While pigs are the only animals that feature in this poem, we do know that in The Odyssey, lions and wolves also roamed around Circe's house. Animals feature largely, for Circe's famous for her ability to transform men into animals with a flick of her magic wand. In this poem, she draws a distinct connection between animals and humans, arguing that there are times when humans behave like animals (and in those cases, she just helps them by making them look like the animals they mimic).