Much of what we know about past civilizations in Mexico comes from the writings of colonial Europeans -- Spanish conquerors and priests -- who arrived in the Americas in the 1500s. But archaeological evidence from recent excavations at a site called El Palenque in the Valley of Oaxaca, Mexico, shows that temple precincts similar to the ones the Europeans encountered had existed in the region some 1,500 years earlier.

Married archaeologists Elsa Redmond and Charles Spencer, both of the American Museum of Natural History in New York, reported the discoveries Monday in the journal Proceedings of the National Academy of Sciences. 

Redmond and Spencer have been studying the remains of ancient civilizations in Oaxaca since the 1970s, when both were undergraduates at Rice University. Interested in learning how early states arise, they have been working in the area around El Palenque since 1993. The research they described in the new paper was initiated 15 years ago at the eastern edge of the site, where three symmetrically aligned, multiroom temples faced a public plaza. Behind the temples stood two residences that the archaeologists believe were used by priests....