Amazon.com description: Product Description: For 140 million years the dinosaurs were the dominant life-form on Earth. Between the Triassic and Cretaceous periods hundreds of species of dinosaurs evolved, from the ferocious carnivore, "Tyrannosaurus" to the placid herbivore "Diplodocus." Possessing a unique reptilian bone-structure, the dinosaurs were a remarkably diverse species whose descendants remain with us in the form of birds. "The Historical Atlas of the Dinosaurs" plots the development of these monstrous rulers of the planet from their emergence from the ocean, through their dispersal across the shifting continents and their gradual evolution, to their sudden and mysterious extinction 64 million years ago.