Cephalopods are the most intelligent invertebrates. Scientists have discovered that octopuses, for example, have a good memory and can be taught to perform tricks! Few books explain the scientific classification of animals as well as What is the Animal Kingdom? All creatures, including insects, mammals and fish, are classified and described from simple animals like sponges to the larger brained mammals such as humans. Young readers will learn all the basics of kingdoms and species that form an important foundation for the study of biology. A special section reveals tat animals are being threatened by illegal hunting, human development and pollution and suggests actions that readers can take to help stop their destruction.