High-tech undersea search for the first Americans
Ocean archeologist Robert Ballard is searching the floor of the Gulf of Mexico, via remote control.
By Moises Velasquez-Manoff | Correspondent of The Christian Science Monitor
MYSTIC, CONN. - Inside a darkened room, oceanographer Robert Ballard stares at an array of flat-screen monitors. The monitor to his left shows a crew of scientists aboard the submarine support vessel Carolyn Chouest in the Gulf of Mexico. On a monitor to his right, a roomful of Rhode Island high school students are intently focused on something unseen. And directly ahead, a large plasma TV plays live footage of what's holding everyone's attention: the ocean floor some 115 miles off the Texas coast.
The picture is transmitted by Argus, an unmanned submersible 1,800 miles away from the Mystic Aquarium in Connecticut. In fact, Dr. Ballard is presiding over the first undersea expedition conducted entirely by remote control. "It's the first time I've had enough confidence in the technology to step ashore," he says.
The subject of his search, as well as its location, are as precedent-setting as the means he's using to conduct it.
Enabled by technological advances such as satellite uplinks and the next generation of Internet, the expedition is a step toward Ballard's vision of a world experienced via "telepresence" ? not in person, but via remotely operated cameras and sensors. It's cheaper, requiring less manpower than typical science expeditions. It also has profound implications for any kind of undersea exploration, especially for the nascent field of ocean archaeology.
Today, Ballard and his team are seeking submerged evidence of the first Americans. Any proof of past human habitation in this area of former coastline could sink a long-dominant ? and many say hopelessly eroded ? hypothesis about who the first Americans were, how they got here, and when they arrived.
"It's a great story in human history," says Kevin McBride, a professor of anthropology at the University of Connecticut at Storrs, who is involved in the project. "And as usual, it's a more complicated story than people think."
With the help of the US Navy's only research submarine, NR-1, Ballard's team is mapping the area to determine where early Americans might have lived when the Gulf's underwater hills sat at shoreline. At the height of the last ice age, sea levels were nearly 400 feet lower than they are today. The team's voyage began March 4, along a series of rises called the Flower Garden Banks. Scientists think the area, now filled with colorful sponges and abundant sea life, was a thriving coastal estuary 19,000 years ago ? and prime real estate for human habitation.
Dwellers on an ancient coast
An abundant amount of salt left from an even earlier time when a closed-off Gulf of Mexico completely evaporated would have provided an invaluable resource for preserving meat. Salt licks also would have attracted grazing animals and potential game. Inhabitants would have also found the coastal estuary full of easily harvestable shellfish, and if they ate shellfish, they probably left behind large piles of discarded shells that scientists can radiocarbon date. Because of the continental shelf's gradual incline in the area, rising seas would have quickly inundated the land, increasing the chances that artifacts were preserved.
This is Ballard's high-tech quest: proof of human habitation in the Gulf. That might refute the classic hypothesis that the first humans in the Americas were Siberian hunters, who followed herds over the Bering land bridge some 11,500 years ago. The hunters, the theory goes, passed into the interior of the continent via an ice-free corridor on the east side of the Canadian Rockies. Archaeologists call them the Clovis culture, after a distinctive spear point found near Clovis, N.M., in the 1930s.
But in the past 20 years, archaeologists have excavated many sites with radiocarbon dates older than the Clovis culture. Tools and shelters at Monte Verde in Chile are 12,500 years old. Stone flakes and fire pits found at the Meadowcroft Rockshelter in Pennsylvania date to 14,000 years ago ? before the corridor to the interior would have been open. This observation gave birth to an alternate hypothesis: Perhaps the first Americans skirted the glaciers in boats.
An ice-free corridor inland
Bolstering this possibility, scientists now think that a sliver of coast between the great Cordilleran glacier on the Canadian Rockies and the Pacific Ocean remained clear during the Ice Age.
In 1997, Daryl Fedje of the Canadian Parks service pulled up a stone tool from the seafloor 170 feet down. The tool could have fallen there, but the seafloor itself, which was dotted with tree stumps and littered with pine cones, was clear evidence of an inhabitable ice age forest along the coast. Early seafarers could have occasionally pulled up to land during their migration.
But nothing has complicated the picture more than genetic evidence. Studies of native American groups indicate that up to five waves of people arrived at different times. Four of them ? A, B, C, and D ? are related to populations in Asia. Several of these groups share genetic markers with people in modern-day Indonesia, Australia, and the Pacific Islands ? places scientists think were settled by seafaring people.
Further confusing the picture, this fifth group, called "X," also shares genetic markers with European populations. Although controversial, this evidence lends credence to another, stranger possibility: Stone Age Europeans sailed west and made landfall in what was, even then, a land of immigrants.
New methods produce new data
"Sometimes methodology explodes and theory plays catch-up," says James Adovasio, executive director of the Mercyhurst Archaeological Institute at Mercyhurst College in Erie, Pa., and the archaeologist who excavated Meadowcroft. "We're living at a time when the methodological techniques are exploding, and as they generate new, higher-resolution data, we have to reformulate how we think about stuff."
At stake in any undersea archaeological find is more than just the timing and chronology of the peopling of the Americas, says Professor Adovasio. Evidence of a seafaring culture in the Americas before the Clovis culture would overturn longstanding notions of our Stone Age forebears. Rather than a society of fur-clad, spear-wielding hunters stabbing mammoths, the first Americans may have been coastal dwellers, he says, a difference with great implications for everything from the division of labor in their society to the tools they used.
"Let us suppose that they find offshore campsites that are 16,000 years old," says Adovasio. "It would put yet another nail into the Clovis sarcophagus."
'Telepresence' may let scientists - and tourists - be everywhere at once
In 1979, Robert Ballard found the first "black smokers," undersea vents spewing black sulfides near the Galapagos Islands. In 1985, he cemented his fame with the discovery of the Titanic in the north Atlantic.
Now, Dr. Ballard wants to change ? and enhance ? how everyone from scientists to schoolchildren explores the planet. Using a combination of remotely operated vehicles and cameras, he sees a future where "electronic travel" lets anyone look in on Earth's hard-to-reach corners with minimal cost and effort.
"It's not critical that your gall bladder gets to the Serengeti," he says. But "your spirit has no mass; you can move your spirit around cheaply."
On expeditions, remotely operated vehicles will scour the seafloor thousands of miles away 24/7. Individuals on rotating shifts will monitor the images. Only when something interesting comes into view will an on-call scientist assume command.
For the layperson, remotely operated cameras left behind will provide live video of everything from African plains to ocean canyons. Not only will this "telepresence" give the average student real-time access to the planet's mysteries, it will also lessen humanity's impact on the natural wonders we so eagerly wish to view.
None of this would be possible were it not for the emerging Internet2 protocol, says Ballard. Enabled by a nationwide network of fiber-optic cables, the I-2 is up to 10,000 times faster than the average broadband connection ? 10 gigabits per second ? and allows for the live transmission of high-definition video.
In 2002, Ballard installed his first remotely operated camera in California's Monterey Bay. Children at his Institute for Exploration at the Mystic Aquarium in Mystic, Conn., could control an underwater vehicle 3,000 miles away. Remote cameras are slated for the Channel Islands off California, Hawaii and in the Florida Keys.
On the Flower Garden Banks expedition to the Gulf of Mexico (see main story), the public could tune in to one of the four live broadcasts online daily and submit questions in real time.
http://www.csmonitor.com/2007/0314/p13s01-stgn.html?page=1
