Ключевые слова: ancient, animal, big, creature, cretaceous, dinosaur, dinosauria, evolution, existed, extinct, extinction, giant, gigantic, herbivorous, jurassic, large, monster, nature, paleo, paleontology, prehistoric, prehistory, primeval, psittacosaurus, reptile, reptilian, saurian, sauropod, triassic, vertebrate, wondrous,