Archaeologists working in the borderlands of northern Mexico have uncovered a camp used by ancient hunters as much as 10,500 years ago, revealing insights into some of the earliest human history in the Greater Southwest. On a ranch near the Santa Maria River in northern Chihuahua, researchers have unearthed more than 18,000 artifacts, including thousands of stone flakes, cores, and hammers, along with 370 projectile points, and a dozen stone ovens. But the most surprising find has been the grave of a teenage girl, who was interred among the rocks, alone and unadorned, some 3,200 years ago.