NEWCASTLE, Wyo. (AP) - For years this land sat unexplored, eroding at the change of seasons, in the Wyoming wind, under the hooves of cattle.

When rancher Mike Harris moved here in 2004, he found bits of the past lying on the surface: bone shards, fragments, pieces that together formed a Triceratops horn.

He once let an amateur digger search for bones. The guy wasn't there long, didn't find anything. Harris didn't think much of it.

The earth below his 14,000 acres remained dormant.

Until now.

Through a neighbor, Harris met Tom Lindgren, a commercial paleontologist based in Tucson, Ariz. Lindgren began excavation on the Harris ranch last month.

In a way, they need each other, rancher and digger.

For Harris, it was the opportunity to uncover what really lies beneath those shards on the surface and possibly save his land.

For Lindgren, it was the chance to get out of the office and back in the dirt, living that lifelong dream most people let slip away.

Shovels, knives and brushes are the tools of Lindgren's trade.

Dig into this soil, and you move back through 65 million years of history. It was low altitude and swamp-like then, a flooding environment ideal for preserving the dead. Fossils would have remained hidden in layers of sediment, but the rise of the Rocky Mountains brought the past to the surface.

Recent weathering exposed even more on this land.

The first full day on site, Lindgren and a crew of two slowly peeled away layers of dirt around Triceratops vertebrae and parts of a skull. They used cyanoacrylate glue to keep fragile parts from breaking to pieces. With stakes and yellow cord, they set a 12- by 20-foot grid and mapped their site on graph paper.

It's how Lindgren has worked his entire career.

He learned from some of the greats, including Lance Grande, one of the world's leading experts on the paleontology of the Green River Formation. Beginning in the 1980s, Lindgren ran his own commercial fossil fish business, sometimes working 16-hour days to excavate some 500 fish. He's been working with Wyoming fossils for more than 30 years.

"I realized you could make a reasonable living doing what you love," he said.

Some of Lindgren's specimens have been sold to institutions across the world, including the American Museum of Natural History in New York, Museums of Scotland, the Field Museum of Chicago, the Denver Museum and the Smithsonian.

In 2001 he opened his company, GeoDecor, which sells fossils and mineral specimens to researchers, collectors and interior designers. He also serves as co-director of natural history auctions for international auctioneer Bonhams and Butterfields.

Critics of commercial paleontology argue that fossils should be reserved strictly for educational and scientific studies because they are irreplaceable.

In defense of the commercial side, Marion Zenker of the Black Hills Institute of Geological Research argues that vertebrate fossils are everywhere.

"When they say vertebrate fossils are rare, if you know, you can't help but laugh, Zenker said.

Federal and state laws heavily regulate paleontological work on public lands. Those in search of fossils need private land to truly break through all those layers of sediment.

It's why finding a landowner to work with is essential to Lindgren's work.

Where research institutions and museums lack funding to support frequent digs, commercial paleontologists and even amateurs can pay their own way. It is they who often bring new discoveries to light, Lindgren said.

And unless someone removes the fossils, as Lindgren explains, they will only continue to erode with time.

At the first dig site on the Harris ranch, bones that once looked promising appeared less than ideal by the end of the first day. Lindgren was frustrated. He wanted to find well-preserved bone, a skeleton, clues as to where to move next.

The fossils sat too close to the surface for too many years, constant freezing and thawing eating them away, Lindgren said. Pieces crumbled and felt spongy, like moist cake.

These days, rancher Mike Harris has been letting his horse move the cattle. He keeps his eyes on the ground, scouting for fossils and marking new locations with GPS.

"It just blows you away," he said. "Now I'm looking everywhere. It's kind of like playing poker - it can get in your blood pretty fast."

Harris found his biggest discovery a few years ago. First, he saw a lump of bone the size of a softball, just sitting on a dry patch of ground unobstructed by sagebrush. Six feet away, he spotted a second piece. Fifteen more feet, a third.

The lumps fit together like a puzzle. It was a Triceratops horn.

Nothing compares to finding that fossil. It connects him to his land.

Harris' decision to allow excavation comes in part from his efforts to challenge a proposed $6 billion expansion of the Dakota, Minnesota and Eastern Railroad that would cut through his ranch. The expansion would create 262 miles of rail from western South Dakota to the Powder River Basin coalfields.

Harris hopes a discovery could illustrate the value of his land. Should construction begin, Harris wants to be compensated for his bone beds, he said.

"If you have something out there of value," Harris said, "why let it go to waste?"

Expenses on the ranch have risen 70 percent in the last five years, and the cost of cattle has dropped, he said. There's no doubt a major discovery, or monetary compensation, could help.

But by now, after spending time with Lindgren, Harris' search for dinosaurs has become about something more than money.

"There isn't enough money in the world to buy this horn from me," he said, referring to his first Triceratops discovery. " ... This makes you realize that you're just a speck in all of time."

The picture of what used to be here emerges slowly.

Diggers go in blind, relying on their ears to tell them when they've found something. They remove layers of soil less than a half inch at a time. They wait for a grainy, raspy sound.

On the second day of digging, Lindgren explored a second site, hoping it would be better than the crumbling bones at the first.

His team already had identified an intact Triceratops horn there. Lindgren would find something else.

At first it was all questions. He knelt in the dirt with a small knife and brush.

"What is that? There's bone on either side ... ,'' he trailed off, pointing to the small hole in the ground. He brushed away more dust. Twenty minutes passed.

"Why is that there?" He pulled back sagebrush roots that clung to bone. "Look at this, it's strange."

He shaved off more soil.

"More bone? Is that possible already?"

It was a jawbone, solid and in good shape. Perhaps two jaw bones, collapsed onto one another.

A few inches away, bone fragments.

It was possible, he said, that this dinosaur was eaten.

"This could be part of a bone, or it could be a big find - you just don't know."

In the past, Lindgren has spent hours digging only to uncover a small leg bone with nothing else around it. But he knows to be patient.

Where there are fragments, there could be bones. Where there are bones, maybe fully articulated skeletons.

Throughout the day, Mike Harris rides over on his ATV. He checks in on the progress, inquires about new discoveries and asks Lindgren to ride with him to new potential dig sites.

Throughout the summer and into the fall, Lindgren will continue digging here. And Harris will continue scouting.

Perhaps together they might make that big find. Lindgren knows it's out there, somewhere, hidden under the surface.
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Information from: Casper Star-Tribune - Casper, http://www.trib.com.

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