This title introduces readers to fossils from dozens of ancient species. The book explores the remains of plants that grew during the Paleozoic Era, animals that walked and swam during the Mesozoic Era, and early humans that evolved during the Cenozoic Era. Features include a glossary, additional resources, and an index. Aligned to Common Core Standards and correlated to state standards. Encyclopedias is an imprint of Abdo Reference, a division of ABDO.