How did humans discover that rice could be used as food?

South Korean archaeologists have announced that they have discovered the world's earliest edible rice. The discovery adds thousands of years to the history of this staple Asian food.

The report said archaeologists found 59 burnt rice grains in central South Korea, located between 36 and 37 degrees north latitude. The rice grains have been dated by radioactive methods to the earliest known era of crop cultivation, between 14,000 and 15,000 years ago.

Conventional wisdom holds that the charred rice grains found in China's Yellow and Yangtze River basins are the world's earliest rice, dating from 10,500 to 11,000 years ago.

The South Korean discovery supports earlier arguments by researchers that rice may have developed and evolved from areas farther north than the Yellow and Yangtze River basins in China.