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A Flood of Evidence

Jeffrey Wilkerson studies how ancient people thrived in the lowlands of Mexico's Gulf Coast. He believed that inundations occasionally wiped out cities, a theory supported by a huge storm that almost killed him.

November 16, 2000|CHRISTINE McDONALD | SPECIAL TO THE TIMES

GUTIERREZ ZAMORA, Mexico — Archeologist Jeffrey Wilkerson had long suspected that massive floods flashed through Mexico's Gulf Coast lowlands every few hundred years, overwhelming ancient pre-Columbian cities and their sophisticated flood control systems.

But not until he was nearly swept away in last October's Tropical Depression No. 11 did Wilkerson get to glimpse the destructive force of these storms.

After his rowboat capsized, he spent two days clinging to a mandarin tree as the cold, frothy flood waters swirled around him, carrying an estimated 400 people to their deaths and leaving thousands homeless.

Once the water subsided, silt and rubble littered what was left of the field station. Part of his office building--which had once looked out over 300 feet of botanical garden--had crumbled and fallen into the Tecolutla River. Libraries and laboratories were swept away along with microscopes, photography and darkroom equipment, computers, video cameras and collections of old textiles and historical documents.

A year after the storm hit, Wilkerson is still mired in reconstruction work but has turned a personal tragedy into professional inspiration.

Today, he is observing modern man's efforts to adapt to conditions he believes may have destroyed El Pital, a "flowering metropolis" that dominated Veracruz's Gulf Coast from about 300 BC. Just as last fall's storm sent residents fleeing, Wilkerson thinks another massive storm may have abruptly ended El Pital's reign.

"We know that at or very soon after El Pital's decline, there was massive silting all over the city," he said. "It would appear there were major floods" that may have precipitated its fall between AD 500 and AD 600.

"Now, we have a much better idea of how these mega-floods impacted not only the people in the region but the societies, too," said Wilkerson. "I have no doubt that flooding is of greater significance than previously thought.

"What we have done on the salvage and excavation is going to be immensely helpful to the reinterpretation of the history of this region," said Wilkerson, who has kept detailed field notes of the unusual dig. "As a scientist, you don't stop because you are in grave trouble. You go on. There is scientific data that comes out of this. But, we are limited by our [financial] backing."

Study in Tropics Involves Dangers

The 55-year-old archeologist--technically a cultural ecologist specializing in how ancient man adapted to his environment in the tropics--has been in tough spots before. Beyond the routine camping, horseback riding, hiking and river fording the job requires, he was once detained by Guatemalan guerrillas on the Usmacinta River. A few years later, he survived the crash of a twin-engine airplane while leading a zoological team into the Lacondon Forest in southern Mexico. After the crash, they were detained for another week by the Guatemalan rebels.

The October 1999 cyclone provided new insight into patterns of sediments--used to understand ancient land movements, flooding and erosion. Previously, archeologists had assumed each layer of sediment represented a separate flood. However, digging through several sediment layers left by last year's deluge suggested a new interpretation.

"Some things we thought were the result of a series of floods perhaps were not a series but one catastrophic flood," Wilkerson said.

George Stuart, former chairman of the National Geographic Society's Research and Exploration Committee that helps fund Wilkerson's work, calls Wilkerson's latest dig "living archeology."

The society helps fund the Texas-based Institute for Cultural Ecology of the Tropics, which Wilkerson directs, and provided a small emergency grant this year. Wilkerson has run the shoestring recovery operation with the funds, plus a trickle of aid from sympathetic supporters and with workers and equipment sent by the Veracruz government.

Ancient People Lived With Flooding

At the center of Wilkerson's work is the question of how the ancient people of Veracruz turned rain forest into thriving urban centers and maintained a millennium-long balance with the delicate tropical environment. Part of the answer, he says, has to do with how they dealt with chronic flooding during a wet season that lasts for most of the year along Mexico's central Gulf Coast.

Since the 1970s, Wilkerson has examined the ancient farming technology used to transform the deltas, estuaries and surrounding hillsides of the Tecolutla and Nautla rivers into terraced agricultural plots. People still use a form of this ancient farming technology to grow orchids in the Xochimilco neighborhood of Mexico City.

The plots produced food for cities with tens of thousands of residents and helped contain flood waters, "providing water for dry season agriculture and removing excess water during the wet season," Wilkerson wrote in a 1983 British research journal.

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