NATURE NOTES:
In the Lower Pecos, New Research on a 13,000-Year Record of Texas Prehistory

By Andrew Stuart

Nineteenth century Americans knew the Pecos River as the boundary of the West. And the westering traveler today can feel that transition. In the canyonlands at the confluence of the Pecos and the Rio Grande, the Hill Country gives way to the Chihuahuan Desert. Mountains appear on the western horizon. Ocotillo and yucca stud a harsh landscape.

These canyonlands of the Lower Pecos are also a world-class archeological site. Caves and shelters here preserve one of the richest records we have of hunter-gatherer life in North America. Now, a group of Texas archeologists is taking a new look at that 13,000-year record.

A half-mile from Langtry, Texas, Eagle Nest Canyon is luminous in midday light. But along the canyon’s bright limestone walls are pockets of shadow – natural rock shelters, shallow caves, carved into bedrock.

As shade, as storage for firewood, tools and food, the shelters drew nomadic peoples. And because they’re dry, the caves preserve traces of those societies – in fibers and food remains, in stone and pigment. It’s this preservation that sets Lower Pecos archeology apart.

Dr. Steve Black, of Texas State University, leads the Ancient Southwest Texas Project, an ambitious reevaluation of archeology here.

“In the Lower Pecos, because it’s a dry area anyway, and because there are big rock shelters, the evidence is preserved,” Black said. “So that’s what’s unique about the Lower Pecos Canyonlands, is that the evidence is so well-preserved.”

The shelters’ deepest deposits contain bones of mammoth and Ice Age bison, and the tools of Ice Age hunters. Later, Native peoples baked plants, butchered deer, filleted catfish. And they created paintings on the limestone walls.

The region is best known for its intricate murals, of the Pecos River Style, created between 4,200 and 1,500 years ago.

Early excavations targeted artifacts – items for museum display. In the 60s, archeologists searched for stone tools. Black has assembled archeologists from across the state, from a variety of sub-disciplines. Rather than artifacts, they’re after information, Black said.

The slopes below several shelters are covered in fragments of burned rock. It’s evidence of the ancient practice of earth-oven baking.

Here, people buried the hearts of lechuguilla and sotol among heated rocks. In the “slow-roasting,” the otherwise inedible plants were converted into food.

Analyzing fire-cracked rock, Black and his colleagues find that some earth-oven sites were used as many as 2,000 times. Plant-baking appears to have increased over time. It was labor-intensive. Black hopes for new insight into this increased use of plant-baking.

“It’s a very energetically costly way to make a living,” Black said. “So the question is, Why would people go to so much trouble, expend so much energy on a meager return? The short answer is, because they had to.”

The shelters also preserve spiritual and creative dimensions of ancient life. In work on White Shaman Cave, archeologist Carolyn Boyd makes a powerful case that its rock-art mural represents a creation narrative. “Dirt” archeologists have often been skeptical of rock-art interpretation. But in the new project, Black has partnered with Boyd’s rock-art center, the Shumla Archaeological Research and Education Center. The partnership, Black said, can produce a richer understanding of ancient life.

“So these place weren’t just for putting sacred imagery up on the walls, or recording their belief systems in that way, nor were they just for baking plants for food,” Black said. “They were part of the same thing – life.”

Black said shelters may have been sites for making alcoholic beverages from sotol and lechuguilla – as a “social elixir” and an element of ritual. New research could confirm that. The team has unearthed “quids” – fibrous remains of sotol and lechuguilla, discarded after the sweet “meat” of the plants was eaten. DNA from the quids could shed light on the genetic relationships among prehistoric peoples.

The Lower Pecos is a remote region. Despite its remarkable preservation, it’s been at the fringes of research.

“Part of the reason that this was not more widely recognized is because it was in the periphery,” Black said. “It’s in the periphery of the American Southwest. It’s in the periphery of Mesoamerica. And it’s peripheral to where major research interests were – and are – for most North American archeologists.”

In the Ancient Southwest Texas Project, this unique window into prehistory is getting the attention it deserves.