Katharine Payne, research associate and visiting fellow at Cornell University, describes her 12-year study of the acoustic life of elephants. Working extensively in Kenya and Namibia, she recorded the wide range of communications -- some out of the range of human hearing -- that bind together individual elephants in a complex network of relatives and acquaintances. Payne's recently published book, Silent Thunder: In the Presence of Elephants, will be available for purchase and signing. Please call 212-769-5200 for reservations. Program code: ED98224L Fee: $15.