Best-selling author Chelsea Clinton will present her new children’s book, Don’t Let Them Disappear: Twelve Endangered Species Across the Globe, at a special event and book signing May 23, 2019 at the San Diego Zoo.

Chimpanzees are well known for their extraordinary diversity of behaviors—including using tools for hunting or digging, cracking nuts with stones and using moss as a water-drawing sponge—with some behaviors also exhibiting cultural variation.

San Diegans Ernest and Evelyn Rady have made a record-setting commitment in support of the San Diego Zoo’s Animal Ambassador program. The Radys have pledged $20 million, of which $15 million will be a challenge grant that must be earned with matching donations from other Zoo supporters.