THE BIG DIG
In North Dakota, find fossils aplenty.
On a blisteringly hot June day in the North Dakota Badlands, there are very few signs of life outside of birds, snakes and wandering livestock. The landscape is tall, stark and punishing, with loose rocks to trip you and serrated cliffs to cut you when you fall. Conical peaks rise from the ground, each striated layer full of potential discovery.
This was once a land of savannas and plains, with rivers and lakes. Unrecognizable creatures — with disproportionate limbs, spikes, shells, horns, unfathomable teeth — roamed freely, feeding on the tall grass and, oftentimes, one another.
On this day last summer, I was perched precariously on a steep, uncomfortably jagged mountain ledge that poked sharply even through my kneepads, the flat head of my rock hammer poised over a sharp chisel. The harsh summer sun cast a shadow over my tools, which were anchored in a crevice only millimeters deep. I paused.
“How old did you say this is?” I asked.
“That? Around 34 million years,” Clint Boyd, a paleontologist who was with me, answered casually.
When I first said I was going to North Dakota, the reaction of family and friends was universal: “What’s there?” Images of vast, unobstructed spaces that blur into the horizon don’t typically spark a tourism frenzy. But that pristine, lonely landscape has allowed nature to preserve one of North Dakota’s greatest intrigues: its prehistoric residents.
Nearly the entire surface of the state is sedimentary rock, largely untouched by glaciation, making it perfect for fossil preservation. There are ancient bones everywhere in North Dakota.
In what is now called the Badlands, an area so named because nothing much grows there, rhinos once roamed. Lakes and rivers in what is now a bone-dry landscape once sustained a population of large land tortoises. Cinematic favorites like Triceratops, duck-billed dinosaurs and Tyrannosaurus rex traversed North Dakota.
The state and its fossils have a unique, constantly evolving relationship, thanks in part to modern-day discoveries made on public digs. Die-hard dinosaur fans return each year to assist paleontologists, but the public digs are not well-known outside the world of fossil enthusiasts.
The bones I was to excavate last June were hidden, except for 2 inches of a rib sticking out of the mountain. The thin, khaki-clad paleontologist assured me that rhinos were very common in this area and that I wouldn’t ruin anything beyond repair. I swung the hammer onto the head of the chisel, sending a huge crack through stone that had been impossible to chip with just a trowel. With a second hit at a 45-degree angle, a chunk flew off, and I could see the rhinoceros’ rib bone, which had settled millions of years ago into the landscape outside Dickinson, due west of Bismarck, the state capital.
A few peaks and valleys over, Becky Barnes, another paleontologist, clad in jeans and one of her many humorous dinosaur-theme T-shirts, bent over a fossilized tortoise shell, her long braid poking out beneath a tan, widebrimmed hat. She nicknamed the shell Bruce’s tortoise in her field notebook. Bruce was neither an early explorer nor a notable scientist. Bruce — like me — was just your typical volunteer on a dig in western North Dakota. He’d happened to chip into a mountain and found a stylemys (similar in appearance to an outsized Galápagos tortoise), which lived about the same time as my rhino.
In the Eocene Epoch, which lasted roughly from 55 million to 34 million years ago, this area looked similar to the African habitats where rhinos live. This landscape is anything but flat. Walking through the mountains required good balance and paying attention to each step. Only by cracking the surface of these inhospitable rocks could you begin to discover the curious world of wildlife that once roamed here.
The public digs happened organically, in a very North Dakota way. Whenever residents discovered bones on their property (which still happens often),
they would call the paleontologists from the state-funded Geological Survey, who drove out to assess the situation. Once there, they relied on local volunteers to help properly collect and transport the fossils to the lab in Bismarck.
Over time, this practice evolved into an open sign-up for volunteers to accompany the paleontologists on their annual fieldwork. The digs are hard work. It takes a dedicated, curious person to play paleontologist with the Geological Survey for a few days each summer and unearth creatures that no longer exist. Most of the excursions are free, except for a refundable deposit.
There are a number of dig sites, like the one outside Dickinson, where volunteers are guaranteed to uncover fossils. The three paleontologists whom I had met, Boyd, Barnes and Jeff Person, also discovered several small creatures they had never seen before at this site, mainly types of fish and oreodonts (“walking food,” as Barnes calls them, referring to their place on the food chain).
This year’s public digs have been scaled back to four from five in 2016, because of budget cuts. The Bismarck area dig ( July 24-28) is the only one that focuses exclusively on dinosaurs. At Pembina Gorge (Aug. 8-12), volunteers can dig up sea life from 80 million years ago, like giant squid and mosasaurs (marine reptiles). The Medora dig ( July 13-16), near Theodore Roosevelt National Park, uncovers swamp creatures from 55 million to 60 million years ago. The Dickinson dig ( June 26-30) has the youngest mammal fossils, at 30 million to 40 million years old. Volunteers can join for one day or stay the entire five days.
At 7:30 on the morning of the Dickinson dig, I met up with the paleontologists in the parking lot of the Heritage Center and State Museum in Bismarck, off a highway dotted with large chain stores and hotels. A group email had informed volunteers about what to wear (closed-toe shoes, long pants, a brimmed hat), what to bring (plenty of water), what not to bring (iPods and headphones) and what to watch for (rattlesnakes, prickly pear cactus). Our car convoy headed west on Interstate 94 following their truck, which stood out from the sea of other trucks on the highway thanks to its trailer hauling a black fat-wheeled utility task vehicle.
The landscape changed as soon as the sprawl of big-box chain stores and Bismarck highways disappeared in the rearview mirror. The nearly 100-mile drive dispelled any myth that North Dakota is flat. As I followed the convoy in my rental car, we passed rolling hills with emerald green grass, farmhouses dotting acres of fields and wild, rocky landscapes. Tall signs advertising the Medora Musical, a popular western cabaret show, and the Enchanted Highway, a scenic route dotted with large sculptures, punctuated a big sky with swift-moving clouds. The convoy — eight adults including a mother with an adolescent boy — turned off the highway and ventured into farmland, kicking up rocks and dust on unmarked roads before parking in a green field that slanted upward. We outfitted ourselves with picks, brushes, awls, trowels and collection vials.
We hiked 15 minutes through prairie pastures before arriving at our test site, a flat and dry former pond, where the paleontologists could observe our techniques as we scoured the ground inch by inch in search of tiny fossils, which initially appeared similar to rocks. The paleontologists held unabashedly nerdy debates over whether dinosaurs had feathers between effortless explanations of terminology and time periods for the beginners in the group. Their well of patience and enthusiasm seemed endless, examining countless pieces of rock the volunteers mistakenly presented as fossils.
A group of elk watched with interest from a far-off plateau as we crawled in a prairie field where cows grazed. For every dozen rocks that looked like bones, there was one legitimate fossil. Finding that first fossil is crucial, however, because after that everything clicks into place. Suddenly the array of tan rocks started to look more like shapes, small bones; people started to differentiate previously imperceptible changes in color and texture.
From there, we hiked and took turns