A large-scale genomic study of the Poverty Point earthworks in Louisiana has identified a distinct genetic differentiation between individuals buried in central monumental mounds and those in outlying residential areas. Published in Science Advances, the research indicates that this hunter-gatherer society maintained a rigid, hereditary social structure 3,500 years ago, far earlier than previously assumed for non-agricultural groups.
The data also reveals a 'ghost' ancestry component that links the Poverty Point builders to earlier Archaic period populations from the Great Lakes, suggesting a massive, long-distance migration event that brought sophisticated earth-moving knowledge to the Lower Mississippi Valley.