Bone hunt: a reporter's week in the wilds of Montana

Science News,  August 26, 2006  by Sid Perkins

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"I think I've found something!" The call rang out from across the quarry. Suddenly, a dozen or so would-be paleontologists--myself included--shifted their mental focus from the small zones of rock immediately in front of them to a new center of attention. Having spent the last few hours using hand tools to grub our way through crumbly rock with little tangible result, we found the idea that someone had actually found something to be exciting indeed.

Nate Murphy, the paleontologist in charge of the dig, strolled over to take a look. "That's something, all right," he said. A little more excavation revealed the 3-centimeter-long tip of a theropod dinosaur's tooth. Considering the age of the rocks that entombed it, Murphy estimated that the meat eater had shed the fragment around 150 million years ago.

This episode, the first thrill on my recent foray into paleontology fieldwork, was by no means the last. Sure, most of those thrills were vicarious. Other folks found many more fossils--and more impressive ones--than I did. Nevertheless, I gained an understanding invaluable to my writing about paleontology--how dinosaur bones start their journey from rock formations into museums.

My invitation from Murphy, research director of the Judith River Dinosaur Institute in Malta, Mont., came late last year. "Have you ever been on a dinosaur dig?" he suddenly asked during a chat at October's annual meeting of the Society of Vertebrate Paleontology. "You need to understand what goes on in the field."

As I'd already suspected, extracting fossils from their stony tombs is hard, gritty work. The first step often is literally stumbling across bones that have eroded from a hillside. Then, there's some detective work tracking those fragments uphill to their source.

There's the backbreaking work of moving tons of rock to expose layers that hold the ancient bones, followed by the painstaking excavation of sometimes fragile remains that haven't seen the light of day for millions of years.

Most of the time, it's achingly monotonous. But oh, those moments of excitement!

SUNDAY, JULY 2: Members of the dig team gather at noon at a hotel in Billings, Mont. Many stayed elsewhere the night before--some at hotels, others at campsites, a few at their nearby homes.

Our 11-vehicle caravan reaches the dig site, about 160 kilometers north of Billings, in a little more than 2 hours. The highways and gravel roads that we follow pass through a variety of landscapes, including ranchland dotted with small oil wells and sparse forests.

We pull into our campsite and pile out of the cars into rolling pastureland. All eyes are immediately drawn to a grim, gray scar on the other side of a small valley, a quarry where Murphy and other paleontologists have, on and off during the past couple of years, spent time unearthing the remains of two large dinosaurs. We are tempted to rush over there, but there is a campsite to set up.

Dave Hein, owner of the ranch, has mowed an area where we can pitch the cook tent and park the supply trailers. Portable toilets are towed to the far side of the campsite, and the camp showers are assembled next to the water truck--compared with digs in more-remote locations, this expedition will be posh, I am told. I will be privileged enough to sleep in the back of a truck.

While the other campers set up their tents, I chat with Hein to find out more about the site. Some of his wife's ancestors--five brothers from England, from whom Hein's 5E Ranch gets its name--settled here about a century ago. In 1985, Hein first found chips of fossilized bone lying on a hillside.

Then in 2003, he and his son used some earthmoving equipment at the site and came across a few large bones. Realizing the possible importance of the find, they turned to local experts. After a series of phone calls, Hein spoke to Murphy, who has since excavated bones at the site each summer.

Around the campfire after dinner, at Murphy's behest, we take turns introducing ourselves. Our group of 33 includes teenagers, retirees, museum volunteers, geologists, paleontologists, and even a theology professor. Only about half of us have been on digs before, and we are all itching to get our hands dirty.

We spend the rest of the evening in song, 2 hours of guitar- and coyote-accompanied ballads, folk tunes, and sing-along classics such as "Dead Skunk in the Middle of the Road."

Long after we stumble off to our sleeping bags, the coyotes are still singing.

MONDAY, JULY 3: We gather at the site to learn some basic digging skills. The standard-issue tools are awls--think ice picks on steroids--and stiff paintbrushes. We aren't to use the awls like ice picks, however--a motion that Murphy refers to as "Hitchcocking."

Instead, we are to gently pry apart layers of rock, brushing away the debris and inspecting our work zone regularly so that we won't damage any fossil before we realize it's there. Done right, it's slow going. Poke, pry, sweep, repeat. Fill up a gallon-size scoop with debris, and then dump it in a bucket. Six or eight scoops fill a bucket, and six or eight buckets fill a wheelbarrow. Roll the wheelbarrow downhill, empty it, return to your little section of strata. Fill, roll, empty, repeat. A ton of rock makes a pile much smaller than you'd think.