By the 1930s, dinosaurology had another problem besides the Depression. Dinosaurs had become so popular with the public that the subject had taken on something of a circus air, and paleontologists shied away from studying the creatures. They became reptilian curiosities, good for drawing crowds into the museum, but evolutionary dead ends of little theoretical impor¬tance. Besides, the number of dinosaur skeletons that can be found and studied is always limited. A comparable amount of work can produce dozens of fossil mammal remains, or tens of thousands of fossil invertebrates. In an era when mathematical studies of large populations are preeminent, this is an important reason why only a few dozen people study dinosaurs full-time.
The beginnings of today’s dinosaur renaissance can be traced to the mid-sixties, when John Ostrom’s digs in the midCretaceous of Montana found examples of a new species of Velociraptor. The remains revealed a strikingly birdlike, agile, and probably warm-blooded dinosaur. Ostrom also reexamined the Archaeopteryx specimens, and showed that they were theropods as well as early birds. The controversy surrounding these ideas did much good for dinosaurology; in fact, of the one hundred two species detailed in this book, forty-three were described after 1965 (although some of the latter remains were found before this date). Great gaps are being closed by these new finds. In particular, we finally have good mid/late Jurassic theropods, and know something about how the very first predatory dinosaurs looked.
Indeed, we are just beginning to understand what the dinosaurs really were. The view in vogue only two decades ago-that dinosaurs were slow, sluggish, dull-witted reptilian creatures is well out of favor now. Otherwise, almost everything is in dispute. Should dinosaurs be considered reptiles, or do they form a new group with birds? Were predatory dinosaurs warm or cold-blooded, or both? Were the giant tyrannosaurs walkers like elephants, or runners like ostriches? Theories abound, and if you want to get on the evening news, just come up with a new idea on what killed them off.