Bones of Contention : It has all the ingredients of a Western: a rancher, a big-city interloper and a range war. But this skirmish over evolution doesn’t star cattle. It’s over dinosaurs.

Here’s an idea for a dinosaur movie:

A big-city paleontologist discovers dinosaur bones on a Wyoming ranch. Maybe millions of bones, adding up to a herd of perhaps 8,000 giant duckbill dinosaurs.

Naturally, there’s a catch. The duckbill graveyard is on land owned by a Christian cowboy so opposed to evolution he won’t even let anyone lecture about it on his ranch. Despite their differences, the scientist and the rancher become friends. Both are fascinated by the fossils and both want to build an educational field station. But neither will budge on how life began.

The scientist won’t be a party to teaching creationism; the rancher threatens to turn the whole dig over to a “creation paleontologist.”

Imagine a high-plains version of “Inherit the Wind.” In the Wyoming version, no one is threatened with jail over evolution, but the future of a major scientific discovery is at stake.

Meet paleontologist Kraig Derstler and rancher Glenn Hanson, the ontological odd couple who are living the movie in real life.

Derstler discovered the Dragon’s Grave bone bed on Hanson’s ranch last summer. But if the two men can’t agree on a lease for the site by Aug. 12, Derstler might lose the right to dig the bones.

Derstler, 40, is a professor of paleontology at the University of New Orleans. His prematurely gray hair gives him the distinguished, academic look you’d want for the movie. On a dig he favors blue jeans, running shoes, T-shirts and a blue bandanna.

Hanson, 77, has lived all his life on the ranch his father homesteaded in 1908. His jeans aren’t as faded as Derstler’s, but his belt buckle is much bigger. At 6 feet, 2 inches tall and 180 pounds, wearing a beat-up cowboy hat and battered cowboy boots, Hanson is right out of Central Casting too.

The cowboy and the scientist met in 1990, when Derstler began exploring the Lance Formation in eastern Wyoming. The Lance is a crescent-shaped sandstone outcropping, one of the most fertile dinosaur fields on Earth. It runs 100 miles from Lance Creek in the south to the Montana border in the north and is 20 miles across at its widest point.

Paleontologists first found bones here in 1888 (the Triceratops horridus is the most common Lance specimen), but in 1900, just two miles southeast of the Hanson ranch, Barnum Brown discovered the first complete Tyrannosaurus rex skeleton. It is still on display in the British Museum.

The Hanson ranch is smack-dab in the middle of the Lance.

“My sister and I used to gallop around these hills and see these bones everywhere,” Hanson says, although he admits he was more interested in the buffalo skulls.

Last summer, Hanson led Derstler to a rugged system of gullies that Derstler would later name Dragon’s Grave.

“There were just tons of bones on the surface,” Derstler says. “That means there’s hundreds of thousands beneath the surface, and more likely millions.” Most of the bones belong to one species, the three-ton, plant-eating Edmontosaurus annectens , commonly known as the duckbill dinosaur. By Derstler’s conservative estimate, the remains of 300 duckbills lie buried here. His reasonable estimate is 3,000. His liberal estimate is 8,000.

Derstler says it will take a decade to excavate this site. He wants to set up a field station to support a long-term dig and to teach paleontology. Some bones would be displayed at the site. Others would go to a Wyoming museum.

But first he needs a lease from Hanson. That’s a problem.

*

Glenn Hanson flat does not believe in evolution.

“I think God created everything,” he says. “You look at the flowers, the grass, the sun coming up every day. I just do not believe all that happens by accident.”

A lot of “all that” happens here. The 8,000-acre Hanson place is in big country, right out of a John Ford Western.

The Black Hills of South Dakota loom on the eastern horizon, 35 miles away. On a clear day, you can see the Laramie Mountains 50 miles south. Prairie dogs, horned toads, rattlesnakes, deer, antelope, coyotes, foxes and golden eagles live here. Hanson’s father cleared out the last den of gray wolves in 1913, but mountain lions are making a comeback.

A newcomer might call the ranch desolate, with its sagebrush, prickly pear cactus and barren gullies. Hanson would disagree. He says the native grasses are rich in protein: “It’s almost like feed grain.” And the Cheyenne River, which runs through the ranch, provides bottomland for hay.

The ranch offers history lessons too. There are remains of tepee rings and a homesteader’s dugout. Hanson collects Native American artifacts, and an archeologist told him one of his lance points was 8,000 years old. Hanson believes it, although some creationists put the age of Earth at 6,000 years. “This Bible’s been translated from several languages, so there’s room for error,” he says.

But not much error. Hanson refuses to believe dinosaurs are millions of years old. He thinks man and duckbill coexisted only thousands of years ago. “I absolutely do,” he says. “They all went together.”

Hanson is an odd sort of creationist. For example, he has never been a regular church-goer. The nearest town, Newcastle, Wyo., is 40 miles north. When he was a boy, that meant a six-hour ride on horseback. “Five, if you didn’t think too much of your horse.”

He says he never worried much about creation or evolution. He was too busy breaking horses for $5 a head. “When I started getting $10 a head, boy, I was in the money.” He married his wife, Phyllis, in 1939, and they raised five kids. Today, a daughter runs the ranch, but Hanson helps.

He also reads the Bible and creationist literature, which claims, among other things, that human footprints have been found next to those of dinosaurs and that Charles Darwin recanted evolution on his deathbed.

“I didn’t start out to be a creationist, but I’m getting to be one more and more,” Hanson says.

Paleontologists who visited his ranch in the late 1940s told him the dinosaurs were 250 million years old. “Now they are saying 65 million years. They got quite a bit younger in the last 45 years.”

Hanson thinks the dinosaurs will continue to get younger. “Ever since Darwin, they’ve been trying to dig up evidence that one kind of animal has changed into another kind, and they haven’t done it yet. I think Kraig will admit that.”

*

Derstler will not admit that. He says there is plenty of evidence for evolution, ranging from relationships in the fossil records to observations of live animals.

He also points out that ages of dinosaurs have been established by radiometric dating, fission-track dating and thermoluminescence, all of which produce a similar conclusion: The dinosaurs disappeared about 65 million years ago.

Like Hanson, Derstler is fascinated by the natural world. His home in New Orleans is a menagerie. Derstler’s wife, Debbie Pearson, is the education director of the Audubon Zoo in New Orleans, and she has permits to keep wild animals, including a coyote, a Harris hawk and “tons of snakes, frogs and turtles.”

Derstler also shares Hanson’s interest in buffalo. He wants to reconstruct duckbill dinosaur skeletons near a live buffalo herd to show similarities in bone structure.

Derstler grew up on the edge of Pennsylvania’s Amish country, but he doesn’t belong to an organized religion. He is more likely to read the Tao Te Ching than the Bible.

“I find in both of them great beauty and wisdom, but I don’t find the truth in either one,” he says. He regards their stories as “illuminating myths,” not factual accounts. Derstler’s worldview: “It’s a big, beautiful, glorious world that happened by chance.” But that’s his opinion. For facts, he turns to Dragon’s Grave, the ideal dinosaur-dig movie set.

*

Dragon’s Grave is dominated by five major ridges separated by deep gulches. Derstler’s crew is digging on Ridge 2-C, which offers a view of the Hanson house two miles to the south, the Cheyenne River beyond that and a ridge 15 miles distant.

“Ranchers around here call this ‘rough country,’ ” Derstler says. In fact, the bone crew had to camp half a mile away. They haul most of their equipment in on foot.

The Lance Formation sandstone is so soft you can carve your initials in it with a dull knife, which makes it perfect for digging fossils. The crew had found more than 200 bones by mid-July, including a large duckbill jawbone. But Derstler says the eggshell fragments they found and the tiny jawbone from a baby duckbill are even more exciting. Some experts think that duckbills hatched their young on higher ground, near Canada, then moved into the swampy coastline that later became the Hanson place. The egg and the baby’s jaw could change that theory.

*

Hanson would throw out the entire theory. He insists creationism is science and evolution is wrong. A field station on his ranch would have to represent that view, which Derstler cannot abide.

After an evening discussion recently, both men were pessimistic about the future of Dragon’s Grave.

“If we can’t come to a better understanding, I don’t think it’s going to go,” Hanson says. “He just said, ‘Science isn’t based on truths, it’s based on theories.’ ” To Hanson, that is paramount to saying evolution is hogwash.

Derstler says Hanson misunderstood him. “Truth is something that requires a God’s-eye view of the world, and scientists don’t have access to that at all.” Instead, scientists start with facts and work toward theories. If new facts don’t match the old theory, they get a new theory. Derstler says creationists depart from science because they start with a theory and look for facts to fit it.

Hanson won’t debate the fine points of creationism. “I’m just a plain old cowpoke. That’s all there is to it.”

But he was disturbed when a group of children visited the site last year. “When I saw all those little kids up there, so interested, I just didn’t think we should teach them wrong.” What would be right? “There are creation paleontologists who are willing to come in here.”

Derstler says if Hanson brings in “creation paleontologists,” real science will suffer. Derstler says his own research will be set back three or four years.

This summer’s dig ends Aug. 12. The two men agreed on that as a deadline to settle the future of Dragon’s Grave.

Both insist that they will remain friends, no matter what happens. They have come to respect each other.

Hanson was grateful when the bone crew dropped everything to help put out a prairie fire. For his part, Hanson has been a gracious, generous host. His home is a message center for the bone crew. And Phyllis Hanson frequently sends goodies--biscuits and home-canned peaches--to the paleontologists’ isolated camp.

“The Hansons are wonderful people,” Derstler says.

“We do get along most of the day,” Hanson says. “But watch out in the evenings. We’re dangerous.”

Maybe. But neither man is likely to violate the admonition from Proverbs:

“He that troubleth his own house shall inherit the wind,” which is where the movie might have problems.

Spencer Tracy and Fredric March dueled in a hot Tennessee courtroom over the evolution of species. Wyoming is plenty hot in summer, but Hanson owns the land and the fossils free and clear. There will be no dramatic courtroom finish here--only silence should the digging stop at Dragon’s Grave, where seldom is heard an evolutionary word.

Edmontosaurus annectens

* Alias: Duckbill dinosaur.

* Weight: Three tons or more.

* Length: Thirty to 40 feet, head to tail.

* Height: Ten feet or more at the shoulder.

* Dining Habits: Plants (remains of conifers have been found in a stomach).

* Where They Roamed: Lowland woods, bogs and marshes of the Western United States.