Three cheers for the Terrible Lizards--from a world-class authority who likes nothing better than to shake the academic tree--not to mention the evolutionary tree--by generating new and ingenious theories about your favorite fossils. Bakker is best known for touting the idea that dinosaurs were warmblooded. In this magnum opus Bakker not only offers six' kinds of evidence for warmbloodedness, but also elaborates on how dinosaurs ate, ambulated and copulated; how they fought, lived, and died. He's the first to admit that a lot of what he has said has been called heresy. But he has turned more than one expert around and by the end of the book, readers may well be convinced that he's more right than wrong. Interestingly, Bakker does not back the modish theory that dinosaurs died suddenly 65 million years ago as a result of extraterrestrial collision and sky darkening. (They were well on the wane by that time, he avers, probably because of an accumulation of geological changes: inland seas dried up and widely separated species could then mix, with the potential for ecological disaster--runaway population explosions; introduction of new germs, etc.) Bakker bases his warmblooded ideas on a deep knowledge of biomechanics, metabolism, comparative anatomy and physiology. For example, bone analysis indicates rapid growth for dinosaurs--consonant with the high rates of metabolism of other warmbloods. Anatomy and fossil footprints indicate high rates of locomotion--enabling tyrannosaurs to chase prey and maintain the high calorie intake mammals require. Bakker is brilliant in piling on argument on argument to build his case and is positively skin-crawly as he describes, say, the super spikes and scimitar teeth that various dinosaurs used in defense and attack. And just in case you miss the verbal point, his drawings of fancied combat or family trees, his contemporary detailing of how a boa constrictor swallows, or a chameleon walks, are explanatory treats to behold. Incidentally, he concludes that dinosaurs belong to a class of their own. So does Bakker's book: and it's a high one.