Everybody poops

"Everybody Poops: Using Fecal Stanols to Track Cahokia Region Population Change and Evaluate Ideas on Cahokia’s Decline" presented by A.J. White, Graduate Student, Anthropology, UC Berkeley.
Abstract: Fecal stanols provide a proxy of population change by identifying variations in the amount of trace human waste products retained in sediment. We used fecal stanol data from Horseshoe Lake, Illinois, as a population proxy to evaluate the role of flooding, droughts, and environmental degradation in Cahokia’s demographic decline. We find that both Mississippi River flooding and warm season droughts detrimental to maize agriculture occurred at ca. 1150 CE, shortly after Cahokia’s population maximum as identified by fecal stanol concentrations. Fecal stanols then decrease steadily to a minimum at ca. 1400 CE, suggesting environmental stressors of the mid-12th century played a significant role in Cahokia's decline. Because everybody poops, we can use human waste to assess the impact of environmental events on a population.