Enter the Prehistoric World to Explore the Size of Dinosaurs! In soft watercolors, this story introduces the concept of comparing sizes rather than taking measurements. Just like many little ones, Pipkin the penguin has a number of difficult questions about the world around him, but his biggest question of all is about the size of prehistoric dinosaurs. He knows that dinosaurs were very big, but just how big were they? Following his mother's suggestion to look to the past to find the answer, Pipkin travels back in time. Join him on his journey as he discovers that one dinosaur might be bigger than a second dinosaur, but not quite as big as a third!