What is intelligence? From where did it come? Will the human brain grow and adapt to the ever-changing world? These and many other questions are addressed in The Origin and Evolution of Intelligence. This volume is composed of a series of articles presented on the origin and evolution of intelligence in March 1995 at the Eighth Annual Symposium of the UCLA Center for the Study of the Origin and Evolution of Life (CSEOL). The six authors of the contributions to this volume discuss in detail an enormous span of invertebrate and vertebrate life forms and wrestle with a vast array of problems ranging from direction finding in ants and birds to sociopolitical communication in monkeys, symbol manipulation in apes, and language use in humans. All these phenomena may be grouped under the general term intelligence, the unifying theme of the volume.