DINOSAUR! by David Norman (Prentice Hall: $15; 192 pp., illustrated). Based on the four-part television series, this well-balanced account traces the history of paleontology and the changing image of dinosaurs, from clumsy, stupid lizards, to active, well-adapted, endothermic animals. Unlike many popular science writers, Norman avoids giving sensational or simplistic answers to complicated questions, including the mystery of extinction. He presents the most widely accepted theories and the evidence that supports them, allowing the reader to accept or reject the ideas. With “Jurassic Park” devouring box office records and more dinosaur films due this fall, “Dinosaur!” offers adults (and junior paleontologists) an intelligent introduction to a fascinating group of animals.