Skeleton unearthed near Nancy Guthrie search site believed to be up to 1,000 years old, expert says

TUCSON, Ariz. — The discovery of prehistoric human remains just miles from the suspected abduction of Nancy Guthrie has unearthed a grim reality of Arizona's Sonoran Desert, where an expert says a dozen or more bodies can surface in a given year, and "there's just so much space" to conceal them.

Guthrie is the 84-year-old mother of "Today" co-host Savannah Guthrie, and as a result of her daughter's high profile, the grim discovery quickly caught national attention.

Just as quickly, experts determined the remains had nothing to do with her case.

In an interview with Fox News Digital, James T. Watson, an anthropologist at the University of Arizona who responded to the scene where the remains were found, revealed that there was a skeleton unearthed at the scene, not just the single bone that initially went viral.

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They belonged to someone believed to have been buried between several hundred and 1,000 years ago, he said.

"Whether it is a thousand years old or 50 years old, these are human remains," Watson said, adding that he hopes additional discoveries are treated with dignity and respect if searches continue in the Guthrie case.

A local YouTuber named AJ Wysopal came across an exposed bone while conducting an amateur search for Guthrie less than 5 miles from her home in the Catalina Foothills on May 7. Guthrie is believed to have been kidnapped out of her house in the early hours of Feb. 1.

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Authorities quickly determined that the remains were human — and also that they were significantly older and unconnected to Guthrie's suspected abduction. They are called prehistoric because they belong to someone who died before there was written language in the area, Watson said.

There is also a known archaeological site nearby, and Watson said that ceramic artifacts uncovered at the scene are consistent with known examples there.

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"All of that contextual evidence allowed me to be pretty sure that this individual was in fact Native American," he said. "The ceramics really sort of drove home that point."

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The remains have since been transferred to the Tohono O'odham Nation, a Native American tribe with a large reservation just west of Tucson. No additional research or testing is expected, he said.

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Watson said that a combination of the Sonoran Desert's harsh terrain and new developments on land that has been largely untouched for centuries often lead to similar discoveries as the search for Guthrie continues.

"The desert there is a pretty harsh environment and obviously it's been settled for hundreds, thousands of years," he told Fox News Digital.

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And in addition to inadvertent archaeological discoveries, the region is also near the U.S.-Mexico border, where illegal immigrants have for years been attempting to cross illegally in those same harsh conditions.

On some occasions, he's been called to the findings of their remains, he said.

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"There are literally probably hundreds of bodies that are discovered every year out in the desert," he told Fox News Digital.

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Like the recent find at River and Craycroft Roads, some are exposed by natural causes, including erosion caused by the region's powerful ephemeral rivers, which are mostly dry but flood violently during heavy rainfall in the desert. Others have been unearthed by real estate development, Watson said.

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And there could be many different reasons why they came to rest where they are found.

"So there [are] a lot of places that an individual could get lost or pass away — or hide a body," Watson said. "I think...as people start to poke into some of these crevices that don't normally get poked into into across the desert, they're likely to find more individuals."

The investigation into Guthrie's disappearance is ongoing, and there is a combined reward of more than $1.2 million in play.

Her family is urging anyone with information to dial 1-800-CALL-FBI. Tips can be submitted anonymously to Tucson's 88-Crime hotline at 520-882-7463.