presented by Thirteen for WNET.ORG ; Distributed by American Public Television ; A ParnassusWorks Film ; produced and directed by Richard Rifkind, Carole Rifkind
a Triumph Documentaries production ; produced and directed by Barbara-Langsam Shuman, Sharon Harris Pollack, Jill Mirowitz Mogil ; writer: Barbara Langsam Shuman
a presentation of the Howard Hughes Medical Institute ; produced by Sutherland Media Productions, Inc ; producer, Dennis WC. Liu, Ann DeStefano Sutherland ; director, Wally Ashby
produced by Bill Jersey & Michael Schwarz ; writers, Alex Beckstead, Jason Cohn, Bill Jersey, Max Salomon, Michael Schwarz ; Catticus Corporation ; Quest Productions ; Kikim Media ; KQED presentation