A Grassy Heritage

“So much ash had fallen that it buried the watering hole and all food, so when the animals tried to eat

all they got was a big mouthful of ash. Also, the ash was so fine and powdery that every step an animal

took stirred up ash causing it to make its way into the animals' lungs. Eventually they all suffocated.”

-          Andria “Leigh” Skaff , former excavator/interpreter

            Just north of Highway 20, seven miles north of Royal, one of northeastern Nebraska’s unique attractions, the Ashfall Fossil Bed State Historical Park, lies in the predominantly Czech-settled Verdigre Creek valley.  Established in 1986, the park contains a plethora of Great Plains natural history, both living and dead.  Several feet below the vibrant green and golden grasses that rustle in the southwest prairie wind lies one of the most interesting fossil finds of the 20th century.  For miles around the attraction, rolling hills and valleys are ablaze with the bold colors of a summer prairie.  Yet the tall and short, savannah-like grasses were not always a staple of the landscape as they are in recent history. 

In fact, prairie grasses did not evolve until late, geologically speaking, in the Miocene Epoch, beginning about twenty-three million years ago, a period significantly warmer than the epochs both before and after.  Global climate changed during this time as Antarctica migrated to the South Pole and circumpolar arctic water patterns north of the largest continents reduced the mixing of warm and cold waters.  These changes, combined with the rise of the Rocky Mountains, led to significant drying of the North American continent’s interior and, thus, the evolution of grasses.  This is where the story of the Ashfall Fossil Bed really begins, twelve million years ago.

Now, adult admission to the park is $5.00, but as I already have a 2007 Nebraska State Park Permit on my vehicle, I needn’t worry about the extra $4.00 daily visitation fee.  I chat a few moments with a volunteer University of Georgia graduate student at the park entrance, before pulling into the parking lot across from the Visitor Orientation Center.  As I get out of my car, I hear the distant cry of a bird of prey, and looking up at the sky, I see a tiny speck flying overhead.  Rolling hills of prairie radiate for miles around, and a strong gust of wind blows particles of dust all around me.   It’s sunny and hot outside, and everywhere, the dry, crisp smell of the Nebraska prairie fills the air. 

Returning my gaze to the park, I am drawn toward a smaller, outdoor attraction just down and across the road from the Center.  Walking the short distance there, I see boxes full of various excavated material and minerals as well as placards highlighting some of the events of the Miocene Epoch.  Details of the flora, fauna, cultural, and natural history of the place occupy me for some time, before I decide to move on to the Center. 

Inside, I’m amazed by the quality and quantity of fossils, photos, drawings, and displays on view.  It’s like a miniature tour of the last twelve million years of regional history as the eyes of stuffed, predatory birds and other animals stare down upon me, crying, challenging, Who are you?  What gives you the right to intrude upon the land of our forefathers?  Inwardly, I wonder the same thing myself.  All around me, their eyes peer into mine, and I cannot help dwelling upon their unspoken accusation, echoing in my mind. 

Silent, I turn and make my way toward the rear glass doors where, outside, stands a large, wooden “sandbox,” covered to protect visitors from the hot sun and rain.  Excavation tools line the structure, and a sign encourages onlookers to dig in the sand to find bones which are hidden below the surface.  I take up one of the tools and begin scratching in the sandy soil, and a couple of minutes later, I find my first “treasure,” a bone which the overhead display informs me is the leg bone from a modern, indigenous bison.  If excavation was only this easy . . . I think to myself.  Still, anticipating the overwhelming desire for guests to retrieve a memento or two from their travels, those in charge of the interactive display have wired the bone to the bottom of the sandbox, effectively securing the treasure.  No souvenirs this day.

After this, the trail down into the heart of the excavation divides in two, and I choose the path on the right, since it seems, as Robert Frost might observe, “grassy and wanted wear.”[1]  It’s an early July day, and I find myself wiping perspiration from my brow as the sun plays tag with the scattered clouds above.  Multi-colored, slender, solitary wasps buzz haphazardly among the yellow and purple wildflowers that shoot up here and there.  The wind continues to blow.

Within seconds, though, I am pleased by my choice.  Like slender green and yellow arrows shot from a bow, little lizards dart across the narrow trail, parting before me with each step I take.  Their movement, fluid though it be, is eclipsed by the multitudes of mottled brown, green, and golden grasshoppers springing into the air everywhere, some landing on my bare legs, shoes, and clothing.  I wave a few off the more ticklish parts of my body, and for this effort, some leave me a parting gift: brown, juicy, and pungent.  I cannot blame them, though, for adhering to millions of years of evolutionary instinct.  How are they to know I am not some insectivorous predator crawling along the trail intent on capturing and eating them?

As I continue my trek, I am once again amazed by the variety and beauty of plants all around me.  The grass here is thick, and should I deviate from the trail by only a few inches, any number of hooked, spiny hitchhikers may stowaway on my clothing.  Although I have walked among grasslands in both the Midwest and the Great Plains, I never cease to be awestruck by the natural beauty, the plant and animal life, that defines my home.  Millions of years before the first humans set foot upon these grassy slopes, animals as large and as varied as any in Africa roamed the North American plains, nearly all of them come and gone: extinct.  Now, here roams another species, bipedal, not hoofed, yet altogether as dependent upon its environment as any creature that ranged across the prairies, itself a product of natural selection on some grassy, East African savannah just a couple of million years ago.  What will be the cause of our extinction, I ponder as my steps lead me to a scenic lookout at end of the trail.

Peering across the not so distant valley, I notice for the first time orange flags that stand at intervals across the cliffs on the opposite side of the ravine.  They appear to mark something of apparent importance that I have yet to discover.  From this vantage point, though, I have a clear view of the land just below the dig site.  A brown wooden railing runs the length of the site across a gulf that drops off several dozen feet or more, and at the end of the walkway is a large covered structure called “the Barn” which I decide to visit next. 

Returning to the top of the divided trail, I take the left branch this time, and within moments, I am walking along the wooden platform mounted parallel just above the excavation site.  I stop for a moment to pick off errant cockle burrs from my socks that have been pricking my ankles before moving toward the most current dig.  Several fossils jut from the ground, and small white placards inform travelers what each item is and its approximate age.  I am compulsive about reading each sign, desiring to miss nothing along the way.  One sign informs the traveler that the volcanic ashbed here is eight foot thick while another indicates that the ashbed across the valley is only one foot thick.  Now I understand the significance of those bright orange flags. 

Standing still for a moment, waiting on other travelers ahead of me, I peer around the hilly landscape, trying to envision what the prehistoric prairie would have looked like.  A sign along the path says “12,000 years ago” and lists a number of animals that went extinct.  The thought is discouraging.  In my mind, images of mammoths, tiny horses, giant beaver, sabercats, mastodons, dire wolves, and giant sloths fill the land, hunting and eating, chasing and fleeing, teaching young that would one day pass along the rich genetic heritage of their species, of all life.  It’s a tenuous, often bloody, balance - brutal yet as beautiful as anything we see in nature today.  And then it all came to an end during the last Ice Age 12,000 years ago.  With the expansion of semi-nomadic humans across the Bering Straits, came the demise of all of these animals.  What nature alone had not done, we did.

Again, dust swirls in the wind, and I rub tears from my eyes, though not, perhaps, from the dust alone.

Over ninety-nine percent of species that have ever lived are now dead, extinct.  And a sizeable number of species alive today are at risk of extinction due to the cultural, political, and economic choices we homo sapiens are making.  We are very likely the first and only species on this planet to contemplate the “big picture,” to imagine our purpose and place in the web of life.  Yet so many worry only about the here-and-now, the pragmatism of daily existence, that few of us rarely stop to ask ourselves if we are squandering our natural inheritance.  In sacrificing our genetic brethren in search of more food, more fuel, more profit, are we heading towards our own day-of-reckoning?

The wind subsides, though my thoughts won’t dissipate quite so easily. 

Just below, a man in a wide-brimmed hat, blue jeans, boots, and a white shirt is concentrating on chipping away, then dusting something in the hardened, gray earth.  His beard nearly matches the color of the ash.  I stop short, waiting for the family ahead of me to move on before approaching the end of the deck-like platform just above the man.  He is intent, quiet.

Not normally at a loss for words, I find myself searching for something to say.  He appears oblivious to my presence.  This is not the Hollywood paleontologist from Jurassic Park, I realize, after a couple minutes of silence.  This is the real thing, and I suddenly find myself secretly envious of this man, obviously enthralled in every minute detail of his work.  No, I think to myself, not work, but something altogether different.  Passion.

I recall when I used to have that kind of “passion.”  As a child in the 1970s, I used to play with my plastic dinosaur toys for hours at a time, compelling my mother to take me to the library each week where I would check out children’s books on prehistoric life.  I would avidly read, then act out what I had read, fascinated by all ancient life.  It was no wonder, then, when my passion grew and came to envelope birds, too.  The later revelation that these winged visitors of my birdfeeders were the living descendent of dinosaurs only further fueled my passion, a passion that time and adult cares and worries had all but smothered.  Now, watching this man, I see what might have been . . . I see me.

“Hi,” I finally interject.  The man hardly looks up at me.  “This is quite a site, here.”

The man nods, still sitting on the ground.  He begins to explain that he is excavating another fossil, but it seems rehearsed, as though he has said this not a few times.  Possessing a rather modest, layman’s knowledge of paleontology, I decide to take another tack;  I had read nearly all of the signs posted here and in the Center, so I engage him on a more detailed level of conversation.  I am glad that I did.

I discover much about the cause of the great animals’ death, why some species held on to life longer than others did, and what the flags across the valley signified.

“That’s the same level where we’re standing now,” the ruggedly-built man explains more eagerly.  “The ash is about one foot over there.  It’s about eight foot, here.”

“Why the difference?”

“It’s deeper here because in the Miocene, this was the lowest elevation in the area – this was the valley.  Ash blew around and settled in the lowest part of the valley.  This was the water hole.”

It took a special type of anatomy to digest the tough, hardy grasses, but nature didn’t take too long in meeting the challenge.  Thus, with the advent of grasses came the explosion of hoofed mammals, or ungulates, evolved specifically to graze on this new group of flora.  And few places in the world can boast a more impressive array of ungulate fossils than here in north central Nebraska.  Ancient, unique, and often queer species of horses and camels, rhinos and rodents, deer and dogs lie scattered across what was once an ancient watering hole when, about twelve million years ago, a  now extinct volcano in southwest Idaho erupted, dropping ash for millions of square miles across the continent.  In the fallout, blowing and drifting ash accumulated on these grasses, and for the next several days, grazing animals inhaled this dust, filling their lungs with deadly, abrasive powder.  Smaller animals were the first to go, many within hours; then, after a few days, the large horses and camels, followed by the largest animals of all, the rhinos.  Within little more than a week, all were dead, their rotting, dessicated bodies piled in and around the ancient watering hole we now know as Ashfall. 

Today, all I can smell is the scent of grass and excavated ash.  Still, it is an ancient burial ground as sacred to me as any human religious site.  These animals are more than mere fossilized corpses; they are nature’s genetic heritage: our family.  I wonder, too, if I am the only one who feels this way. 

After a little more chatting, I can see he has work to do, so I gratefully bid him goodbye.  The man returns to his work.  Each brush stroke he makes is deft, deliberate.  It reminds me of a great sculptor, seemingly forming the stone lying beneath him with his very hands.  It is in this very moment that I am aware that I am not the only one who reveres this hallowed ground, and I begin to wonder, who is this fellow sojourner into the Great Plains’ past.

“Oh,” I added, almost as an afterthought.  “By the way, what’s your name?”

Hardly stopping from his work, he answers, “Mike Voorhies.”  I recall the name from placards inside the Center and suddenly understand his reverence for this site.  Dr. Voorhies is a professor in the geology department at the University of Nebraska at Lincoln and the man who discovered this paleontological treasure.  This place is, in a way, his legacy to us all.

When I finally arrive at the last stop along the trail, the Barn, I stand still, eyes scanning the bone-white ground.  The scene is heart wrenching.  Rising from the ash like shadowy, snow-capped mountains lie dozens of fleshless rhino skeletons, their bones hardened into rock.  Among them and exposed in the layer just below are the skeletal remains of horses.  And below these lie countless smaller animals whose bones are present though mostly unseen.  In this part of the water hole alone, dozens of animals, hundreds maybe, had perished in only one week twelve million years ago.  Others must feel the solemnity of the site, for voices are low, hushed, as travelers speak to one another, taking photos of an aftermath that only carnivores and other ancient scavengers would have lived to witness.  As the modest crowd dwindles, I meet Brad, an undergraduate paleontology student from the University of Alberta, Canada, and speak with him awhile.  With an unsettling exuberance, he acknowledges the impact of the tragedy we are witnessing here, and, as I turn to make my way back to the Center, mentions something I had never quite considered.

“You know, if you think about it, this is probably the most morbid job anyone could have.”

I stop and turn, tilting my head while peering inquisitively at the young, bespectacled scholar.

Perceiving my puzzlement, he explains.  “We spend all day digging up dead bodies and really love it.  That’s kinda’ morbid, isn’t it?”

I smile and nod, wishing I could have more than a mere onlooker’s share in this morbidity.  I wonder, too, what beings – standing here million years from now unearthing our own bones – will have to say about us: creatures of the grasslands.  How will we be remembered, or will we even be remembered at all? 

As I make my way back over the trail and toward the Center, I stand for a few moments outside the facility, scanning the rolling hills along the grassy horizon.  The wind buffets my body, and for a brief moment, I hear something, a cry perhaps, though whether it’s from the raptor circling overhead or echoes from an earlier epoch I cannot be certain.  Yet I know one thing: I, too, am a product of the grasslands.  I can answer the unspoken challenge, now, of countless generations of Great Plains creatures.  My heritage is not different from theirs.  Our heritage is one.