At the time of the Lewis & Clark expedition, scientists (then often called natural historians or natural philosophers) were just beginning to unravel the fossil records they found scattered at their feet. William Clark’s brother, the military hero George Rogers Clark, happened to live at one of the richest deposits of fossils in the United States at the Falls of the Ohio near Louisville, and had developed ideas years ahead of his time about the warm ocean that had once covered Kentucky and Indiana. Likewise, Lewis’s mentor Thomas Jefferson collected fossils sent to him by G.R. Clark and others and avidly corresponded with scientists all over the world about ideas that were then radical, such as evolution and extinction.
Lewis and Clark themselves had both participated in digs at the fantastic Kentucky site called Big Bone Lick, where dozens of skeletons of Ice Age mammoths and mastodons had been discovered. So it was no surprise that when Thomas Jefferson conceived the westward expedition, one of the things he asked Lewis and Clark to do was look for fossils. (He even held out hope that creatures such as woolly mammoths might still exist in the unknown West).
Like many of Jefferson’s edicts, the mandate proved difficult to carry out under the pressure of keeping the expedition on the move. Lewis and Clark did make several fascinating finds, including the 45–foot-long backbone of a “fish” (later determined to be a pleisosaur). But it would remain for later generations of paleontologists to discover that Nebraska and the Dakotas were among the world’s treasure troves for prehistoric fossils.
Excited to see for ourselves, we had a great breakfast of eggs and biscuits and gravy at the hotel buffet, bagged a picnic lunch, and headed out west on the beautiful ribbon of highway known as Nebraska 20. A few miles out of Sioux City, the landscape transforms into a splendid fantasy straight out of a Grant Wood painting, with gently rolling green hills covered with a lush patchwork carpet of cornfields and soybeans and dotted with silos, red barns, and rambling farmhouses. During our two-hour drive to Ashfall Fossil Beds State Park, we encountered very little traffic and passed through only a few very small towns.
Ashfall Fossil Beds is the site of a local apocalypse. About twelve million years ago, a huge volcano in what is now southern Idaho erupted, spewing an enormous plume of ash over a huge swath of North America. It was just one of many such explosions in the history of this planet. But for the residents of this little patch of present-day Nebraska, it was the end of the world.
Here was a waterhole that drew all the local forms of life. Mammoths came to drink here. So did rhinos, three-toed horses, small camels, majestic cranes, saber-toothed deer, and bizarre predators called bear-dogs. When the ash came, the animals sought refuge at their beloved waterhole. The birds were the first to die. Others, like the rhinos, lingered for days. Finally, the local creatures passed into the ruins of their old world and were covered by the ash, preserved and forgotten like the citizens of some prehistoric Pompeii.
In the 1970s, a paleontologist found a rhino jawbone on a Nebraska farm. His discovery led to the discovery and continuing excavation of this amazing site, now a state park. Ashfall Fossil Beds is set up for visitors with an interesting visitor center and a lab where you can see the progress of work being done by Nebraska students. But the big attraction is the Rhino Barn, a structure built to enclose an amazing array of fossilized skeletons lying where they fell. Rhino mothers lay next to babies. Horse bones lay scattered by scavengers who themselves would soon die.
The Ashfall Fossil Beds park is fun and fascinating for anyone with an interest in our prehistoric planet, but it is more than that. Seeing this place has far more impact than seeing a fossil in a museum case. For the first time I truly grasped that creatures come, have their day in the sun, and go on, never to be seen again on this old world. I hope there is someone around to puzzle over our bones, millions of years hence.
At the picnic shelter, we met a cute pug out out on his first-ever car trip! We had a nice picnic at the beautiful park — lots to talk about here!