The poem "The Hyenas" uses the scavenger as a metaphor to humans in both our actions and our morals. The link does a good job of summing it up. Basically it's about hyenas who dig up a dead soldier. It focuses on their lack of shame for defiling a dead soldier of the king because they are considered wild animals. It's in their nature to act in such a manner. Kipling ties that into the morality of human beings as well.