How To Find Dinosaur Bones

Though I travel far and wide, it is rare that I get to travel so far back in time (to the Cretaceous period) and walk among the gigantic wildlife (dinosaurs) who once romped along the tropical shores of central Montana. Admittedly, I was once a young boy with a bedroom full of plastic dinosaurs and an obsession with beasts for which there was no zoo, and  traveling to Montana turned me back into that very same kid, giddy with the thrill of hunting down any vague remnant of the prehistoric past.

Now, finding dinosaur bones is hard work, and not as simple or quick as the movies might indicate, but just an hour after heading out from the  Two Medicine Dinosaur Center, I had already spotted and correctly identified my first real dinosaur bone fragment. I spent the rest of the day digging in the dirt, imagining the Hadrosaurid and Ceratopsian melee that took place on this very spot.

One day on a dig does not a paleontologist make, but in the time I spent searching for dinosaurs, I sure learned a lot—like how I lack the patience it takes to be a paleontologist but how awesome it would be. I also learned the seven fundamental steps behind finding dinosaur bones:

1. Come to Montana More dinosaur bones have been discovered in Montana than in any other state in America, which explains why Montana’s Museum of the Rockies holds the largest collection of dinosaur bones in the world. While visiting Montana doesn’t guarantee you’ll find dinosaur bones, it offers plenty of opportunities to try. and the Two Medicine and the Montana Dinosaur Trail

2. Find A Wash

“What you’re really looking for is a conical bluff or badlands with scarping,” advises Matthew Haacker, a geologist at the Two Medicine Dinosaur Center. Any signs of erosion—like a wash that flows out, “You definitely want to look there.”

A long, long time ago (80 million years, give or take), most of Montana was underwater, forming part of the great Western Interior Seaway. The Rocky Mountains were also about twice as high as they are now, eroding away into the sea. That means the part of Montana where the mountains meet the plains was once a prehistoric beach, with so many rivers running into the sea, which deposited heavy sedimentation—ideal conditions for fossilizing dinosaur bones.

Today’s erosion continues to expose and release long-hidden dinosaur bones, sometimes to the point of pushing them right out on the soil surface.

3. Search for Something Different

Why do paleontologists take tourists like me out into the field? “Because you have fresh eyes—and the more eyes looking, the better,” explains Matthew. When “walking” a site, search over the stones on the surface—what sticks out? What looks a little out of place? Notice shape, color and pattern.

“Look for something different on the ground, and when you inspect it, look for patterns,” adds Matthew. Dinosaur bones will usually show a lined organic pattern, which are the fossilized Haversian canals from the original bone tissue.

4. Brush It Off

Use a paintbrush to dust off your specimen and inspect it closely. Do they look like bones—and more importantly, do the lines end in holes? Straight lines that end in holes are evidence of bones, revealing the fossilized Haversian canals.

Lines that wrap all the way around a rock indicate that it’s a rock—these are layers. If the lines on one edge are perpendicular to the lines on the adjacent surface—this is merely a mineral. Fractured stones have lines that go in many directions.

5. Stick Test

Once you think you’ve got dinosaur bones, do the stick test. Lick one of the ends with holes, wetting it with saliva, then press it into your finger, hold it firm, and count to ten. Bona fide dinosaur bones will stick to your finger so that even if you shake your hand, the bone will stay stuck.

The stick test works from capillary action in the hollow tubes of the dinosaur bone, causing suction. Dry bones stick better than wet ones, and small bones work better than big ones, whose canals often get filled in with sediment.

6. Float Mapping

Congratulations—you’ve found dinosaur bone fragments! Now you have to find out where they come from. Paleontologists call these small bone fragments “float” and they map the float to determine the most likely source and where to dig.

Float mapping is a study in erosion and taphonomy (decay). In Montana, many of these bone fragments tumble down from exposed vertical layers, while wintertime freezing (which breaks bones apart) will “erupt” bones out of a hillside. Once you’ve followed the float to the source, you can begin your dig.

7. Dig

“You want to see what goes into the hillside,” advises Matthew. “You want to find bones in situ.” That means digging slowly and softly, removing the layers of earth carefully. Digging is done with a variety of tools, from small brushes and ice picks to giant pickaxes and even mechanical backhoes. Still, paleontologists are meticulous, cautiously removing dirt and stone, recording everything that transpires.

Paleontologists might spend more time documenting a dig than they spend actually digging. In Montana, they mark a datum point and use GPS to record the exact locations of each find, no matter how small. Once they find bone, they work gently around it, knowing that it might be connected to other bones, or perhaps (if they are lucky) a whole skeleton.

Paleontologists are detectives, working every day to solve a mystery. Digging is part of that detective work and it’s amazing fun.

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On my dinosaur dig, I spent most of the afternoon chiseling away at grey sandstone, slowly removing the sediments around a very large dinosaur bone, crumbling away the non-essential dirt but always conscious that there might be something bigger and better in there.

Sure enough, we found another hard surface and discovered a much larger bone hidden beneath the sandstone. Pulling away the rock and exposing a sizable dinosaur bone, an animal that’s been hidden from view for some 72 million years, was probably the most exciting thing that’s ever happened to me on a field trip. Suddenly I understood the compulsion of paleontologists and all the millions of children that are in love with dinosaurs. Digging up dinosaurs is awesome, and I didn’t want to stop. When the day was over, I didn’t want to leave because I wanted to keep digging and find out exactly what was down there.

So I guess that means I am addicted—to dinosaur bones.

Visitors to Two Medicine Dinosaur Center in Bynum, Montana can participate in 3-hour, full-day, or longer-term dig programs, which can cater to serious paleontology students or for children and families.