Archaeologists have hypothesized that more than 4,500 years ago, communities on barrier islands along the southeastern coastlines of the North America were abruptly abandoned due to a sudden shift in climate. But new research from the University of Georgia Laboratory of Archaeology indicates that environmental change was happening both during the settlement of these island villages and—over centuries longer than previously believed—during their gradual decline. Moreover, the evidence shows that the Native Americans who lived in those villages showed considerable resilience in adapting to the changes around them.
Our colleagues in the Office of Research share details about the new study:
In a paper published on PLOS ONE, UGA archaeologists Carey Garland and Victor Thompson (along with several co-authors) describe using multiple methodologies to show that climate change was occurring along the Georgia coastline in the years from 4,500 to 3,800 before present (BP). These changes affected the size and availability of the marine creatures that provided sustenance to the island culture, which then resulted in the abandonment of former villages for areas of the coast not previously settled.
“We’re not just looking at climate—we’re looking at the interaction between the environment and the people, and how they adapted to this,” said postdoctoral researcher Garland. “It was originally thought that people abandoned these shell rings because of climate instability, but our findings show that there was climate instability the whole time they were occupied.”
The study focused on the Sapelo Shell Ring Complex, a group of three shell-ring villages on Sapelo Island, about 70 miles south of Savannah, Georgia. The first and largest of these villages, with an encircled area of about 6,000 square meters, was founded around 4,250 BP. Occupation of the three villages overlapped, and the third and smallest ring appears to have been abandoned by 3,755 BP.
Over those 500 years, the Native American inhabitants were forced to deal with falling sea and salinity levels in the coastal estuaries that served as their prime fishing grounds. These environmental conditions reduced the size and number of the oysters and other fish and mollusks that served as one of the villagers’ main food sources (these cultures predate the use of agriculture along the southeastern coast).
Map courtesy of the UGA Laboratory of Archaeology