Apparently caught between two cultures, the 2,700-year-old pyramid in Chiapa de Corzo (map), Mexico, may help settle a debate as to when and how the mysterious Zoque civilization arose, according to excavation leader Bruce Bachand. At the time of the pyramid tomb's dedication, hundreds of artisans, vendors, and farmers would have known Chiapa de Corzo as a muggy town, redolent with wood smoke and incense. Above them towered the three-story-tall pyramid, a "visually permanent and physically imposing reminder" of their past rulers and emerging cultural identity, said Bachand, an archaeologist at Brigham Young University. The two rulers found with the...