The book is about stories of various animals on the earth Tens of millions of years ago in the Archaean.Among these animals which had lived in the Archaean, some have been extinct; some have evolved.Their bones remain in the strata and become fossils.Relying on the excavation and sorting of the fossils, we can understand what kind of animal climbed and flied on the ancient crustal.The book talks about dinosaurs, trilobites, primitive fish, Archaeopteryx, primitive horses as small as foxes and other animals. Readers can obtain general knowledge about prehistoric lives here.