Courier Staff Writer
As more and more bones are being uncovered at the mammoth dig site near Oskaloosa, an Ottumwa native is helping to reveal their past.
Sarah Horgen, education and outreach coordinator for the University of Iowa Museum of Natural History, is a 1998 Ottumwa High School and a 2002 University of Iowa grad.
After earning her degree in anthropology, Horgen went on to work at the office of the state archaeologist.
“I had always had an interest growing up in anthropology and natural history in general,” Horgen said. “I didn’t know it was a possible career until I got to college and somewhat accidentally took a class. I realized I could do that as a job.”
Today, Horgen is in charge of the education and outreach programs at the museum, and oversees tours and programs inside the museum, as well as coordinating field trips and presentations across the state.
“I’m lucky to have been able to have that career since I graduated,” she said. “It’s not the most common career.”
When an Oskaloosa farmer discovered the first four-foot femur eroding out of a creek bank after a massive rain two years ago, he brought it to the attention of the museum. When more bones were discovered this spring, he asked if the museum would be interested in excavating the rest since they were under a significant amount of dirt.
“Even though this landowner wishes to retain the bones, he’s allowing us to bring the public out to the site and view the excavation as an educational project and also to conduct research on the bones and different sediments around the bones,” Horgen said. “This mammoth project has kind of turned into an outreach event for the museum because it’s a way we can get the public involved with a unique project like this in a hands-on way, rather than going out to present on what we’re finding.”
The project will also unveil information about what Iowa looked like at the end of the last Ice Age, Horgen said.
“We know we have two animals at the site,” she said. “We’re still trying to determine their relationship to each other and their age. Both appear to be mature adult specimen based on the bones.”
In the last few weeks, a skull, complete with teeth and tusks, was uncovered.
“These two are some of the most important parts of an animal for research,” Horgen said, as they can lead to when the animal lived, died and environmental factors in play when the animal was alive.
These could be as old as 100,000 years old because mammoths lived in Iowa for such a long time, Horgen said, until they went extinct 12,000 years ago.
“Based on early evidence, we think these are from the end of the last Ice Age, around 12,000 years ago,” she said.
Horgen has participated in digs across Iowa and the Midwest, as well as in Verberie, France, a village about an hour north of Paris.
Her other digs have been mostly archaeological excavations, she said.
“At this point, there is no evidence of people at this site,” Horgen said. “It’s purely a paleontological dig.”
Most of the sites she’s worked on include evidence of early Native Americans in the state.
“But it’s possible at this site that we may find evidence of humans because Native Americans did come into Iowa before the end of the last Ice Age, and they hunted mammoths,” she said.
Horgen thanked Titan Machinery in Oskaloosa for loaning them a backhoe, a key piece of the project.
The main deposit is about 6-8 feet below modern ground surface, Horgen said, and while excavators have removed a lot of dirt, there’s still a lot more to move.
That means the end date keeps being pushed further out since the last bones discovered were buried deeper, Horgen said. It will be extended through the fall, “but beyond that I really have no idea.”