Since construction workers discovered prehistoric mammoth bones under the end zone of Oregon State University’s football stadium last week, thousands of extinct animal bones and fragments have been excavated.
But one last pile of dirt is still being explored by university students in an extraordinary on-campus assignment.
On Friday, dozens of students picked through piles of mud and clay, pulling out fragments of pelvis and rib bones left behind in the initial excavation effort. They placed them in 5-gallon buckets and soaked them in water to prevent deterioration.
“These ones here are all coming out of the same place, so this is all rib,” said Dave Ellingson, pointing out one bucket. “The bones are so fragile and they’re broken into so many pieces. It’s going to be difficult to put everything together.”
The Woodburn High School teacher has done this before, after bones from the same era were discovered on his school’s campus. Mammoths are Ice Age relatives of elephants that went extinct at least 10,000 years ago. That means their bones are, by definition, very old and delicate.
“It’s really like a piece of wet wood almost that just crumbles when you touch it,” Ellingson said. “That’s part of the problem we’re having with it.”
For the students here, digging up ancient bone fragments – even tiny ones – is a pretty fantastic classroom assignment. Undergrad Annie-Rose Eaton is an anthropology major, but she hasn’t done any excavating until now.
“The bones can tell you so much, and half the fun is looking for them, and getting really dirty,” she said. “It’s also really rewarding when you find a bone – even if it’s just an inch long. Still, you found it, and it’s really cool.”
But it’s hard work, she says. The soft pieces of bone break apart almost as easily as the surrounding clay and dirt.
“Right now I’m just trying to find them and make sure I don’t break any of them,” she said. “I don’t know the anatomy of a mammoth so I wouldn’t be able to identify one bone from the next.”
Anthropology professor Loren Davis said the mammoth discovery is the perfect opportunity to teach his students how to identify extinct animal bones.
“These are the kinds of experiences that are just going to cement their understanding of these lessons,” he said. “They’re never going to forget them.”
Based on the bones they’ve recovered so far, Davis estimates the mammoth was a juvenile – about 15 feet tall. He’s also identified bison bones and some kind of camel or horse. He plans to have his students help piece some of the bone fragments together to learn more.
“It’s one of the largest jigsaw puzzles I will ever work on in my life to try to piece these things back together,” he said.
Radiocarbon dating will tell researchers exactly how old the bones are. Soil samples will answer questions about what the climate was like at the time, what plants grew in the area and how much rainfall there was back then.
“What’s wonderful about working on these types of deposits is that we can learn things that you can’t know otherwise,” he said. “You can’t take a time machine and go back and see the animals and plants that were once here in Oregon. This is our time machine.”
OSU graduate student Sarah Skinner is studying the tools of the earliest humans. She says even though the mammoth discovery hasn’t unearthed any human artifacts, she’s still excited to learn from it.
“We’re digging up these Pleistocene megafauna that have gone extinct and early humans were living at the same time as these mammals,” she said. “Knowing more about the environment that this mammoth lived in, you can know a lot about the earliest peoples and what environment they were dealing with during this time when these large megafauna creatures were walking around.”
Somehow, Skinner says, humans adapted and survived while mammoths died off. She wants to piece together as much of that history as she can using what little remains from that era. This discovery, she says, just opened up a rare opportunity to gather new information.
“When the glaciers were going away, the environment was changing drastically. That’s one reason these megafauna were dying off,” she said. “Knowing anything you can about the environment at that time is really essential to understanding how these people adapted, what food they had access to and how they interacted with the species around them.”