Tuesday 10 April 2007

Maize farming found to predate Mayans by a millenium

New evidence has surfaced to suggest that ancient farmers in Mexico were cultivating an early form of maize, the forerunner of modern corn, about 7,300 years ago - 1,200 years earlier than scholars previously thought.

The findings expand on previous research that demonstrate the rapid spread of maize from southwest Mexico to the southeast and other tropical areas in the Americas, including Panama and South America.

Through an analysis of sediments in the Gulf Coast of Tabasco, Mexico, Florida State University anthropologist Mary Pohl concluded that people were planting crops in the ‘New World’ of the Americas around 5,300 B.C.

"This research expands our knowledge on the transition to agriculture in Mesoamerica," Pohl said. "These are significant new findings that fill out knowledge of the patterns of early farming.”

The shift from foraging to the cultivation of food was a significant change in lifestyle for these ancient people and laid the foundation for the later development of complex society and the rise of the Olmec civilization, Pohl said. The Olmecs predated the better known Mayans by about 1,000 years.

During her field work in Tabasco seven years ago, Pohl found traces of pollen from primitive maize and evidence of forest clearing dating to about 5,100 B.C.

Pohl's study analysed phytoliths - the silica structure of a plant - from traces of maize pollen that previous studies have found to date back to about 5,100 B.C. Her analysis puts the date of the introduction of maize in southeastern Mexico 200 years earlier than her pollen data indicated.

It also shows that maize was present at least a couple hundred years before the major onset of forest clearing. Traces of charcoal found in the soil in 2000 indicated the ancient farmers used fire to clear the fields on beach ridges to grow the crops.

"This significant environmental impact of maize cultivation was surprisingly early," she said. "Scientists are still considering the impact of tropical agriculture and forest clearing, now in connection with global warming."

The discovery of cultivated maize in Tabasco, a tropical lowland area of Mexico, challenges previously held ideas that Mesoamerican farming originated in the semi-arid highlands of Mexico and shows an early exchange of food plants.

A report on the results of the study will be published in the April 9-13 edition of the U.S. journal, Proceedings of the National Academy of Sciences. More information is available from the Florida State University’s press release.

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