Authorities in Iowa announced that a human jawbone found last month belonged to a prehistoric person.
The Marshall County Sheriff’s Office said that on Aug. 11, conservation staff conducting a biological and wildlife survey found a possible human lower jawbone in the Iowa River.
Officials said the jawbone was intact, but it had deteriorated to the point that they believed it was several years old.
Investigators also found three other potential human bones in the area, the department said.
According to the news release, the county medical examiner was called in to collect the findings and sent them to the state’s medical examiner’s office for more testing.
On Sept. 21, the sheriff’s office said that examinations by the state’s medical examiner’s office revealed it belonged to a human.
It was then sent to the Office of the State Archaeologist at the University of Iowa for further examination, which later determined that it likely belonged to a prehistoric Native American man who was middle-aged to older, the press release said.
According to the department, the other three bones were determined to be nonhuman.
This isn’t the first time in recent years that a Midwestern river revealed long-buried ancient human remains.
Last year in September, amid a drought, kayakers in Minnesota found part of a human skull. It was later dated back 8,000 years, from North America’s Archaic period.
By Sarah Rogers, Scripps National.