Last Thursday, authorities in Iowa revealed that a human jawbone discovered last month belonged to a prehistoric individual.

According to the Marshall County Sheriff's Office, on August 11, conservationists working on a biological and wildlife survey discovered what might have been a lower jawbone from a human in the Iowa River.

The jawbone was still there, according to officials, but it had degenerated to the point where they thought it had been there for a while.

According to the agency, investigators also discovered three additional probable human remains nearby.

The county medical examiner was reportedly contacted to gather the results and send them to the state medical examiner's office for additional testing.

According to the sheriff's office, the state's medical examiner's office examinations on Wednesday showed the object belonged to a human.

It was subsequently sent to the Office of the State Archaeologist at the University of Iowa for additional investigation, and the results revealed that it most likely belonged to a middle-aged to older prehistoric Native American man, according to the news release.

The remaining three bones were found to be inhuman, according to the department.

This is not the first time this year that artifacts buried deep underwater have been found due to lowering water levels.

On Lake Mead, many human remains as well as a boat from World War II have been discovered since May.

Wildlife officials in Texas were able to discover 113 million-year-old dinosaur tracks in a dried-up river last month thanks to a lack of precipitation.