IT has been centuries since anyone understood what all the elaborate faces, swirls, lines, and dots mean on the Mayan ruins stretching from eastern Mexico through Belize, Guatemala, Honduras, and El Salvador. The ancient Mayan civilization reached its pinnacle around AD 800. Great religious and political centers were built at places like Chich'en Itz'a in Mexico, Tikal in Guatemala, and Cop'an in Honduras. Art and agriculture flourished. The Maya were keen observers of the heavens and developed complex calendars and dating systems based on positions of the sun, moon, and stars.
Then, for reasons that are still not certain, the magnificent monuments were abandoned, the pyramids sank beneath the forest canopy, and the Maya returned to a subsistence-level existence. By the time the first Spanish explorers reached the Americas in the 15th and 16th centuries, the Maya had been subjected by other groups and the Aztecs were calling the shots in Mexico.