Surprise! Ancient Mayans shopped for food

BEIJING, Dec. 4 (Xinhuanet) -- Archaeologists didn't think Mayans did it, but chemical residues discovered in soil from Mexico's Yucatan peninsula suggest the ancient civilization traded food in marketplaces.

Archaeologists studying Mayan cities have long recognized that the cities were home to more people than the local agricultural capacities could have supported, said Shepherd University archaeologist Bruce Dahlin, who led the new study of the Yucatan soil.

For many years archaeologists looked for evidence of advanced farming practices that could have increased agricultural capacities, thus sustaining the populations. The idea that Mayans might have imported food and other goods wasn't taken seriously because most archaeologists thought the Maya elite had a system whereby underlings were paid for loyalty by goods passed down the social ladder.

But large, open areas found in settlements of the Classic era (about A.D. 300 to 900) looked similar to marketplaces, although archaeologists could find no strong indications of the areas' purpose.

Dahlin brought in environmental scientist Richard Terry of Brigham Young University and his team to analyze surface soil samples from Chunchucmil in the western Yucatan for signs food had once been there. These indications come in the form of phosphorus, left in the soil by decomposed food.

"All food materials contain phosphorus, and a common denominator of all humans is that they bring food to places where they live," Terry said. "Over time, the organic matter is ground into the soil and rots, but the phosphorus holds to the soil particles even in a tropical rain forest that gets a meter or two of rain every year."

Terry and his team found concentrations of phosphorous up to 40 times higher in these open areas than those in ancient patios and streets. The pattern of phosphorous residue matched that found in the last remaining modern market that runs atop soil (all other modern markets have been paved).

The matching patterns indicate the Mayans did have a market economy, and studies from other sites may reveal just how far that economy may have spread. The team's results are detailed in the journal Latin American Antiquity.

(Agencies)