Carolyn Boyd guides her pickup down a cliffside trail overlooking Dead Man's Pass, a limestone canyon cut deep into the backcountry of southwest Texas. A ring of black vultures circles overhead. Boyd slows the truck and scans the canyon for what has drawn their interest. On top of a boulder, splayed out like a ritual sacrifice, is a half-eaten goat carcass. “Mountain lion,” she says.
The region known as the Lower Pecos is an arid 21,000-square-mile expanse of southwest Texas and northern Mexico surrounding the confluence of the Pecos River and the Rio Grande. The land is barbed with cacti, teeming with rattlesnakes, and riven with impassable canyons. But more than 4,000 years ago, these barrens were home to a flourishing culture of hunter-gatherers, creators of some of the world’s most complex and beautiful prehistoric rock art. The literal meaning of those paintings had been dismissed as an unsolvable mystery—until ...
