =E2=80=A2 Hum=
an
remains found On Your Knees Cave ALASKA 9,818 B.P. =E2=80=A2 Human remains
found Kennewick WASH. 9,400 B.P.
=E2=80=A2 Other artifacts found Daisy Cave CALIF. 10,500 B.P.
=E2=80=A2 Other artifacts found Cedros Island MEXICO 11,000 B.P.
=E2=80=A2 Other artifacts found Folsom N.M. 10,490 B.P.
=E2=80=A2 Other artifacts found Clovis N.M. 11,200 B.P. =E2=80=A2 Dates in =
dispute
Meadowcroft PA. 14,250 B.P. =E2=80=A2 Dates in dispute Cactus Hill VA.
15,070 B.P. =E2=80=A2 Dates in dispute Topper S.C. 15,200 B.P. =E2=80=A2 Da=
tes in
dispute Taima-Taima VENEZUELA 13,000 B.P.
=E2=80=A2 Other artifacts found Pedra Furada BRAZIL 47,000 B.P.
=E2=80=A2 Other artifacts found Lapa do Boquete BRAZIL Up to 12,070 B.P.
=E2=80=A2 Other artifacts found Tibit COLOMBIA 11,740 B.P.
=E2=80=A2 Other artifacts found Quebrada Jaguay PERU 10,500 B.P.
=E2=80=A2 Other artifacts found Monte Verde CHILE 12,500 B.P.
=E2=80=A2 Human remains found Palli Aike CHILE 8,640 B.P. Tools in the sear=
ch
ARCHAEOLOGY Skeletons like Kennewick Man are rare. More often
scientists study and date other indications of human activity --
remains of butchered animals, stone tools, spear points or even bits
of burned charcoal. Unfortunately, such artifacts may never be found
along coastal migration routes --=C2 they're now under water
GENETICS Scientists use markers in DNA samples from indigenous peoples
in North and South America to figure out when populations diverged
from each other. DNA comparisons suggest the first Americans may have
diverged from groups in the Lake Baikal area of what is now Russia as
early as 26,000 years ago
LINGUISTICS By studying native words and grammar, scientists can
establish links and infer the amount of time required for different
languages to evolve from a common origin. As of 1492, there were an
estimated 1,000 languages in the Americas that may have developed from
the original migrants
Migration milestones
=E2=80=A2 30,000 B.P.* Beginning of last North American ice age.
Mitochondrial-DNA studies indicate the earliest possible migration
=E2=80=A2 25,000 Approximate opening of Bering land bridge between Asia and
North America =E2=80=A2 20,000 Earliest migration date, according to
Y-chromosome studies =E2=80=A2 15,000 Evidence of humans in South America
Glacial melting floods Bering land bridge =E2=80=A2 10,000 End of last ice
age in North America Kennewick Man lives in Pacific Northwest =E2=80=A2
5,000 Dawn of Central American cultures such as Olmec and Maya =E2=80=A2
Present
*Dates are in radiocarbon years "before the present," a scientific
standard meaning "before 1950"
=C2
With reporting by With reporting by Dan Cray/Los Angeles
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