by Lisa Bickell
This June, I went on a dinosaur hunt. More accurately, I worked with our partner in the US Forest Service to take 14 teachers to the Rocky Mountain Front to learn about the area’s geologic history. But really, we were all looking for dinosaurs.
The experience was part of our Forest for Every Classroom program. Over six years, with partners including the US Forest Service, Montana Fish Wildlife and Parks, Montana Discovery Foundation, Montana DNRC, and a whole host of other non profits, over 100 teachers have graduated from the intensive program that focuses on teaching curriculum standards through place-based learning. Our commitment also includes ongoing educational opportunities for our alumni teachers. So, in June, we welcomed 14 teachers from all over western Montana to explore the geology and paleontology along the east side of the Rocky Mountains near Choteau, MT.
I know that Montana has a rich, and well preserved, geologic history, with fossils to find from more than one era. But I did not expect them to be, well, everywhere.
For our two-day field experience, we joined the Two Medicine Dinosaur Center in Bynum, MT. Their staff, paleontologists, and educators, are incredibly knowledgeable and they are great at giving us non-paleontologists opportunities to join them in real field work. To get us started, they took us to a private ranch where they have a few dig sites, and let us out on a gravel road. Our mission was to find dinosaur bones. After learning some of the basics of what to look for, we wandered down the two lanes of crushed rock picking up anything yellowish, brownish, reddish, or sky blue. The trick? Real fossilized dino bones will stick to a wet finger (or tongue) like it is suctioned on there. That’s because the fossilized bones, still having the network of holes inside, will pull the moisture right in. So there we were, walking and licking rocks.
On the roadbed, any bones at the surface have been crushed, so we were able to find small pieces here and there. And this site was loaded with duckbill dinosaurs, or hadrosaurids. They can’t know for sure what species, but they do know that they are from the Cretaceous Period.
The region we were exploring, down from the Rocky Mountain Front near the Pine Butte Swamp Preserve, is part of the Two Medicine Formation which extends through Montana into Alberta. The geologic formation, mostly sandstone deposited by rivers, is 70 to over 80 million years old. A bit south of our road is Egg Mountain, the site of the world’s first dinosaur embryo discovery. They were Maiasaura nests. Due to the region’s concentration of dinosaurs once living along an ancient inland seaway, this area is a hotbed of fossil discoveries. When it rains, dinosaur bones are exposed on the arid, open land.
After most of us felt like we could differentiate between a fossil and a rock, we moved to a different site where we’d be able to look for larger fossil remains.
Our next stop was on the same ranch but in a less disturbed area. Here we were challenged to test our new knowledge and find more fossil evidence. Feeling a bit overconfident, perhaps, we all walked right by a two-foot piece of leg bone lying sideways in the grasses and prairie flowers. See it in the photo? Yep, kind of looks like a basic rock. But that’s part of a tibia!
As we wandered through the field, our paleontology guides pointed out vertebrae, pieces of ankle joints, more leg bone fragments, and other smaller and indistinguishable parts. And truthfully, they seemed to be scattered everywhere we looked–now that we were better able to identify them. Most of the fossils we found are from the hadrosaurids, called the “cows of the Cretaceous” due to their numbers in this area. For isolated pieces like this, it is hard to know exactly which species of hadrosaur you are looking at. In Montana, we have records of Anatotitan (Anatosaurus), Tenontosaurus, Edmontosaurus, and Maiasaura. Paleontologists can accurately identify them to species if they are given more clues.
Later that day we visited a disturbed hadrosaur nest site and were asked to find the egg shell pieces. Once we started looking, they were everywhere. Looking into our shadows, we could see hundreds of tiny black flecks among a field of white rock. Looking closely at the shell pieces, you could see various textures, smooth, wavy or ridged, and stippled. Each of these different textures indicates a different species of dinosaur: wavy, ridged patterns belong to hadrosaurs, smooth belongs to troodons, and stipples (raised dots) belong to an as-yet-unidentified dinosaur (no intact eggs with identifiable embryos inside have yet been found). It was wild, standing on a nest site, imagining what the landscape looked like tens of millions of years ago.
Over the two days we had an opportunity to work at an active dig site, another hadrosaur. Back in the museum’s laboratory, we did a little work on a Triceratops encased in a plaster field jacket. When paleontologists find large fossils that are too hard to remove and safely transport from the field to the lab, they can encase them in plaster for transport. Then they can stay stored in the lab until there is time (or 14 enthusiastic teachers) to work on clearing the fossils out. Both times we had to work slowly, carefully, and with little more than a dental pick. But how amazing it was to be picking at the dirt, looking for real dinosaur bones!
Montana has a pretty exciting fossil record. You can travel around the state and find dinosaurs of the Mesozoic Era, like we did. But you can also go farther back in time and find fossilized cyanobacteria (stromatolites) from the Precambrian Era, which spans from the formation of Earth to about 541 million years ago. And then you can jump forward and find Pleistocene Epoch fossils of prehistoric bison, camels (yes, camels!), and woolly mammoths. Travel the Montana Dinosaur Trail and you’ll visit museums and other education centers that will showcase the rich diversity of fossils found in our state.
On our last day, we took a small trek up a tall, narrow hill to look for more fossils. And embedded in a rock we found imprints from prehistoric mussels and a crocodile tooth! Can you find them in this picture?
Taking teachers out into the field is pretty fun. It’s exciting to hear about what they are teaching in their classrooms. I love hearing their stories and thinking about what I can do to support their work. But it was something altogether magical to wander together, all as students, through fields of dinosaur bones.
Special thanks to the Two Medicine Dinosaur Center for a fantastic field experience and to The Nature Conservancy for hosting us at their Pine Butte Ranch. And to the teachers.