This book is based on the author's phD thesis, which won the 1996 ACM Doctoral Dissertation Award. The author proposes and develops an artificial life paradigm for computer graphics animation by systematically constructing artificial animals controlled by self-animating autonomous agents. The animation agents emulate the realistic appearance, movement, and behavior of individual animals, as well as the patterns of social behavior evident in groups of animals. The paradigm is based on a computational model capturing the essential characteristics common to all biological creatures: biomechanics, locomotion, perception, and behavior. The approach is validated through the implementation of a virtual marine world inhabited by a variety of lifelike artificial fish, where each fish is a functional autonomous agent.