1,000 Years Ago, Corn Made This Society Big. Then, A Changing Climate Destroyed It

About a 15-minute drive east of St. Louis is a complex of earthen mounds that once supported a prehistoric city of thousands. For a couple of hundred years, the city, called Cahokia, and several smaller city-states like it flourished in the Mississippi River Valley. But by the time European colonizers set foot on American soil in the 15th century, these cities were already empty.

Scientists cannot seem to agree on what exactly led to the rise or the fall of this Mississippian American Indian culture, a group of farming societies that ranged from north of the Cahokia site to present-day Louisiana and Georgia. Possible explanations have included massive floods and infighting. But a recent study heaps new evidence on another theory, one contending that changing climate, and its influence on agriculture, were the forces that made the cities flourish, then drove them to collapse.

http://www.npr.org/sections/thesalt/2017/02/10/513963490/1-000-years-ago-corn-made-this-society-big-then-a-changing-climate-destroyed-the