Underwater Dig Finds Proof Humans Settled U.S. Earlier Than Thought

Archaeologist Valrie Brosseau prepares to descend to the Page-Ladson site. Brendan Fenerty
Archaeologist Valrie Brosseau prepares to descend to the Page-Ladson site. Brendan Fenerty


The term "archaeologist" conjures thoughts of a dusty-hatted Indiana Jones, searching for ruins in deserts or caves. But a wetsuit and scuba tank? That's just how scientists have made one of the most compelling recent finds at the oldest underwater archaeological site in the Americas, proving people lived in the Southeastern United States much longer ago than previously believed.

Scientists spent 2012 to 2014 burrowing into sediment under the Aucilla River in Florida. To access the Page-Ladson archaeological site, a deep sinkhole under the river, researchers had to reach the riverbed 11 feet (3.4 meters) below the surface of the water, then dig another 15 feet (4.6 meters) into the sediment and soil. Using lasers to keep dig levels even and bright lights to operate in near total darkness, the archaeologists found proof supporting theories around the earliest people to live on the American continents.

A partially reassembled mastodon tusk recovered from the Page-Ladson site.
DC Fisher/Univeristy of Michigan Museum of Paleontology

Beneath the Aucilla's flow toward the Gulf of Mexico, they uncovered the bones of mastodons and other extinct megafauna alongside stone knives and tools. According to the findings, published online today in the journal Science Advances, these treasures show that 14,550 years ago, human hunter-gatherers butchered or scavenged a mastodon next to a small pond.

The researchers used radiocarbon dating on 71 different artifacts to determine the age of the items and their surrounding site. They also reassessed some earlier findings from the dig that were retrieved in the late 1980s and early '90s. At almost 15 millennia, this unassuming spot on private property near Tallahassee, Florida, is now the oldest radiocarbon-dated archaeological site in the southeastern United States, and the oldest-known underwater site in all the Americas.

"The new discoveries at Page-Ladson show that people were living in the Gulf Coast area much earlier than believed," said dig co-leader Michael Waters, director of Texas A&M's Center for the Study of the First Americans, in a press release announcing the findings. "These people were well-adapted to this environment. The site is a slam-dunk pre-Clovis site with unequivocal artifacts, clear stratigraphy and thorough dating."

A schematic of the recent underwater dig in Florida.
Jessi Halligan

The term "Clovis people" refers to a broadly defined population of humans living across the American continents as long ago as 13,000 years, who flourished in the present-day U.S. between 9,200 and 8,700 B.C.E.

They were so-named for the tips of sophisticated hunting tools first found near Clovis, New Mexico. These hunting tools held a degree of technical advancement that disappeared when the Clovis people did, and indicated the people hunted in groups, using coordinated attacks on large animals. 

While it was once believed the Clovis people were the first inhabitants of North America, recent research has proved that humans' relationship with the Americas goes back further into the Paleolithic era. Artifacts discovered in an Oregon cave suggest humans arrived via the Siberian land bridge 20,000 years ago. Linguistic analyses of Native American languages suggest that humans may have first made North America their home anywhere from 12,000 to 50,000 years ago.

The recent discoveries also underscore the fact that many early archaeological sites in the Americas are currently under either fresh or saltwater due to changes in river flow and coastlines.

A stone cutting tool known as a biface found in 14,550-year old sediments.