Vanishing Act

To European explorers who dared to venture up southern New Mexico's Rio Alamosa, the rugged, narrow valley earned the nickname Salsipuede - "leave, if you can."

Yet the region's apparent lack of hospitality didn't deter everyone. Early in the 13th century, a band of newcomers entered the valley, spotted a 115-foot tall volcanic butte in the middle of the creek, and decided to call its summit home.

In June, archaeologist Stephen Lekson and a pair of graduate students conducted the first detailed excavation of ruins atop the butte. What they've found may help rewrite the final chapters in the history of the Southwest's most alluring prehistoric culture - the Anasazi. From a political center at Chaco Canyon in northwestern New Mexico, the Anasazi extended their social and economic reach over a broad section of the Southwest roughly centered on what today is the Four Corners area.

Chaco Canyon's heyday ran from about AD 850 to 1130. As Chaco Canyon's star waned, other famous Anasazi pueblos emerged, including Aztec, just north of Chaco Canyon, and Mesa Verde in southern Colorado. But by 1300, the Anasazi vacated the Four Corners in one of the most unusual mass migrations ever.

"The current chamber-of-commerce take on this is, 'The mystery of the Anasazi: Where did they go?' " says Dr. Lekson, sitting in a tiny office at the University of Colorado's Museum of Natural History, where he is curator. "You talk to Pueblo people today and they just laugh. They'll say, 'We'll show you a road map, and show you right where they are; they're us.' "

But the details of the migration - even whether the sudden evacuation took place at all - have been the subject of heated debate among archaeologists who focus on the Southwest. Today, Lekson explains, the "received wisdom" is that Anasazi clans moved south into areas that became today's pueblos, ranging from the northern Rio Grande in the east to the Zuni and Hopi to the west. There, they were absorbed into existing cultures.

The site along the Rio Alamosa, known as the Pinnacle Site, suggests a different story - that large numbers of Anasazi kept heading south, perhaps as far as northern Mexico. There, at Paquime (now known as Casas Grandes), Lekson holds that the Anasazi elite stopped to make what would be their final attempt at reestablishing a capital, as Chaco Canyon and later Aztec had been.

The Rio Alamosa region hosts several important sites and likely formed a rough boundary between several key Southwestern cultures, notes Georgia State University anthropologist John Kantner.

Three of these sites, including Pinnacle, are the subject of a larger research effort under the aegis of Human Systems Research Inc., a private, nonprofit archaeology center in Las Cruces, N.M., and the Caada Alamosa Institute, another non-profit organization founded by Dennis O'Toole, a retired museum director who owns the ranch on which the ruins sit.

Lekson and his colleagues weren't the first to find Pinnacle; it had been noted decades before, but was misplaced on maps. In 1988, Lekson and two interns found it again as they hiked along the lower Rio Alamosa as part of a larger archaeological survey.

"It was on the last day of the season," Lekson recalls, when he and the interns were walking upstream. "They were fussing about something, so I sent them on one side of the creek. All of a sudden, the bickering stopped, and they hollered across the creek. There was this great big plaza pueblo, nothing like anything else you'd ever see down there."

Last year, one of Lekson's colleagues, Karl Laumbach, with Human Systems Research, conducted a training "dig" that turned up pottery pieces whose patterns and glazes were close kin to those first seen at Mesa Verde.

In June, Lekson and his colleagues spent two weeks taking a closer look. Hoping to find a family trash dump, or midden, the team unearthed "one of the nicest middens I've seen in a long time," he says. That was another strong clue that the inhabitants came from the north, because cultures in Pinnacle's general vicinity tended to spread their refuse around the countryside. The team also uncovered a wooden ceiling post, whose tree rings could be used to verify the site's date. And the pueblo hosted a section of exposed wall "built with very nice masonry that you don't see down here, but you see at Mesa Verde a lot," Lekson adds.

Ironically, while Pinnacle could prove to be the keystone in a case for Anasazi migration deep into southern New Mexico, it isn't the first such site. During the 1970s, an enormous, 500-room ruin at Gallinas Springs, 12 miles northwest of Magdalena, N.M., turned up pottery initially identified as Mesa Verdean.

"Very seldom do the archaeology gods give you an easy one like this," Lekson says. Yet different research teams disagreed on whether the pottery pointed to Mesa Verde Anasazi or a more local culture.

In 1983, Lekson worked a site at Palomas Creek, 78 miles south of Gallinas Springs, whose pot pieces bore a striking resemblance to the Mesa Verde-like shards at Gallinas Springs. Again, the site suggested a southern migration. Add Pinnacle, which sits roughly between the two earlier discoveries, and "the third time's a charm," Lekson says.

Combined with a half-dozen sites around Tucson that point to a deep-southern migration from the Four Corners area into southeastern Arizona, Pinnacle, Gallinas Springs, and Palomas Creek could rewrite the history of the Anasazi migration, Lekson holds.

Archaeologists haven't "come to grips" with the Arizona sites, he says, and now the three large sites in southern New Mexico "are showing the same pattern." They stand in stark contrast to sites inhabited by people already living there, "and they're hundreds of miles from where [Anasazi remnant groups] are supposed to be."

It may be that the 150-room pueblo at Pinnacle was built to support a migration stream heading south along what Lekson has called the Chaco Meridian, a line that runs south from Chaco Canyon and Aztec pueblos to Paquime in northern Mexico.

Pulling together various lines of evidence, Lekson holds that the evacuation of Four Corners was essentially a political decision taken by elites who first turned due north from Chaco Canyon to Aztec, then turned and headed directly south when the new capital at Aztec ran into the same food and resource constraints that shut down Chaco Canyon.

By holding to the same meridian, the elite could claim a symbolic linkage to the good old days at Chaco Canyon.

With the enthusiasm of June's discovery still apparent, Lekson notes that archaeologists have been working in the Southwest for 120 odd years. "You'd think we'd have this all figured out by now. It's fun to stumble onto an important ruin that essentially has been unknown to science."

(c) Copyright 2000. The Christian Science Publishing Society