Jack London in, "To Build a Fire," does contrast the dog to the man. As a naturalist, London sees humans as biological creatures, the same as any other creatures. In fact, humans, when pitted against natural forces, are inferior creatures.
The dog is built to withstand the cold and ice, etc. It does not need a fire to survive. The man does. The only danger the dog faces is from the man when he tries to catch and kill the dog in order to warm himself inside of the dog's warm carcass. But even here, the dog's superior instincts make it suspect something and move out of reach.
The dog is loyal to the man, and waits as long as it can once the man freezes to death. But it doesn't need the man. It eventually trots away on to the next camp, where food and shelter and warmth await.
I have always found many human characteristics in the way Jack London presented the dogs in his novel, Call of the Wild. In many ways they are better than most of the men found in the book. The dogs take pride in their work, and most of them unite as a team. Although they fear their human masters, they also show respect for the ones with quality traits. Dave works himself to death; Sol-leks is proud and dedicated. Buck displays many characteristics desirous of outstanding men: prideful, strong, independent, loving, cunning. Most of the men found in the novel are weak and cruel, and they treat the dogs as one would a piece of property. When the dogs are worn out or too weak, they become disposable. The men's goals are mostly money-oriented, but they also realize the dogs are a key ingredient to achieving successful mail runs and transport. Since the dogs are the main characters of the story, London has wisely given them personalities which create both interest and sympathy from the reader.