The Bone Hunter: Paleontologist Michael Voorhies Uncovers Dinosaur Fossils
An article in the local daily about paleontologist Michael Voorhies got me excited about interviewing and profiling him, and after a simple inquiry I made arrangements for New Horizons editor Jeff Reinhardt and I to visit the scientist at his home dig — the very cool Ashfall Fossil Beds State Historical Park in Nebraska. It was a fun field trip and I thoroughly enjoyed capturing this engaging man’s magnificent obsession for bone hunting. This was another of those occasions when I never heard a peep from Voorhies after my article appeared in print. Perhaps now that it is getting a second life courtesy this online posting, I might hear something back from him.
©by Leo Adam Biga
Originally appeared in the New Horizons
There’s a perfect symmetry to bone hunter Michael Voorhies’ life.
The most significant fossil finds by this professional paleontologist have come in his native Nebraska. He found his first dinosaur bone as a child in northeast Nebraska. Soon after graduating from the University of Nebraska-Lincoln he discovered a prehistoric frieze of two dueling mammoths in the state’s far western Little Badlands. Within his first decade in the field he identified a volcanic ashfall fossil bed on an Antelope County farm near his childhood home that led to the establishment of Nebraska’s most unusual state park.
The ancient remains of Ashfall Fossil Beds State Historical Park are open to the public even as the area remains an active excavation site. This retired UNL curator of vertebrate paleontology now spends his summers there with his geologist wife Jane. They make their “bone camp” in a primitive cabin by a creek. She plays the harpsichord and cooks gourmet meals. They have a ball.
His parents still live in his hometown of Orchard, Neb. — a virtual stone’s throw away from Ashfall, where his life and career as a bone hunter have come full circle.
“I eventually ended up pretty much where I started,” he said.
Voorhies could be doing most anything in retirement. But he prefers scratching and digging around in the ground with his ever-present trowel, using a fine paint brush to clean the silty ash and sand away from whatever remnant he extracts. Holding a freshly unearthed object with relic-like care close to his thick-lensed glasses, he inspects it, hoping for a treasure rich in scientific discovery.
Whether sifting through dirt turns up a treasure or not, it still connects the seeker to a long lost age, even a bit of eternity. It also yields a measure of posterity.
“Every time you swipe through the dirt and you find a bone you know for sure you’re the first person in the history of the universe to see it, and that’s pretty good,” he said.
Bones represent pieces, no matter how small, of an epic tale.
“They all tell some kind of a story,” Voorhies said.
He derives the same joy of discovery from bone hunting today as he did as a boy along streams near Orchard, where his father was a dairyman and the paternal grandfather he idolized was a pharmacist. After one of these youthful tramps that his grandpa sometimes joined him on, Voorhies would empty his pockets of arrowheads, agates, bird shells and plants.
Once, at age 9, he came home with the remains of a tooth he suspected must be very old. He found it scouring the banks of Verdigre Creek. His favorite teacher at school, Mrs. Carlson, sent a letter along with the incisor to Lloyd Tanner, a paleontologist at Morrill Hall, the state natural history museum in Lincoln, asking if he could identify it for her eager student. In his reply Tanner confirmed the tooth belonged to a giant Ice Age camel that lived about two million years ago.
“That really made my day when I got a letter back saying this little hunk of stuff turned out to be something important,” Voorhies remembered.
Tanner sent the fossil back suggesting it’d make a fine specimen for the museum’s collection. Voorhies donated it and a part of him was forever hooked on the ancient wonders contained in the ground, although, he said, “it wasn’t until I got to college I realized you could be a professional paleontologist. This, to me, was some kind of hobby but here were folks making a living doing this.”
It turns out Nebraska’s fertile ground for fossils.
“Almost any of these little creeks in this area carry a load of gravel that has scattered pieces of petrified bones, wood and teeth and so forth,” he said. “If you have any outdoor experience in this part of the state you’re going to find fossils.”
The Nebraska Panhandle is especially abundant in fossils.
He credits both Mrs. Carlson, whom he recalls as “a superb science teacher,” and Tanner for inclining him towards the work he does now.
“I was not a junior scientist. My interest was mostly being outside. If I hadn’t had the teacher I had growing up in Orchard, if she hadn’t nurtured that interest in natural history I had, I think there’s a good chance I could have ended up pushing pills some place and been perfectly happy at that. She encouraged curiosity and creativity in kids. And I’m forever grateful to Lloyd Tanner for taking the time to answer a little kid’s question.”
When a child visiting Ashfall asks him a question, even one he’s often heard before, he responds knowing his answer can impact an impressionable young mind.
In that way his life has of coming full circle, Voorhies ended up working for the very man, Tanner, who certified his first dinosaur find.
Many more significant finds followed. Voorhies was a fresh UNL grad the summer of 1962, working in a field party at the Trailside Museum at Fort Robinson State Park, when two workmen laying electrical lines on the Tom Moody ranch near Crawford, Neb. came in with a large fossil they’d uncovered. They’d placed their find in the only available container — a feedsack — and presented it to Voorhies.
The fossil’s size readily identified it as belonging to a mammoth, the largest dinosaur to roam prehistoric Nebraska. Voorhies and the team went to the site where the hind leg bone laid undisturbed for thousands of years and they spent much time excavating before confirming a once-in-a-lifetime find.
“We had no idea what we were getting into until we dug back into the bank. We dug forward to where we hoped the skull would be and, Wow!, there it was — the back of the skull. I remember there was a moment at which we were disappointed because we found the tip of a tusk and it was going the wrong way. ‘Oh, damn, the tusk has broken off and gone back the wrong way..’ But within a few more days it was apparent there was a second elephant — and that tusk tip was actually from” the second until-then-obscured mammoth.
“So it gradually dawned on us this was a very unusual fossil.”
It took six weeks of digging before the intact skeletons of two fully grown adult male Columbian mammoths frozen in a death embrace emerged; their intertwined bodies evidence of a fight that ended when their tusks became interlocked and the beasts fell, unable to dislodge their ivory appendages or lift their 10-ton bodies.
He said tests run on the tusks indicate the elephants engaged each other “in a testosterone rage. That’s when they’re the most dangerous. Basically, two 10-ton trucks meeting head on.” It was, he said, “the old story” — a fight over sex. What caused these two battling elephants to be fatally entangled, he said, was the fact each had one long sharp tusk and one stump, allowing the spear-like thrusters to get caught up — one’s tusk lodged in the eye socket of the other elephant.
It remains the single most impressive fossil find Voorhies has ever seen.
“This is the only case we know of in the world where you find these elephants locked in combat,” he said.
The mammoths were dressed in a plaster jacket and removed from the ground without breaking a single bone. The fossils were then brought to Morrill Hall, where they remained until a couple years ago, when funds were finally secured for Voorhies and a crew to prepare the mammoths for display at Trailside.
In hindsight he would have left sediment on the bones for the added information it provided. But being green and afire with the heat of discovery, he “was after the trinket — the bones,” he said, not the sediment. He knows better now.
Nine years after the mammoths discovery Mike and Jane were on one of their cherished hikes near Orchard when he spotted something that changed his life.
A baby rhino skull exposed by erosion proved to be the marker for an ancient fossil bed. What used to be an active water hole for dinosaurs became a dead zone when volcanic ash descended there, killing off the natural habitat and the many animals that utilized it. The find led to Ashfall State Park outside Royal, Neb.
Several features distinguish this spot, he said, none more than its rhino, three-toed horse and other skeletons preserved in perfect three-dimensional condition within the very earth that became their burial ground. The sculptural bones jut out of the gray ash like headstones in a dinosaur graveyard. It’s a striking, eerie, solemn, magisterial sight. The tableaux-like remains are protected from the elements in a rough-hewn mausoleum called the Rhino Barn.
“Probably the most unique thing about Ashfall is that we’ve left the fossil bed in the ground so people can get close to it,” he said. “This is the only place in the world that has skeletons of large animals in the round. Their rib cages are still bulging up just like a live animal and that’s really what makes this place unique.”
Ashfall’s distinctive enough that the PBS series Nova featured it.
“What Ashfall has contributed is much more specific knowledge about one particular place and the details of the anatomy of these prehistoric animals. Most fossils are very incomplete. We knew for instance we had rhinos (in ancient Nebraska) but we didn’t really realize this particular species had very short legs. It was built like a hippopotamus. You have to have whole skeletons to figure things like that out. One of the nice things about Ashfall is that it took the guess work out of it for many of these species.”
Voorhies is a storyteller at heart and he likes nothing more than adding to the evolving narrative of prehistoric times.
“One of the pleasures of paleontology is being able to sort of time travel in your imagination and try to imagine what things looked like when they were alive,” he said. “And if you have really good evidence like we do at Ashfall you don’t have to speculate so much The natural body line has been fleshed out. You can see the sag of the belly…”
The more scientists have to work with the more they discern. “We have such excellent materials in the horses and the rhinos we can tell the sexes easily because the males have big tusks and the females have small tusks,” he said. “Many of the females have babies right next to them, some in nursing positions.”
Many of the skeletal remains include stomach contents, complete with undigested seeds and stems of prairie grasses. “Their last meal,” Voorhies said. Thus, scientists theorize most every critter in the ash bed was a grass-eating animal.
“One of the fascinating things to me is how rich the wildlife was here 12 million years ago,” he said. “I think we’re up to something like 70 different species of wild animals that we have evidence were using this water hole. The biggest ones were the elephants and then you work down to rhinos, three-toed horses, various kinds of meat-eating animals — bear dogs, bone crushing dogs and saber-toothed cats — right down to mice, squirrels, shrews, frogs, toads, salamanders, bats and birds. Just all kinds of things.
“Also, we have several new species of animals found here that have never been found anywhere else on Earth, including a type of bird very closely related to the Crowned Cranes of Africa.”
Ashfall might have been lost to the ages if not for what Voorhies calls “a stroke of blind luck.” At the time he discovered the site in 1971 he and Jane were professors at the University of Georgia, where they met. That summer, as was their habit, the couple came to Nebraska to do some bone hunting. They lived like gypsies.
“Every summer we came out here and continued to explore the fossil beds in this area. We visited, oh, probably 60 or 80 farms during the summers of ‘69-’70-’71. We didn’t have a child then so we lived out of the back of our station wagon and sort of went from camp ground to camp ground. I spent my days very pleasantly hiking around country like this,” he said, gesturing to the park’s rolling hills and valleys.
“To me, one of the great joys of paleontology is being out in the environment…”
In later years the couple’s daughter, Harmony, joined them on their treks, developing “a love of the outdoors” in the process, according to her father.
In the early ‘70s, unencumbered by grants or institutions directing his work, he said, “I was pretty much my own boss and so I did basically what I wanted to do — explore the geology and paleontology in northeast Nebraska, which is my home. We found probably a hundred fossil sites in this part of the state and made friends with a lot of land owners up here who encouraged our work.”
Bone hunters, like game hunters, enlist the cooperation of farmers and ranchers to pursue their passion.
“The fella that owned the farm here, Melvin Colson, gave permission to search the grounds. I spent two or three days looking around this 360-acre farm, starting in the obvious places. There’s a high cliff on the other side of the valley which has a nice sandstone bed and there are petrified bones in it,” he said. “So I was perfectly happy. Some of them were worth collecting and some of them were not.
“I made my little map. There was a volcanic ash bed right where there should be at the bottom of this sandstone cliff. I made my notes. Then I wandered over on the other side of the valley. It looked like there was a gully cutting back into Mr. Colson’s corn field. It looked mostly like black dirt, not very old, but once I got in the gully it turned out it was a very nice slice through the bed rock and lo and behold here was the volcanic ash just in the right spot. It was 10 feet thick.”
Immediately he speculated the ash had drifted into what was once a water hole.
“Then there was this little skull that took my eye. Wow! In my business we mostly find broken specimens. Teeth, leg bones, basically the dog’s dinner. A lot of bones have been extensively chewed on by scavengers or trampled on by larger animals. It’s very rare to see the skull with everything perfect. But there it was — a little baby rhino just basically grinning out of the wall.”
Fate led Voorhies to it.
“If I had happened to not walk up the little ravine I happened to walk up that day I’m sure I never would have seen the fossil, so little of the bone was exposed,” he said. “It just happened that erosion had clipped the edge of this very large bed. Most fossil beds, by the time you find them, have mostly or partly been washed away. But Ashfall was exceptional in that the whole time capsule was right there. Nothing has been destroyed by the weather. We were extremely lucky.
“If I had visited that same spot a few years later these fragile fossils would have been destroyed by the weather. So it’s one of those cases of being there in the right place at the exact right time.”
None of that was apparent then. Even after examination all Voorhies saw exposed was that lone skull. Nothing else suggested the treasure trove buried beneath his feet. It took excavations over decades, some funded by the National Geographic Society, before the full extent of Ashfall was revealed.
“There was no sort of eureka moment for me,” Voorhies said. “It wasn’t actually until years later it became evident this was a very large bone bed.”
Mining Ashfall for fossils continues. “We have a lot more to find out here,” said Voorhies, who added the site will remain active as long as the park remains self-supporting through the admission fees and gift shop revenues it collects.
The fact he made the discovery is ironic as his eyesight’s impaired.
“I’m not an exceptionally good fossil hunter,” he said, “but I’m persistent. And like my grandfather used to say, ‘Even a blind nag gets an acorn now and then.’”
A single fossil that leads to a bone bed that draws sightseers from all over the U.S. and the globe is not an every day occurrence. An article Voorhies wrote for National Geographic Magazine brought much attention to the site. Benefactors provided funding to develop Ashfall State Park.
This tourist stop that attracts 25,000 visitors a year owes its very existence to chance. Voorhies said even if a fossil ends up exposed by natural erosion or human construction, the two agencies that bring fossils to the surface, “you sort of have to have a trained eye to appreciate what you’re looking at.” His expert eye just happened to notice the rhino skull.
Still, he said, “I don’t think anyone would have walked away from this baby rhino — it looked too much like a head. But many fossils really don’t look like anything at all. Most dinosaur bones, for instance, look basically like pieces of junk until they’re very carefully cleaned off and glued back together.”
The site’s fossils are so well preserved thanks to the blanket of ash entombing them. Its low acid, alkaline levels did not chemically damage the bones.
“A neighboring farm lady used the ash to press wildflowers,” Voorhies said. “Normally wildflowers lose their color in a few weeks but she was able to keep them fresh looking for years.”
The white volcanic ash, Voorhies said, “is extremely fine grain. It feels like talcum powder.” A natural abrasive composed of many tiny glass particles, the ash was long commercially mined from a central Nebraska site by the Cudahy packing company in Omaha, said Voorhies, where it was shipped by the railroad car full, combined with soap, and sold as Old Dutch Cleanser.
When the ash fell millions of years ago the animals that inhaled it could not expel the abrasive substance from their lungs and they died a slow, agonizing death. The smallest animals perished first. The last to die were the rhinos. The same ash that killed the animals served as a preservative that allowed modern man to discover the remains and extrapolate what transpired.
Where did the ash originate from?
“We’ve never had a volcano in Nebraska,” Voorhies said, “but the eruptions in the Rocky Mountains and farther west” send ash clouds into the jet stream and the prevailing winds carry the fallout over thousands of square miles. Nebraska included. “Even Mount St. Helen’s in 1980 deposited a little bit of ash here. Not enough to make a layer. The fossil record in Nebraska is studded with layers of fallout, which are exceptionally interesting to geologists and paleontologists because they can be dated very precisely with the radioactivity clocks. So that’s why the ashfall here we know is 11.83 million years old,” he said. “Pretty much the whole record of evolution here in the Great Plains is calibrated by its ash beds.”
The ash bed that includes Ashfall can be traced throughout northern Nebraska, across Wyoming, to a large crater in southwestern Idaho. “So the known extent of this ash bed is a thousand miles,” he added. “Obviously, it’s been eroded away in some places but throughout the Niobrara River Valley wherever the streams cut down to the right level you always find the ash bed.”
Ashfall accumulated so much fallout due to it having been flatlands — part of an African-like savanna. The fallout’s thickest in the water hole depression, where the powdery ash drifted, like snow,. It’s here the most skeletons are found.
“Before this depression with the water hole in it filled to the brim with ash thousands of animals died by breathing in the dust,” he said. “So the critters are actually found at the bottom of the ash bed. The whole thing probably took several months from the time the ash first fell until the animals were dead and the carcass bed was covered with volcanic dust.”
The enclosed Rhino Barn with the intact skeletons is the star attraction at Ashfall, but many other fossil beds exist there.
“There’s a layer of sandstone under the volcanic ash which actually in many ways is more rich in fossils than the ash bed itself,” Voorhies said. “It would be the accumulated bones, teeth, jaws, skeletons of animals that had used the water hole probably for many centuries before the ash came.”
The tan or yellow sandstone layer provides a sharp contrast to the grayish-white ash, alternating stripes that mark the millenia and encase the past.
Visit Ashfall this summer and you’ll likely see Voorhies examining fossil finds in a trench being dug by strong bodies wielding shovels along one side of the Barn; the open ground’s striated layers of ash and sandstone clearly visible. The trench, whose manual labor is provided by college students working internships on-site, is part of a planned expansion. When completed by Memorial Day 2009 the fossil excavation/exhibition area will be eight times larger than today.
Fossils are harvested all the time from the trench. Some qualify as what Voorhies calls “significant finds,” albeit small in size. “There’s something new every day.”
Students pitch in more than strong backs — they train sharp eyes on digs.
“Some of the really critical discoveries at Ashfall are made by students,” Voorhies said. “They have good observational skills. They see things through fresh eyes. Some develop a knack for it — like they’re almost born with it.”
Voorhies speaks with admiration about the bone hunters — past and present — whose “natural eye” have led to discovery after discovery.
“Some of my colleagues down at the museum are almost phenomenal as to what they can find,” he said. “I would walk over something and then my buddy would reach over in my footpath and say, ‘You missed this.’ It’s always kind of a joke.”
No joke are the “legendary folks” who preceded him in the field. State museum founder E. H. Barbour was a bone hunter in pre-mechanized times when hauling a heavy elephant fossil out of Devil’s Gulch in western Nebraska required a team of horses.
“Yeah, there was sort of a heroic breed of really pioneer paleontologists that worked in the fossil beds in the old days. Now it’s basically just a couple of clowns in a pickup truck,” Voorhies said, smiling.
He said “a guy who truly did have a sixth sense for fossils” was Morris Skinner, a Museum of Natural History (New York) paleontologist for half-a-century. “As a high school student he found a fossil rhino bone bed on a ranch near his hometown of Ainsworth.”
“He collected just magnificent fossils. Even in his later days he still had an amazing eye for fossils,” he said. “He was a mentor to a whole generation of Nebraska paleontologists like me. He took us out and showed us. He was an expert at reading the rocks, at reading geology. He taught me how to take the anatomy of a hillside by using a simple instrument — a hand level.
“Levels are what we use when we’re out prospecting. It’s very important in paleontology to know exactly the level where a fossil comes from. If you’ve not recorded exactly the level of each fossil you bring in then they’re totally useless. Making maps is really a basic part of our job.”
Besides the dramatic image they make, an advantage to leaving the bones in the ground at Ashfall, he said, is that “in 30 years somebody a lot smarter than me is going to be able to get much more information on those skeletons with new technologies. If we simply took all those bones out of the ground and brought them back to the museum that contextual information would all be lost.” As accurately as he assembled the mammoths at Trailside to replicate what they looked like in the ground, he said, “it’s not like seeing the real thing — the way Mother Nature left it. It’s really not pristine.”
Nebraska remains prime ground for fossils, which people often bring Voorhies for study. Inside the Ashfall visitors center is a lab where the public’s finds are examined alongside those of the paleontologists’. A case out front contains donated fossils. A couple from Basset recently brought in parts of a rare leaf-eating animal’s skeleton. Students will reconstruct the skeleton this summer.
He said the public in Nebraska “has been just outstanding” in supporting paleontologists’ work in the state. “I’m very proud of our state’s tradition of being at the cutting edge in this science.” He suspects the fact that fossils “are so common here” accounts for Nebraskans’ generosity.
Just as not all fossils hold the same interest for him, not all fossil beds spark the same excitement.
“I suppose I have a weakness for mass death. I like bone beds where you have lots and lots of animals, lots of death and destruction, and trying to figure out what happened. To me, it’s the intellectual challenge of trying to reconstruct the past.
The biggest one I ever worked on myself is either the Lisco Camel Quarries or the Broadwater Horse Quarries, both of which cover several square miles.”
By comparison, the Ashfall bone bed covers a couple acres.
“One of my favorite fossil beds we call the mouse mine. It’s hundreds of thousands of petrified bones, mostly small animals. Mice, frogs, weasels, otters, beavers. This is an Ice Age pond deposit just crammed with bones.”
The more diverse a fossil bed the better.
“I do like variety. I guess I would get pretty bored if I were working a site that only had one species.”
He calls what he does “a safari with a shovel” and he’s only too glad his prey lay dormant in the ground for him to hunt down. “It’s a good thing I don’t have to go after them with a gun,” he said, “because I couldn’t hit anything.” He hopes to turn out a book on Ashfall in the next couple years.
How apt that this bone hunter’s fossil odyssey, which began with a letter, then peaked with an article, may now culminate in a book.
- Tiny Fossil May Be New World’s Smallest Dinosaur (inquisitr.com)
- Some dinosaurs may soon go extinct from record books (news.bioscholar.com)
- Paleontologists Define Fossil Records as all the Fossils Found on Our Planet (brighthub.com)
- X-rays Reveal Colors of First Birds (wired.com)