This thick-headed lizard had a skull that was 10 inches thick and covered in bumps and spikes. The pachycephalosaurus lived in the late Cretaceous period and was one of the last dinosaurs to have lived. This fascinating volume follows a young pachycephalosaurus through the trials of daily life. Every thrilling moment is described in easy-to-follow text, from being chased by a T-rex to battling for food. A detailed description of the dinosaur informs young paleontologists of the strengths and weaknesses of the pachycephalosaurus. Fossil facts explain how fossils were discovered and how scientists use fossils to guess how the dinosaur lived.