What traits do all animals share? And is their behavior innate or learned?
There is great variation among species that make up the animal kingdom. Some of this variation is shown in the figure above. Despite the variation, there are a number of traits that are shared by all animals. The fact that all animals have certain traits in common shows that they share a common ancestor. Characteristics, classification, and behavior of animals will be addressed in the Animals chapter.
Animals. Currently the end of the line for evolution. But there are all sorts of animals, from the extremely simple to the outrageously complex. Animals introduces the basic characteristics of animals, and discusses their classification and their behaviors.