The cave meanders two miles under northern Alabama, with passageways leading to mysterious so-called dark zones, sediment deposits, a waterfall, and deep pools. Ancient footprints are embedded in the farthest passage. The names of Civil War Union soldiers remain scribbled on a wall.
Alan Cressler leaned over because the ceiling was so low, on July 30, 1998, unclipped a lamp from his helmet and let the beam slide across the surface above him.
The artwork of a fellow human being who lived many centuries ago came into view: possibly a bird with a round head.
“Once I saw that, I was like, ‘OK,'” Mr Cressler, who now works for the United States Geological Survey, said in an interview this week. “It gives me chills today to talk about it. I just saw the immediate importance of it.”
With an archaeologist, an expert in 3D photography and others, Mr. cressler further explored the cave, known as the 19th Unnamed Cave, and its art over the years. This week they published their findings in the journal Antiquity. The study highlighted the role of 3D technology in uncovering art that was initially not visible to Mr. Cressler more than 20 years ago when he was pressed so close to the ceiling that he could not see the full array moving in all directions. above it radiated him.
Jan Simek, an archaeologist at the University of Tennessee and a co-author of the paper, said the cave art was one of the largest found in North America, deep in a complicated dark zone where natural light can’t reach.
Using radiocarbon dating and analysis of pottery shards, the researchers estimate the art dates to the Middle and Late Woodland periods, or between AD 500 and AD 1000, when farming, hunting and gathering gave way to food production and sedentary life in the region.
There are figures with human features, a coiled snake with a tail rattle and forked tongue, and a ten-foot snake that winds its way across the expanse. Some incorporate the features of the ceiling into their design, such as the snake appearing to emerge from a natural crevice.
Ghostly humanoid figures are decorated with regalia. Charred fragments of river reeds suggest that the artwork, finely incised in a mud veneer, could have been a team effort, with someone holding a torch while the artist, or artists, were at work.
The early artists most likely lay on sediment deposits when they made their mud carvings, either with fingers or delicate toothed tools.
“It’s very detailed,” said Dr. Simek. “It occupies an acre of surface at the ceiling. The symbols are in a single room, but the cave continues.”
Since cave art was first documented in North America in 1979, Dr. Simek and Mr. Cressler is studying what is known as cave art in the dark zone, exploring passageways inaccessible to natural light.
The cave, documented in Tennessee in 1979, contained mud drawings, 750 to 800 years old, depicting pre-Columbian Native American religious themes, the antiquity study said. Since then, 89 other pre-Columbian cave art sites have been identified in southeastern North America. The oldest is almost 7,000 years old, but most date from AD 800 to AD 1600
Some are on private property and those findings are being kept secret to keep the area free from vandals. Others are on public lands, including in Virginia, Tennessee, Kentucky, and Alabama. Some can only be reached by boat, as rivers have risen to entrances that were once accessible by land.
The use of 3D modeling in Alabama’s 19th Unnamed Cave “promises a new era of discovery of ancient cave art” because it reveals images that could not otherwise be perceived, the researchers said in their study.
The technique has been used elsewhere, such as creating a replica of the art in the Lascaux caves in France, but not so much in the search, as Dr. Simek said, “to see if there are things that we cannot see.”
The researchers used a technique called photogrammetry, in which a camera walks along a track and creates overlapping images that are then stitched together using software. It creates a seamless rendering that highlights even the most beautiful carvings in the mud, said Stephen Alvarez, a founder of the Ancient Art Archive and a co-author of the study. He was responsible for the 3D work in the 19th Unnamed Cave.
More than 16,000 overlapping photos produced the map of the cave’s known art.
“It’s like magic,” Mr. Alvarez said. “Here’s this thing that’s been invisible for over 1,000 years and that’s suddenly come to life. Even though the people have been removed, their stories are still there.”
The method is useful because the uneven features of a cave ceiling can cast shadows that obscure delicate lines in the art. Mr. Cressler said these features complicated his early attempts to document the work with a camera.
dr. Simek said the use of photogrammetry was even more intriguing because ancient artists lacked such technology or ability to see the big picture. Unlike rock art, which is in the open air, the artists in the cave room couldn’t step back and think about their work in progress from a distance.
“The creators of these images couldn’t see them in their entirety except in their minds,” he said. “That means they had an idea of what to draw and move while doing that.”
But what exactly the artists had in mind has eluded the researchers until now.
dr. Simek said the project’s work with Native American collaborators helped interpret the cave’s possible relationship to the supernatural.
Dustin Mater, a Chickasaw citizen and artist who works with Mr. Alvarez, said cave art themes and depictions were similar to those he had learned in stories from tribal elders, such as cave portals to the underworld and a winged humanoid figure armed with a mace.
“It’s almost speculative, but there are nuances today that are carried through in our traditions and in our stories,” said Mr. Mater, whose ancestry belonged to indigenous peoples forcibly removed from northwestern Alabama in the 1800s. “Living cultures take symbols and then breathe new life into them and give them meaning.”
