13,600-year-old Mastodon skull excavated from Iowa creek in ‘goldmine’ discovery after 12-day excavation

Tusk me, this is a big deal.

Archeologists unearthed an ancient mastodon skull from an Iowa creek this month — marking the first ever discovered in the state.

It took 12 days for excavators to slowly recover the massive fossil, which was so well preserved that it still had a significant section of its once-curved tusk.

“This is the first-ever well-preserved mastodon (primarily the skull) that has been excavated in Iowa,” said the state Office of the State Archaeologist.

Radiocarbon dating shows that the mastodon died in the Paleoindian period — and had been buried undetected for 13,600 years.

Mastodons — a 6-ton distant cousin to modern-day elephants — went extinct in North America around 10,500 years ago, likely due to climate change and hunting.

Though other remains of the mastodon were recovered, the skull was the most well-preserved piece of the skeleton, with archeologists calling the 2-foot section of tusk a “goldmine.”

“Apparently there are techniques now to determine how many calves a female mastodon had that get recorded as a chemical signature because of the changes in the body chemistry during the pregnancy and the birth. And that gets recorded in the tusks,” State Archeologist John Doershuk told Iowa Public Radio.

Scientists also hope that the remains can help answer burning questions about human history as well, including how involved our ancestors were in the mastodon’s demise.

The age of the fossil lines up with the time Native Americans would have migrated into south-central Iowa.

“The last glaciation probably still had the northern part of Iowa under ice. But the southern part was ice-free at the time and was starting to vegetate. Animals like mastodons were coming in to browse and human hunters would have also found that a hospitable place, as well,” Doershuk said.

The OSA did not find any stone tools near the bones, but scientists will analyze whether any human-made cut marks were left on the skeleton.

Although the bones were only excavated this month, the eroding site was brought to the OSA’s attention in 2022.

Once the mastodon bones are thoroughly studied and analyzed, the bones will become part of a new exhibit at the nearby Prairie Trails Museum.

Wayne County is located along Iowa’s southern border with Missouri and is 80 miles south of Des Moines.