The leopard, lion, and she-wolf that menace Dante in his quest to get to the sunlight all represent different types of sin. Traditional interpretations have parsed the leopard as a symbol of fraudulence, the lion as a symbol of pride, and the she-wolf as a symbol of avarice or greed. The leopard has few physical characteristics suggesting its interpretation as fraudulence, but the prideful lion has his "head held high."
The she-wolf is described most fully. She "carr[ies] every craving in her leanness," meaning she is painfully skinny. Which explains why she represents avarice or greed. She’s got nothing! But even more interesting is Virgil’s explanation that a Greyhound will eventually come to kill the she-wolf and "restore low-lying Italy." This seems to imply that greed afflicts the whole country. Well, we know that this is true for Florence, given the city’s illustrious textile and banking industry and the political squabbling taking place there at the time. However, nobody can agree about whom the Greyhound represents.