The ever-rising tide of history can obscure many things, but one thing archaeologists may not have expected to be hidden was a 7,000-year-old Native American burial site.
The site, located a mere 900 feet (275 meters) off the coast of Manasota Key in Florida is preserved in what would have been a "a peat-bottomed freshwater pond thousands of years ago," according to a statement released by the Florida Department of State.
"This will forever change the way we approach offshore archaeology. As we continue to learn as much as possible from the site, we look forward to sharing that knowledge with the people of Florida," Ryan Duggins, the underwater archaeology supervisor for the state's Bureau of Archaeological Research, said in the statement.
Reports of the site began in 2016 after divers noticed what appeared to be some sort of human remains on the seafloor, at a depth of only 21 feet (6.5 meters). A diver eventually collected what turned out to be a human jawbone.
The diver notified Duggins by sending a photo of the specimen. It was immediately cause for excitement thanks to a lone, well-worn tooth in the jawbone. The tooth was smooth molar, and its smoothness indicated that it likely belonged someone used to eating tough foods.
"That's something we don't see in modern populations, so that was a quick indicator we were dealing with a prehistoric individual," Duggins told National Geographic.
Duggins and other underwater archaeologists went diving and discovered a trove of remains: broken arm bones, pieces of skull, wooden stakes and textile fragments. The stakes and skulls indicated to Duggins that they were likely looking a surprisingly well-preserved Native American bog burial site.
In 2017, Duggins and the team returned to the site to excavate a small area of land to see what was hiding underneath the seabed's peat. More organic remains were discovered, along with more stakes and textiles. The researchers have unearthed six individual sets of human remains, but they expect to find a lot more since the evidence suggests the graveyard might stretch out over an acre.
Radiocarbon dating sets the remains at around 7,000 years old. At that time, the hunter-gatherers in the area were starting to transition to more permanent villages, hence the burials in this ancient pond. Over the centuries, rising sea levels swallowed the coastal area, claiming it for the sea.
"What we currently are thinking is that when an individual passed, they would have been wrapped in handwoven fibers and sunk to the bottom of the pond," he explained to National Geographic. "A series of fire-hardened and sharpened stakes would be pounded into the pond bed around the body with the tops of those stakes protruding above the water line."
More work is obviously needed given the potential scope of the site, and Duggins is aware of the importance of the find.
"Seeing a 7,000-year-old site that is so well preserved in the Gulf of Mexico is awe-inspiring," he said in the Department of State press release. "We are truly humbled by this experience. It is important to remember that this is a burial site and must be treated with the utmost respect."