When researchers stumbled upon a buttery substance under a lake, they thought maybe they'd also stumbled upon the answer to an age old mystery: why a pre-Columbian civilization near St. Louis abandoned the complex city they'd built. But with multiple research teams exploring the Cahokia Mounds site, not everyone agrees on what the new discovery means.
Guests:
- Sissel Schroeder, University of Wisconsin
- Melissa Balthus Zych, University of Toledo