ROM paleontologist David Evans on a dino dig in southern Alberta.
The ROM's dinosaur-hunter, deep in Alberta's badlands
ROM curator David Evans is an Indiana Jones-like figure, spending his time hunting dinosaur bones and battling rattlesnakes in his relentless quest to further science.
By Kate AllenStaff Reporter
Fri., Aug. 5, 2011timer10 min. read
ALBERTA, NEAR THE MONTANA BORDER—Tramping up a cactus-dotted hilltop in the badlands of southern Alberta, David Evans stops dead. "Hey, you guys want to see a velociraptor claw?" he asks.
As he bends down to pick up the fossil, an angry rattle fills the hot, dry air: rattlesnake. It's coming from the brush not a metre from his hand.
Evans leaps backwards. A few adrenalin-charged moments pass before the excitement drains out of his voice.
"A rattlesnake guarding a velociraptor claw," he jokes, shaking his head. "You can't write this stuff for a movie."
Actually, you can, and somebody has. That movie is called Indiana Jones, and its globetrotting professor-hero is an only slightly exaggerated portrait of a hotshot young dinosaur scientist.
Evans, 30, curator of vertebrate paleontology at the Royal Ontario Museum, travelled to Mongolia, Sudan, and Uruguay in the course of last year's work. He and his colleagues trade casual tales of encounters with polar bears, desert vipers and U.S. homeland security. Obstacles to their work include black-market bone smugglers and surly Canadian cowboys.
He can also spot an inch-long bone amid a pile of rocks, and know instantly that millions of years ago it belonged to a dromaeosaur, the feathered, sickle-clawed family of dinosaurs commonly referred to as raptors. Give him a piece of fossilized dinosaur frill, and he can say with certainty it's from a species unknown to science.
But unlike Indiana's fictional pursuits of arks and aliens, Evans' work carries real significance, and goes beyond filling the ROM with exhibit-worthy specimens. The research he is doing on dinosaur evolution in the period immediately before their extinction — a time of huge climate fluctuation — is more relevant than ever to the survival of the 21st century animal kingdom, homo sapiens included.
Evans was born in eastern Ontario, but grew up in Kelowna, B.C. He saw his first fossils at the ROM during family visits. He doesn't remember a specific moment when he decided to become a paleontologist. "That's just what I had to do. I never thought about it," he says.
When he was brought on to lead the vertebrate paleontology program in 2007, Evans, then 26, was the youngest curator ever hired by the ROM. He is also an assistant professor in Ecology and Evolutionary Biology at the University of Toronto.
"He's known as one of the new, upcoming movers and shakers in dinosaur paleontology," says Philip Currie, the Canada research chair in dinosaur paleobiology at University of Alberta and one of Evans' early mentors. "He's very smart."
Canada is fertile ground for an ambitious young paleontologist. During the mid- to late-Cretaceous era, between 90 and 66 million years ago, a shallow inland sea divided North America. Sediment-laden rivers that flowed into the sea created ideal conditions for transforming bones into fossils, and present-day Alberta sits atop those ancient waterways. The province has produced some 1,000 dinosaur skeletons in the last 100 years, Evans estimates, more than any other similarly sized part of the world.
Since 2005, Evans and a colleague, Michael Ryan of the Cleveland Museum of Natural History, have been leading dinosaur-digging expeditions to a remote pocket of Alberta 100 kilometres south of Medicine Hat, just shy of the Montana border. While the province boasts other dinosaur graveyards that are much easier to access, the team has chosen this site, and the punishing conditions that go along with it.
Every morning, Evans, Ryan, and their dozen crew members pack a bagged lunch, fill as many water bottles as they can carry, and climb into a convoy of all-wheel-drive pickup trucks. Access to the quarries, as dig locations are known, is a long, jolting drive from base camp across dirt roads and pitted tracks that peter out in an expanse of lonely prairie. (Gas costs and truck rentals are by far the fattest item in their approximately $30,000-per-year budget. That money comes from various grants provided by, among other institutions, the Natural Sciences and Engineering Research Council of Canada, the Dinosaur Research Institute, and the ROM.) From there, the researchers toss their supplies on their backs and hike down into the badlands.
Badlands are steeply eroded gullies carved into the land by centuries of wind and water, exposing successive geological layers along with the fossilized remains of animals that died in those epochs. The qualities that make these rock formations perfect for fossil-finding — millennia of stacked biological history, with little vegetation to obscure any bones that have eroded out — are precisely what make them difficult for fossil-digging. Alberta's dry summer heat radiates off the exposed rock-face, boosting daytime temperatures into the 40s and 50s, while wind whips dust into every exposed orifice. Mosquitoes and other flying pests swarm any warm-blooded being available.
Down in these canyons and coulees, it wouldn't be hard to mistake a dinosaur-digging crew for a chain gang. Researchers almost never stumble across a complete, fully connected skeleton lying on the ground, Jurrasic Park-style. Usually, they find an intriguing chunk of bone poking out of a hill, and must dig back into the incline if they want to see what else is hidden there.
This year, Evans is particularly excited about a bone bed they have just begun to expose which is almost certainly the remains of an individual ceratopsian — the family of frilled, horned dinosaurs that included triceratops — but seems to be a species no one has ever documented.
Each species of ceratopsian is set apart by its frill ornamentation and its brow horns, called post-orbitals. The team has found most of the animal's strange-looking frill, as well as various ribs, vertebrae, tail pieces and other remnants, but not the important post-orbital. They want those bones.
Still, Evans says with excitement, "It's looking really good for it being a brand new species."
The excavation process starts with jackhammers and pickaxes, used to remove the tonnes of unfossiliferous rock above where the bones lie. When the crew has worked down to about a metre above the bone bed, they switch to pocketknives and other small tools, chiselling away the crumbly stone that surrounds the bones. They use fat paintbrushes to sweep away dust.
For a field that attracts eggheads, the process is physically intensive. "I was under the impression that one got an advanced degree to avoid digging ditches," one student complained on a particularly parched dig day.
"You were wrong. Keep digging," Ryan responded.
Social skills are as crucial as physical stamina. Eight hours of crouching in quarries in the baking heat surrounded by mosquitoes can pass a lot quicker with companionable colleagues; conversation trends towards in-depth comparisons of Nirvana albums and ribbing of graduate students' nerdy hobbies.
Likewise, the researchers' base camp and some of the dig sites are located on private land, and Evans and Ryan work hard to maintain positive relationships with the local ranchers. While one landowner has barred paleontologists from his property and what could be several exciting bone beds, most are strong supporters. Ryan named an important discovery — Albertaceratops nesmoi — after Cecil Nesmo, a particularly enthusiastic advocate who lets researchers pitch their base camp on his land.
Then again, both the locals and the dig conditions could be a lot more difficult. In Mongolia, smugglers have pulverized important fossil beds to supply the booming black market in dinosaur bones. A Mongolian viper once chased Ryan after he got too close. And Evans had a close encounter in the Arctic with a polar bear that prowled within striking range of his team's base camp. (The run-in with U.S. homeland security came in Alberta, when Evans and some team members hiked too close to the Montana border; helicopters were on them within minutes, but flew off without incident.)
"You have to be able to roll with the punches," says Evans.
But as far as Albertan dig sites go, Evans and his team have chosen a particularly difficult, rarely visited locale. They have a strong scientific reason to do so. "If you're going to find answers to interesting questions about dinosaur evolution, you're going to come to this part of Alberta and sit out here in the hot sun," says Ryan.
A major unresolved question in paleontology is what wiped dinosaurs off the earth during the extinction event that punctuated the Cretaceous period. Almost as important is the question of dinosaur diversity leading up to that event. Were dinosaurs thriving until they were done in by a single catastrophe — most likely an asteroid?
Or was their genetic robustness already dwindling from any number of environmental pressures (such as climate change) and an asteroid was the final straw? If so, climate change could be one culprit. Paleontologists have discovered that the climate of the Cretaceous, after a long slow cooling, began to heat up. Temperatures peaked right before the extinction event, before suddenly cooling off. Paleontologists know a great deal about the last 10 million years of dinosaur life, right before the extinction, but not a lot about what the world looked like two to five million years before that. This is the time interval Evans and Ryan are digging into. As they find more specimens, they will get a better picture of whether the dinosaur community was indeed stressed, and whether climate change was a factor. Evans believes that dinosaurs were losing diversity, and that paleontology provides clues as to how modern-day lifeforms will react to climate change. It's not a happy picture, unsurprisingly. "Many species won't be able to cope," Evans says. "Paleontology tells us this."
For all Evans' big-picture objectives, building up the data set to get there requires loads of fossils, and that starts with field work. One evening at base camp, Wendy Sloboda, a crack fossil hunter who made world headlines at age 16 when she found a nest of embryonic dinosaurs, presented Evans with a chunk of bone she had found in an area of unexplored badlands.
Evans immediately snapped upright. "Woo hoo hoo!" he hollered.
Sloboda's discovery was a partial leptoceratopsid skull, a type of small, very rare ceratopsian for which paleontologists have only recovered a couple of teeth from this particular time interval. The new chunk of fossil was exciting enough to generate at least a research paper, and possibly even name a whole new species.
Evans turned the pieces over in his hands excitedly as Ryan and the rest of the crew clustered around.
Another day, another buried treasure unearthed — not the holy grail, but maybe something even more important.
"This is freaking awesome," he said.
Tracking dinosaur diversity
Of all the fossil-rich locales in Alberta, by far the most prolific is Dinosaur Provincial Park, a UNESCO world-heritage site that has drawn paleontologists in droves since the first fossil discovery there in 1884. Over 150 complete skeletons have been dug out of the 73-square kilometre park.
Far fewer paleontologists have visited the region 250 kilometres to the south, where Evans and Ryan are digging. "We're working in an area where it's hard to find fossils, but since we know almost nothing about it, everything we find is interesting," Evans explains.
The rock formations in Dinosaur Provincial Park were laid down 76 million years ago, in the late Cretaceous, 10 million years before dinosaurs went extinct. Because it's so easy to find fossils in the park, paleontologists know more about this period of dinosaurs than any other.
The dinosaurs that Evans is digging up, like the possibly new species of Ceratops, are from rocks two to five million years older than those in Dinosaur Provincial Park. Very little is known about these animals. For Evans, that's ideal. He's less interested in finding isolated skeletons to stock museum exhibits. He wants to know how these creatures lived, how they died, and what their evolutionary relationship is to the Dinosaur Provincial Park skeletons. "We're trying to decipher the diversity of dinosaurs through time, and how it's related to big events like climate change," says Evans.
Dinosaurs, as it turns out, experienced a series of major climate fluctuations. Around 66 million years ago, after a long period of cooling, temperatures began to rise, peaking around 100,000 years before the extinction of the dinosaurs, and then suddenly dipping back down.
Evans wants to know how the climate and dinosaur diversity are related, and whether it played a role in their extinction. "Is it just a bad day, and an asteroid falls out of the sky?" he wonders. Or did climate help weaken dinosaur diversity, leaving them susceptible to a catastrophic event? Paleontologists deeply disagree about the question of dinosaur diversity leading up to the extinction.
Though the team's research is ongoing, Evans can offer scientists of modern-day biology a few conclusions from the paleontological record. "You will lose a lot of biodiversity, almost certainly," he says. "I'm not sure what the world will look like, but I don't think we're going to like it very much."
Kate Allen