The use of animals in literature can be seen all throughout history. Anthropomorphism is a pervasive element of literature, employed by many different authors, of many different genres, to imply many different things, usually some sort of social criticism. According the American Heritage Dictionary, anthropomorphism is "the attribution of human motivation, characteristics, or behavior to inanimate objects, animals, or natural phenomena." From Aesop's Fables to Winnie-the-Pooh to Animal Farm, and everything in between, authors have used the animal kingdom as a way of saying that which human characters cannot. Everything about these characters, from the actual animal chosen, to the manner in which they speak, to the lessons that they learn and teach, reveals a great deal about the author's purpose for writing the story. It is very rare that a children's or adolescent's book is simply a sweet tale; in fact, quite often, there is some pervasive commentary that author is striving to convey. These lessons range from an ideal set of morals in Aesop's Fables, to a comment on certain undesirable human characteristics in Winnie-the-Pooh, to a criticism of the current political standing in Animal Farm. They say that people are a product of their environment. If these books, and others like them are part of an adolescent's environment, then perhaps they will become a more educated in the ways of the world.
One of the first recorded instances of anthropomorphism in literature is Aesop's Fables. There is not much known about Aesop, other than that which others have recorded. He has become somewhat of a mythical figure, in which certain things are simply attributed to him, much like many nursery rhymes are attributed to Mother Goose. What is known is that most likely, he was born a slave in the 6th century B.C. It is believed that he gained his freedom from slavery as a reward for his learning and wit.