Awesome Ancient Animals follows the evolution of animals. Huge Hunters Roam the Earth takes you back to the Tertiary Period. During this time, great open plains of grass formed. Mammals from this time developed long legs to suit this new environment.
"Describes the animals of the Tertiary Period, when huge open plains of grass formed, and mammals developed long legs to suit this new environment. Includes an Animal Families glossary, prehistory timeline, and pronunciation guides"--