Archeologists have uncovered surprisingly sophisticated grain storage that predates plant domestication.

An excavation site near the Dead Sea in Jordan has revealed an 11,000-year-old granary, which even had elevated floors to prevent rodent pilfering and to increase air circulation.

The stone and mud building was capped with a wattle roof (branches or reeds woven around poles) was about 9.8 feet (3 meters) in diameter. The findings, reported earlier this week in Proceedings of the National Academy of Sciences, reveal wild barley as one of the ancient building's contents. Two nearby structures also appear to have been used for food and grain processing.

People in the Early Natufian period (15,000 to 12,800 years ago) were fairly sedentary but appear to have depended largely on the day-to-day availability of wild plants and animals for food, rather than food stores. But by 11,000 years ago, people seem to have made great strides, building silos and these more complex granaries.

The structures "represent a critical evolutionary shift in the relationship between people and plant foods," the study authors write. This step "precedes the emergence of domestication and large-scale sedentary communities by at least 1,000 years."

This sort of development may have begun early human settlements on their way to a better understanding of the potential of plants—and what would eventually become agriculture.

Interpretive rendition of the granary, courtesy of the National Academy of Sciences, PNAS