How to Build a Dinosaur (3 page)

TIME, SPACE, AND DIGGING TO THE PAST

“Scientific people,” proceeded the Time Traveler, after the pause required for the proper assimilation of this, “know very well that Time is only a kind of Space.”

—H. G. Wells,
The Time Machine

 

 

T
o get to Hell Creek, you drive east from Bozeman. And back in time.

Bozeman is firmly located in the present. Twenty-five years ago it was a sleepy college town, where you could stop into a video poker bar and play pool while the Montana State University rodeo team celebrated at a nearby table. The town had coffee shops and college burger joints and creeping vegetarianism, but styles still lagged behind the coasts.

Things have changed. In 1980 Bozeman had a little more than twenty thousand people. Now it has about thirty-eight thousand. The nearby Gallatin, Madison, and Yellowstone Rivers have drawn fly fishing tourists, the Paradise Valley has attracted Hollywood royalty, and the foothills of the Rockies have become dotted with vacation homes of Angelenos. Early settlers in this migration, like Peter Fonda and Ted Turner, seem almost like natives now. High fashion may belong to the East and West Coasts. But as for outdoor chic—what’s cool in mountain bikes, running shoes, and river sandals—Bozeman is at the forefront. It is not a city where you end up by chance. It is a destination.

You can’t blame the new Montanans for coming here. They are drawn by the rivers and the mountains, the big sky east of the Rockies, and the rich fir forests west of the Rockies. And the fishing.

From a paleontologist’s point of view the resulting change is something like deposition. Geological environments are of two sorts, depositional and erosional. At the extremes, a river delta deposits a lot of silt and builds up the land, while a mountain slope is constantly eroded by wind and rain. All of history is depositional, I suppose, in the sense that events accumulate, languages and cultures change, adding layer upon layer of human experience. In Bozeman the rate of cultural deposition is high, and increasing.

Espresso is now the drink of contemporary Montana. I’ll wager that it’s easier to get a triple skim latte around Bozeman than it is on the Upper West Side of Manhattan, at least if you don’t want to get out of your vehicle. We have drive-up espresso stands, where the pickups and the Priuses idle in line together. Latte is the cowboy coffee of the twenty-first century.

Bozeman is just east of the Rockies, in the foothills of the mountains. To the south lie the deep, fir-banked canyons of the Gallatin River and the bison and elk of Yellowstone National Park. To the west is farmland cut by the Madison River. In July the river is filled with small drift boats, skippered by fishing guides, often college-educated northeasterners who practice the religion and business of trout in Montana in the summer and Argentina in the winter.

To the northwest lies the Blackfeet Reservation and, beyond that, Glacier National Park with its Going-to-the-Sun Road that takes you over the Continental Divide. To the northeast lies the high line, the towns that dot the rail line just beneath the Canadian border, towns like Cut Bank, and Shelby, where I grew up.

All of these routes have their attractions, but for time travel I recommend driving due east. Take Route 90, a modern four-lane highway that parallels the Yellowstone River, which itself was a highway of sorts in earlier times. The twenty-first century keeps you in its grip for a good 150 miles until you leave the highway at Billings, the state’s largest city, with a population of close to one hundred thousand. Take Route 87 north, a flat, two-lane road through farm- and rangeland that leads to a crossroads marked by an enormous truck stop on the southeast corner. Look east down Route 200 to the heat-rippled horizon. That’s where the past lies.

The next town is Winnett. It is small, population less than two hundred, hidden from the road, and deep enough into the all-but-empty western end of the Great Plains that there are no familiar fast food chains. There are, however, satellite dishes everywhere. And on the way into town a few years ago you could see small roadside signs made as part of a high-school antidrug campaign—unhappy reminders of modern life on the wide-open, economically depressed High Plains. “Violets are Blue, Roses are Red, If You Try Meth, You’ll Be Dead.”

The gap between Bozeman’s prosperity and the economic situation of eastern Montana is significant. The state as a whole had more than 14 percent of the population under the poverty line in the 2000 census, which partly indicates the dire situation of the several large Indian reservations in the state. In Gallatin County, which includes Bozeman, the rate was 12.8 percent. In Garfield County, which does not include any reservation, it was 21.5 percent.

From Winnett east the road runs through open country for the next seventy-five miles. There are no towns. Other cars and trucks are few. The power lines are not always visible. The road runs straight to the horizon. Even traveling at eighty miles an hour, you can feel the distance and the emptiness. In a car with a tankful of gas it is exhilarating. On foot it can be oppressive. If the space seems endless now, what did it seem two hundred or one hundred years ago?

The road cuts through the Missouri Breaks, the same eroding badlands that Lewis and Clark passed through, that Sitting Bull knew, that were here when humans came across to North America from Asia and began to hunt mastodons. Well, almost the same. The short-grass prairie has changed. Sagebrush, a staple of old Western movies, is everywhere, the result of over-grazing by cattle and sheep as far back as the early 1900s. When the buffalo lived on the plains in the millions, the land was still dry and sparsely vegetated. But the short grass dominated. The land was always harsh and never drew agricultural settlements of Indians. It did support abundant wildlife, although the buffalo were not here in their endless herds when the first humans hunted here. One school of thought is that the buffalo and the Great Plains evolved as the first Americans burned the prairie to keep it open.

The Musselshell River marks your passage into Garfield County, and you begin to see exposed rocks, many around sixty-five million years old. You now occupy several slices of time. You are in the present, driving back to what feels like the early twentieth century, or the eighteenth or seventeenth. But all around you the torn earth reveals the deep past, open for investigation.

The rocks of what geologists call the Hell Creek Formation are what you see from the road. The formation was named in 1907 by Barnum Brown, a paleontologist from the American Museum of Natural History, based on rock layers near Hell Creek. It is a mixture of sandstone and siltstone that is exposed in Montana, Wyoming, and North and South Dakota. The rock beds that make up the formation vary in thickness, or depth, from 170 meters in Garfield County, where Barnum Brown first identified it, to 40 meters in McCone County, Montana. The formation preserves somewhere between 1.3 and 2.5 million years, depending on different interpretations.

These are not just any million or so years. These rock beds are made of sediment deposited at the end of the age of dinosaurs. The Hell Creek Formation is probably the best record anywhere on earth of terrestrial life at the end of the Cretaceous era (210 million to 65 million years ago), just before and right at the mass extinction that wiped out about 35 percent of all species, including the dinosaurs.

The end of the Cretaceous era is marked in much of Garfield County at the top of the Hell Creek Formation by a dark line in paler rock. The line is coal, deposited just after the mass extinction, and marks the beginning, in this location, of the Fort Union Formation. This, at least, is a rule of thumb. Elsewhere in the world chemical markers give a very specific and clear way to mark the end of the Cretaceous. In eastern Montana, however, these chemical markers are not always present, so the process of refining the date at which the Cretaceous ended and the mass extinction occurred continues.

Nonetheless, the dark line, called the Z-coal by some researchers, is a stark reminder of the vertical progress of deep time. The abstract numbers in the millions may be hard to comprehend, but the rock, in varying color, marking the agonizingly slow accumulation of silt from overflowing streams, sand from beaches, or rotting plants transformed to coal, is there to see and touch.

The formation is rich with evidence of ancient life. Here, in this rock, there are dinosaurs, like the fossils of
Tyrannosaurus
that Barnum Brown found in 1902, although he didn’t know they were
T. rex
. Actually,
T. rex
had not yet been named. There are huge bone beds of
Edmontosaurus,
a duck-billed dinosaur, found at the boundary of North and South Dakota, apparently all killed in a storm surge from the shallow inland sea that covered the center of the continent.

There are numerous other dinosaurs from the end of the Cretaceous,
Triceratops
and the boneheaded pachycephalosaurs . And then, there are none. Ever again, anywhere in the world. Deposition of sediment that turned to rock continued in this part of North America. And there are plenty of fossils in rock beds from later dates that document other passages in the history of life, like the rise of the mammals. There are bird fossils. But the nonavian dinosaurs are gone. Forever. Locked in deep time, while the planet piles up rock, erodes mountains, and moves continents.

The extraordinary fact about Garfield County is that it presents so clearly one particular chapter in the history of the planet. The sixty-five-million-year-old rocks of the Hell Creek Formation are near or right on the surface, ready for further excavation. This formation has yielded railroad cars full of fossils, including the
Tyrannosaurus
skeletons in the American Museum of Natural History and the Smithsonian Institution, and, of course, the fossil skeleton of
T. rex
that sets this story in motion, a find that we nicknamed B. rex,
B
for Bob Harmon, who discovered it.

Here in Garfield County is the section of the Hell Creek Formation that is best known and most researched. This is a part of Montana that has a bigger sky than the rest of it, if that’s possible. It has only a thin layer of cultural deposition by modern Americans, or indeed by any other human beings who have passed through in the past thirteen thousand years or so.

Garfield County covers more than three million acres, almost five thousand square miles. It is roughly the size of Connecticut with a population of about twelve hundred, although it would not be easy to find them all. At the population density of Garfield County, four square miles per person, the island of Manhattan would be home to five people.

Jordan, the only town in the county, population about 350 and dropping, is where you end up after the seventy-five-mile drive from Winnett. Jordan is known among fossil hunters and fishermen as the last stop before they continue on their quests, often by heading down the same dirt road toward Hell Creek State Park. The fishermen are after the walleye in Fort Peck Lake. The land surrounding the lake is part of the Hell Creek Formation and yields fossils of mammals, reptiles, shellfish, and plants as well as dinosaurs.

Visitors to Jordan tend to remember the Hell Creek Bar. It has ice cold beer, chicken in a basket, and a long wooden bar at which ranchers, fossil hunters, fishermen, and, on occasion, reporters mingle. Jordan gets more press than you might imagine for a town its size. Part of it is for the dinosaur fossils. It has been a town of note to geologists, paleontologists, and their audience since the days of Barnum Brown at least.

But it has some more recent claims to fame, not all savory.

In 1996 Jordan was the site of a small rebellion against the United States on the part of a group called the Freemen, a white supremacist militia that specialized in bank fraud. The group were followers of Christian Identity, a creed that holds that white people were descended from Adam and Eve and Jews and people of color from Satan and Eve. They did not recognize the United States, and set up their own banking system, which consisted largely of a computerized forging operation that brought in a total of nearly $2 million, according to the government.

The Freemen, led by LeRoy Schweitzer, conducted courses in forging financial documents, filed so-called “liens” against government officials, and wanted to return the government of the country to white males and fight the international banking conspiracy, led, of course, by Jews.

By the summer of 1996 they had alienated all their neighbors in Garfield County, near Jordan, where they had set up a compound at the 960-acre Clark ranch. The FBI arrived in Jordan after arresting several of the leaders who were not at the ranch. The siege of an extremist camp might have turned ugly, but the death of seventy people at Waco, Texas, three years earlier in a raid on the Branch Davidian complex there was still fresh enough that what followed was a long, nonviolent siege—eighty-one days.

The siege stayed in the news intermittently, although there was only one death. An FBI agent died in an automobile accident when he ran off one of the unpaved roads in the area. The siege ended without any dramatic confrontations. Eventually the Freemen all left the ranch and many were arrested. Some disrupted their trials by refusing to recognize the court’s authority. The Freemen faced a variety of charges, including bank fraud, mail fraud, and armed robbery. Eight of the men received twelve-to-eighteen-year sentences. Others received lesser sentences and LeRoy Schweitzer, the leader, was sentenced to twenty-two and a half years and is still in prison.

The Freemen standoff caused painful divides in families, between brothers and sisters, and parents and children. Many of the people who lived in and around Jordan thought of the Freemen as a cult. This was before Montana State set up a dig at Hell Creek, but our research staff was touched by the events, as were many people in Montana, who saw friends, neighbors, and relatives somehow drawn into the Freemen. Mary Schweitzer, who, as I mentioned in the introduction, led the research on the fossil bone tissue of B. rex, was connected by marriage to LeRoy Schweitzer, the leader of the group. He is the brother of her ex-husband.