Researchers from the University collected sediment core samples, revealing layers of ash from burned reed and cane plants, as well as remains of burned osteons that indicates that the mounds were likely used for ceremonial purposes.
A radiocarbon analysis of the material suggests that the mounds were built over thousands of years, with construction of Mound B starting around 11,000 years ago.
Read more: MOUNDS IDENTIFIED AS OLDEST MAN-MADE STRUCTURES IN NORTH AMERICA
