Theropod Giants and Feathered Dinosaurs
The story of predatory dinosaurs began during the early stages of dinosaur evolution with the appearance of the first theropods in the Late Triassic Epoch. By the Middle and Late Jurassic Epochs, the evolutionary lineages of meat-eating dinosaurs had diversified dramatically, leading in one direction to such large carnivores as Allosaurus (Late Jurassic, western North America) and in another direction to such small, chicken-sized insectivores as Compsogna-thus (Late Jurassic, Germany). The Late Jurassic was also witness to the evolution of the first known bird, Archaeopteryx (Late Jurassic, Germany), from theropod ancestors, whose mosaic of traits included wings and feathers as well as a very unbirdlike tail and toothy mouth.
The evolution of theropods was in full bloom during the latter Jurassic, seemingly keeping pace with an ever-broadening array of prey animals, including dinosaurs, insects, lizards, and small mammals. Significant as it was, however, theropod evolution of the Jurassic Period pales in comparison to the truly explosive development of carnivorous dinosaurs of many kinds during the Cretaceous Period that followed. The theropods of the Jurassic laid the groundwork for an even greater spurt of predatory dinosaur evolution that led to the development of feathered dinosaurs, hulking meat eaters, swift and agile pursuit predators, ostrichlike dinosaurs, and the largest carnivorous animals ever to walk on land, including Tyrannosaurus (Late Cretaceous, western North America); Giganotosaurus (Late Cretaceous, Argentina); Mapusaurus (Late Cretaceous, Argentina);
Carcharodontosaurus (Late Cretaceous, North Africa); and Spino-saurus (Late Cretaceous, North Africa). This chapter explores the last great families of carnivorous dinosaurs that flourished during the Early and Late Cretaceous Epochs.
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