More than 154 million treasures fill the Smithsonian’s vaults, but where public view ends, Sidedoor begins. With the help of biologists, artists, historians, archaeologists, zookeepers, and astrophysicists, host Lizzie Peabody sneaks listeners through Smithsonian’s side door to search for stories that can’t be found anywhere else. Follow Sidedoor at @SidedoorPod or sign up for the e-newsletter at www.si.edu/Sidedoor