The crustacean subphylum can be broken down into decapods, amphipods, copepods, and other types. This title offers readers from grades one through four comparisons between the needs and roles of different crustaceans, which will allow readers to understand the subphylum's importance. Readers will recognize and expand their knowledge about familiar species like the lobster and the shrimp, while being introduced to the likes of the wood louse and zooplankton...