Why is White Fang so important? What happens to White Fang at the end of the story?

White Fang is the novel's protagonist. He is the epitome of the "survival of the fittest", as he is the only one of his litter to survive a famine. He gains a reputation as one of the most ferocious dogs in the Northland, but eventually is civilized. In the end, White Fang makes his home at Judge Scott's, where he mates with Collie and sires a littler of puppies.