July 9, 2012 — Vol. 28 No. 24
A potential corridor along the coast of Alaska for humans to travel down to populate the New World was open and free of ice 1,500 to 2,000 years earlier than what was previous thought, according to a new study completed by Oregon State University and Idaho State University researchers.
"We dated core samples of lakes on Sanak Island, which would have been near the ocean shore at that time, and we determined the coast here was free of ice between 16,000 and 17,000 years ago, about 2,000 years earlier than what was previously thought," said Bruce Finney, ISU biological and geosciences professor.
This study has important implications for anthropologists and archeologists.
Many archeologists believe that the Americas were populated about 15,000 years ago or longer, but it was assumed that migrants from Asia couldn't come down the coast of the Alaska Peninsula prior to 13,000 years ago because it was covered by a massive sheet of ice, said Herbert Maschner, director of the Idaho State University Museum of Natural History.
"These new findings, however, indicate that this area was free of ice and fully vegetated as early as 16,000 to 17,000 years ago," Maschner said, "People could have migrated down the coast during this time, which correlates to the time of earlier archeological sites discovered in North and South America."
The ISU researchers pointed out that no evidence of human travel during this time frame has been found on Sanak Island, where the oldest known human activity is 6,000 to 7,000 years ago. However, the discovery that the ice left earlier than was previously thought - and when it was there was only half as thick as previously thought -- establishes that such migrations were possible.
Maschner, Finney and Mark Shapley were three of four ISU scientists who participated on the study "Early retreat of the Alaska Peninsula Glacier Complex and the implications for coastal migrations of First Americans" that was published in the journal "Quaternary Science Reviews" this month. That study has been publicized widely internationally in scientific and popular news outlets.
The study's lead author, Nicole Misarti, currently of the Oregon State University College of Earth, Ocean and Atmospheric Sciences, began the study during her Ph.D. research under Finney's supervision at the University of Alaska Fairbanks, and completed it while an ISU post-doctoral researcher working on the National Science Foundation Sanak Island Biocomplexity Project.
The Sanak Island is located about 40 miles from the coast of western Alaska Peninsula, about 700 miles southwest of Anchorage, Alaska.