Washington, May 9 : Ancient seaweed samples from the Monte Verde archaeological site in southern Chile has confirmed its status as the earliest known human settlement in the Americas, dating back to 14,000 years.
It also provides additional support for the theory that one early migration route followed the Pacific Coast more than 14,000 years ago.
The study was conducted by a team of anthropologists, geologists and botanists headed by Vanderbilt University's Distinguished Professor of Anthropology Tom Dillehay.
The study, which includes the first new data reported from the site in 10 years, includes the identification of nine species of seaweed and marine algae recovered from hearths and other areas in the ancient settlement.
The seaweed samples were directly dated between 14,220 to 13,980 years ago, confirming that the upper layer of the site, labeled Monte Verde II, was occupied more than 1,000 years earlier than any other reliably dated human settlements in the Americas.
The Monte Verde site was discovered in 1976. It is located in a peat bog about 500 miles south of Santiago and has revealed well-preserved ruins of a small settlement of 20 to 30 people living in a dozen huts along a small creek.
In 1979, when Dillehay and his colleagues first reported that the radiocarbon dating of the bones and charcoal found at Monte Verde returned dates of more than 14,000 years before the present, it stirred up a major controversy because the early dates appeared to conflict with other archaeological evidence of the settlement of North America.
It wasn't until 1997 that the controversy was resolved by a prominent group of archaeologists who reviewed the evidence, visited the Monte Verde site and unanimously approved the dating.
Most scholars now believe that people first entered the new world through the Bering land bridge more than 16,000 years ago. After entering Alaska, it is not known whether they colonized the hemisphere by moving down the Pacific coast, by inland routes or both.
The general view is that the early immigrants would have spread down the coast much faster than they could move inland because they could exploit familiar coastal resources more readily and get much of their food from the sea.
Evidence to support the coastal migration theory has now come up with the findings of the ancient seaweed.
"The number and frequency of these items suggests very frequent contact with the coast, as if they had a tradition of exploiting coastal resources," said Dillehay.