Botanists Establish Origin of Corn

Discovery of fossilized grains of 60,000 year old corn pollen 200 feet beneath Mexico City last year has definitely established that corn is a native of the Western Hemisphere and did not originate in Asia, four University botanists announced Saturday.

The origin of corn, America's most important food plant, has puzzled botanists for more than a century.

At the same time, the scientists also said that corn is not a descendant of a Mexican grass called teosinte. This grain, however, has had an important place in the development of modern corn through natural hybridization processes, the botanists added.

Final Evidence

By mating modern corn and teosinte, a synthetic hybrid corn cob was developed which closely matched, in size and botanical characteristics, prehistoric corn cobs found in caves in the southwestern United States.

The University botanists concerned with the research include Paul C. Mangelsdorf, professor of Botany; Elso S. Barghoorn, associate professor of Botany; Walton C. Galiuat, a research follow; and Miss Margaret Wolfe of Radcliffe.

The discovery of the 60,000 year-old pollen last year was the final evidence the scientists needed to prove that corn originated in this hemisphere.

In 1950, the oldest and most primitive corn cobs--scarcely larger than a one-cent piece--were found in Bat Cave, N.M. They are estimated to date from 3000 to 3900 B.C., the botanists revealed. The plant bearing these cobs was thought to be a slender shoot, one or two feet in height.

Comparison Made

By comparing the Bat Cave cobs with later corn known to have been crossed with teosinte, the scientists obtained evidence of the value of teosinte. In addition, they experimentally proved that cross-breeding with teosinte causes corn to mutate and increase in variability, thus becoming more susceptible to human selection.

The Mexico City corn pollen fossils were found in drill cores studied by Dr. Paul Sears of Yale and Mrs. Kathryn Clisby of Oberlin College. The Bat Cave corn was found by Herbert Dick, then of Colorado State Museum.