By Bruce Bower
Southern Chile lies near the bottom of the world, but it sits atop scientific efforts to unravel how and when the Americas were first settled. New evidence unearthed at Chile’s Monte Verde site supports the idea that prehistoric people moved slowly down the Pacific Coast — beginning well before 14,000 years ago — and established many inland outposts along the way.
A team led by archaeologist Tom Dillehay of Vanderbilt University in Nashville unearthed ample remains of nine seaweed species — including five species not found before at Monte Verde — from hearths and other parts of two hutlike structures. Radiocarbon measurements of seaweed remnants yielded an age estimate ranging from 14,220 to 13,980 years ago.
That finding buttresses Dillehay’s controversial 1997 report, based on radiocarbon dating of bones and charcoal, that people inhabited Monte Verde by 14,000 years ago. The southern Chilean site, located 30 kilometers from the coast, was occupied more than 1,000 years earlier than any other reliably dated settlement in the Americas, the researchers conclude in the May 9 Science.
“Finding seaweed wasn’t a surprise, but finding five new species in the abundance that we found them was a surprise,” Dillehay says. “The Monte Verdeans were really like beachcombers and apparently had a tradition of exploiting coastal resources.”
Whereas some types of seaweed at Monte Verde came from the coast, others derived from an inland bay situated six kilometers south of the settlement.
The seaweed species recovered at Monte Verde all represent good sources of iodine, iron, zinc and other nutrients. These seaweeds also promote cholesterol metabolism, bone strength and the body’s ability to fight infection. Local populations still use certain seaweed species found at Monte Verde to treat common health problems.
Dillehay’s team also recovered three stone tools, one of which contains microscopic seaweed fragments on its edge. Ancient residents used this implement to cut and prepare seaweed, the researchers suggest.
Because Monte Verde also contains remains of nearby animals, vegetables and nuts, Dillehay suspects that ancient people moved back and forth from the coast to the inland site.
If other early New World migrants traveled down the PacificCoast from Alaska to South America, they may have stopped along the way to reap the bounties of hundreds of inland river basins, Dillehay proposes. That process began more than 16,000 years ago, in his view. “The peopling of the Americas may not have been the blitzkrieg movement to the south that researchers have assumed, but a much slower and more deliberate process,” he says.
Jon Erlandson of the University of Oregon in Eugene agrees. He hypothesizes that people could have moved slowly down the PacificCoast, exploiting a range of resources from kelp forests just off the coast. “The new Monte Verde research provides a nice seaweed garnish for this coastal migration theory,” he says.
Dillehay’s results challenge the longstanding view that New World colonization began no more than 13,000 years ago and reached South America perhaps a millennium later as groups of big game hunters followed herds south.
The new study verifies that people lived at Monte Verde 14,000 years ago, remarks archaeologist Daniel Sandweiss of the University of Maine in Orono. Until now, Sandweiss had been skeptical of that claim.
“The model of slow migration with inland forays is intriguing and quite possibly right,” Sandweiss says. To test that hypothesis, scientists need to find evidence of other ancient inland sites that contain coastal resources, in his view. Sea-level rises have probably submerged most coastal settlements from Monte Verde’s time.