A long history of literature, particularly literature for children, features animal characters. Aesop, a Greek slave and writer who lived between the 7th and 6th century BCE, wrote fables that conveyed lessons. Most of his fables use animal protagonists and antagonists, whose situations refer to important truisms, such as “it is important to be honest” or “act with humility.”

Animals as protagonists create emotional distance that can make stories’ messages more palatable. For example, in one of Aesop’s fables, about a lion, an ass, and a fox, the lion asks the ass to divide food up between the three animals. When the ass gives each of the three animals equal amounts, the lion is angry and kills him. When the fox is asked to divide up the food, he gives the lion the greater portion. The lesson, or moral, of this tale is to learn from the misfortune of others. Had this story contained human characters, however, the action might have felt more shocking, whereas having a lion kill an ass seems within the spectrum of behavior one would expect from a powerful carnivore and is less disturbing. Similarly, in the more modern fable The Ugly Duckling (1843), by Danish poet and author Hans Christian Anderson, the story—about an ugly young bird who was mistaken for a duckling but turns into a beautiful swan—seems more lighthearted and less disturbing than a tale about an exceptionally ugly and therefore maligned child would be (Burke, Carolyn & Copenhaver, Joby.