At the end of the last ice age, 13,000 years ago, Earth went through one of the most extreme periods of global warming ever experienced by humans. In the San Juan Mountains, enormous tongues of glacial ice that had spilled out over the land for tens of thousands of years suddenly shrank, and the mesa and plateau lands of the present-day Four Corners country dried out, transforming into high desert.
At that time, the largest of the great ice-age mammals that patrolled this region – the woolly mammoth, the mastodon, the giant ground sloth, the saber-toothed tiger, the North American camel – also disappeared. And vanishing with them were the ways of life of the people who lived here whose specialized craft was hunting those intimidating creatures
But those people left behind their story in small, hard-to-find, and fragile bits of their lives.
This summer, the Fort Lewis College Archaeological Field School spent six weeks at a remote site in southwestern Colorado uncovering and piecing together that story -- and other stories buried there by the many more-recent peoples, all the way up to the present, who have occupied and made use of the same places and spaces as those ice-age residents.
These undergraduate researchers also documented a modern-day crime story that ties all those eras together.
Our work here is really going a long way toward helping the BLM and other public land managers in the area understand the scale of the looting, and work in the future to combat it to benefit all of us.
Jesse Tune, assistant professor of Anthropology
“The Archaeological Field School is one of the gems of the Anthropology Department at Fort Lewis,” says Jesse Tune, assistant professor of Anthropology and director of this summer’s field school. “It allows students to go out and actually do archaeology in a hands-on environment. And then we bring all of that material back to the college and use it in classes and student research.”
The Archaeological Field School is held every summer at different locations around the culturally-rich area surrounding Durango’s Fort Lewis College, varying year to year, or sometimes settling into a single site for several consecutive summers. Students spend five to six weeks working and often living in the field, honing their classroom- and laboratory-learned skills by doing original primary research.
The 2019 field school was situated up an isolated, shallow side canyon in Disappointment Valley, near the wilderness of the Dolores River and close to the Utah border. Long, gently sloping slabs of crumbling slickrock line the canyon rim. Vegetation is sparse and stands in contrast to the rock that dominates the landscape -- bursts of green piñon and juniper trees, blueish sage, and the dry brown of shrubs and grasses evolved for the harsh terrain.
“This summer we started a new project in collaboration with the BLM,” Tune explained at the camp in the early-summer heat of June. “We're excavating several sites, including a 13,000-year-old Clovis site. Clovis is the earliest archaeological culture in North America, and where we're working is one of the oldest archaeological sites in Colorado and the Four Corners area.”
“We use traditional archaeological methods -- trowels, brushes, and such -- as well as a pretty intensive drone survey and mapping operation,” he adds. “So the students are getting training on some really cutting-edge methods.”
In addition to hands-on archaeology, though, the Bureau of Land Management, which manages the public lands where the site resides, has also given Tune and his team of nine Anthropology majors a special task: examine and document the damage to the prehistoric record inflicted by recent illegal excavating at the ancient site.
As it turned out, that damage is extensive.
“This rock shelter has been looted illegally by some people digging for antiquities, probably in the last ten to fifteen years,” described Tune. “We and the BLM thought that the looters had spent just a couple of days here and dug a few pits. Now it looks like they did a pretty good job of destroying the site. We even found cigarette butts, gum wrappers, and plastic straws just sitting right on the bedrock at the bottom of all of the sediment.”
Fortunately for archaeologists, in these thieves’ desperation for artifacts of commercial value, they often discard what's most important for the archaeological record – items that aren’t just pretty, but that reveal what people were actually doing in the deep past. For that, it’s often the stuff those ancient residents threw away, such as discards from making stone tools and spear points, that researchers can use to link their activities to the environment and setting.
“Probably the oldest artifact that we've found out here all summer is a projectile point dating to somewhere around 13,000 years ago. While we can't date that directly, the reason we think it's that old is how it's made, the overall shape of it, and how individual flakes were taken off of it,” Tune explained. “So this particular artifact is really exciting for us because it’s one of the oldest artifacts in the area that we're working, and it's really representative of the earliest archaeological complex in North America with Clovis technology.”
On that bright blue June day, after more than five weeks in the backcountry, the field school teammates were still busy. Students worked the carefully flagged ground with hand tools under the shade of the overhanging rock shelter -- which is why the ancient people set up residence here in the first place, as it provides shade from the high summer sun while in the winter letting in the warmth of the low-angle solar rays. Other students broke up clods and chunks of sediment with a swinging suspended sifter. Still others used a laser to aid with later recording of the exact distributions of their discoveries in a computerized 3D geographic information system map of the site.
“We’ve gotten some snow, some rain, and some heat now,” laughed senior Anthropology major Courtney McCarthy. “But it's been good being outside all this time. This field school has given me a lot of tools that I can use in the future, as well as a well-rounded knowledge of what the field actually includes. I like looking at the materials and trying to figure out how they were used and what people were doing back in the past.”
Much of that figuring out of those ancient stories will be done later, back at facilities at Fort Lewis College, by the field school participants and other students in the Anthropology program.
“All of the artifacts that we're collecting this summer are going back with us, and we're going to spend the next year cleaning, processing, analyzing, and writing up a report on everything that we have here,” said Tune. “So while this is really just one summer class, the results of these six weeks are actually going to be used in multiple classes down the road. And some of these students will end up using the artifacts and data we're collecting as part of their senior research projects.”
In addition to the artifacts they found and catalogued, the students’ work documenting the methods, scope, and scale of the looting that the Disappointment Valley site has suffered will also aid in the fight to protect other cultural resources around the region from illegal pillaging.
“While on the one hand, it’s disappointing that a lot of the materials and sediments that we found were displaced and jumbled and mixed, it's actually significant that we spent our summer out here documenting this,” Tune said. “The people who did this got caught this time, fortunately, but that is not what typically happens. It's very difficult to catch illegal looting. So our work here is really going a long way toward helping the BLM and other public land managers in the area understand the scale of the looting, and work in the future to combat it to benefit all of us.”