DUBOIS, WYO. —They found the first bit of evidence before they left the parking lot. Flakes of rock and arrowheads littered the ground, easily missed by the casual observer but striking signs of prehistoric life to the trained eye.
Students from Central Wyoming College were buoyed by their finds on the 25-mile trek from a trailhead outside Dubois to the edge of Wyoming’s biggest glaciers. But then, at the top of the state, where harsh winds blow away deep snow and temperatures are often frigid, they discovered something none of them expected: a bison jump.
More specifically, the highest elevation bison jump ever recorded in North America.
“The conventional wisdom 30 years ago was that Indians didn’t go into the mountains,” said Todd Guenther, a professor of anthropology and history at CWC who helped uncover the jump. “Now Wyoming researchers have documented that yes, indeed, they did go in the mountains and spent a lot of time there and lived a pretty good life.”
The group discovered the jump as part of CWC’s new Interdisciplinary Climate Change Expedition, which takes students into the Wind River Range to study the mountains’ rapidly shrinking glaciers and their relationship with humans past and present. Guenther will discuss their archaeological findings Thursday at the Buffalo Bill Center of the West in Cody.
Guenther knew the group of students would find signs of prehistoric life. His field school went in armed with a Forest Service archaeology permit planning to survey ancient campsites identified by past groups.
When they reached the toe of the Dinwoody Glacier, they began to find campsites dating back to 11,500 years ago.
“What we have is this continuous record of human presence at high elevations — 10,000, 11,000 or 12,000 feet above sea level,” he said. “It goes back to the first people who inhabited North America.”
The group stumbled on signs of the bison jump — a cliff or precipice where native peoples drove the animals to their deaths — toward the end of their first session in the summer of 2015, said Morgan Robins, a Lander students now studying at the University of Wyoming. They found countless cultural material – arrowheads, stone tool fragments and hunting blinds – and then followed the material down to the Burrow Flats area for continued reconnaissance.
“Another student found a cairn and then found another and another and followed it until Todd and the other student hit a precipice and that’s when it hit Todd that it was something way more than they originally thought,” Robins said. “They went down into the possible butchering area and saw all the flakes and Todd realized it was a bison jump.”
Lichen growth on the cairns – or rock towers – helped prove they were prehistoric.
The line of stacked cairns was about a mile long, and was dotted with hunting blinds where early people hid and pushed the animals forward, Guenther said.
Two shaman structures, which were holes in the ground surrounded by stones, rested near each end of the drive line. People used the pits to pray to spirits for a successful hunt, he said.
At the bottom of the precipice was an area with thousands of stone artifacts.
“It’s where we suspect the animals were butchered and processed,” he said.
Discovery of the bison jump is also helping solidify a theory of Guenther’s: early people lived at high elevations throughout the year. Up until now, most scholars believe early humans spent summers in the mountains and winters below in the plains.