A new look at some very old microscopic bone fragments may have led to a new determination on the age of the earthen mounds on LSU's campus that Gov. Huey Long once took steps to preserve.

LSU geology professor Brooks Ellwood, in an extraordinary but unsubstantiated claim, is theorizing that the bone fragments, which were scarred in a super-heated fire, suggest the mounds are perhaps the oldest man-made structures in the Western Hemisphere, and possibly the world.

Ellwood says the mounds could be twice as old as previously thought. Earlier research had concluded they were built 5,500 to 6,000 years ago. Ellwood now estimates they’re about 11,300 years old, based on the material he found inside them.

Scientists who had explored the mounds previously had found an ashy material, a revelation that eventually struck a chord with Ellwood.

He said he came up with an idea to test some of the mound's deep material after a bad dream woke him in the middle of the night and he recalled ashy material he had found during an excavation in Albania in 1990. He pulled out his slides with pictures of that trip and noted similarities between that site and the one just steps from his campus office.

Ellwood said researchers may have overlooked the ashy layer, thinking it unimportant. Should it have been tested thoroughly along with other material unearthed in the dig?

With recent samples under a microscope, Ellwood said, researchers found what appeared to be tiny remnants of bones that could only come from mammals. The bits were surrounded by high concentrations of reed and cane material.

Ellwood said because reed and cane burn too hot for cooking, the material may have been used by people for incineration — possibly in ceremonial rites that included cremation.

“They weren’t burning cooking fires,” Ellwood said. “The only logical thing that it could have been is for human beings.”

Ellwood’s suggestion would be a potentially huge finding. Other researchers say they'd need to evaluate what he found and put it through the rigor of a review from other experts.

"Given the extraordinary claims, I would need to see the evidence before stating whether I agreed with the findings or not," said David Anderson, an archaeologist at the University of Tennessee in Knoxville, who has studied ancient mounds.

The Louisiana Department of Culture, Recreation and Tourism declined to comment, echoing other researchers reached by The Advocate who say the findings need to withstand a peer review before they can be accepted.

If Ellwood’s calculations are correct, the age of the mounds would be three times that of the Egyptian pyramids and could lend important clues about human inhabitants throughout the Americas, not just in Louisiana.

"These are really important native American antiquities that are on our campus just by accident," Ellwood said. "This is unique to LSU almost beyond anything."

Little is known about the people who built the ancient edifices. Ellwood speculated they were descendants of Clovis people, the Paleo-American culture known to have used spear-like projectiles and hunted mastodon and other giant beasts of long ago.

To have withstood changes in climate and the test of time shows that whoever built the mounds understood engineering.

"They knew what they were doing," Ellwood said.

Humans are believed to have journeyed across the now-underwater land bridge connecting Asia to North America, with estimates of that exodus dating back around 15,000 years.

Testing the DNA on bones and remains is difficult because researchers need permission from native tribal leaders to do so. Such tests often conflict with religious beliefs, and there’s an added aversion tied to grave looting by European settlers. There have been disagreements among scientists and native communities in some states, as well as calls for stronger protections of ancestral remains.

Native American mounds have increasingly attracted the interest of researchers, Anderson said, but it wasn't until the past 30 or 40 years that archaeologists realized how old they were.

Many of them are scattered along or near the Mississippi River, with several in Louisiana. They include those found at the Poverty Point World Heritage Site in the northeastern part of the state and the Watson Brake site, south of Monroe, which is about 5,400 years old.

Tristram Kidder, an archaeologist and professor at Washington University in St. Louis, said mounds may have been used as religious pilgrimage sites, similar to Vatican City and Mecca, or sites for political centers, or potentially both.

That thought shows people likely gathered at these places under a shared identity and forged their understanding of the world around them.

What Kidder and other researchers find remarkable about sites like the LSU campus mounds and Poverty Point is that people at the time didn't have the benefit of agriculture, livestock or metal tools.

"It's an extraordinary accomplishment for native peoples who've historically been denied this kind of status of having religious sites," Kidder said.

Researchers at LSU have long tried to preserve the mounds from further deterioration, not only from the elements but from people. LSU moved from a site north of downtown Baton Rouge to its current campus in the 1920s.

Long circled the mounds on a map while helping plan a portion of LSU's campus, labeling the area as an "Indian Reservation," which Ellwood said likely protected them from being flattened.

The tradition of sliding down the mounds on cardboard slabs to celebrate a sporting win became so common, the university began to restrict access to the area on game days.

In the 1980s, a student was killed while sunbathing atop one of the mounds when someone drove a pickup truck over her. The school later installed vehicle barriers to keep drivers away.

The university is exploring options to further protect the mounds, such as planting grasses and wildflowers to shield them from the elements, as well as posting signs telling people to keep off them.

Planting greenery would eliminate the added damage of mowing the grass but would require someone to pull out trees before their roots damage the mound. Another suggestion includes building a giant greenhouse over them.

The latest findings may lead to more support for a plan to protect them.

"There have been groups who've tried to get LSU to do something for over 20 years," Ellwood said. "LSU now understands the antiquity of it."

Email Youssef Rddad at yrddad@theadvocate.com.