The main conflict is Buck fighting against his masters and his development from a tame dog into a wild wolf. This drives the plot because it shows the life of Buck as he is exposed to the harshness of the world from his first taste of abuse to his first life and death dog fight and his being punished for the wildness that is in him to the end where he buckles under the influence of the wild. This shapes Buck's characterization because in the beginning of this story, he is a tame, gentle giant who lived in the south. A pretty soft dog who didn't have anything to worry about. However, this changes from the first time a man hits him and his first dog fight. The conflict is resolved In the end by Buck's dearly loved master being killed. After this, Buck throws the law of the club away, and kills many Indians, those who killed his loved master. After he does this, he goes to run with his wild brothers and caves to his instincts and becomes a wild wolf.
Well...it might be that old "supply and demand" factor. As one example: a corporation/rancher/farmer might have the "demand" and the immigrant might have the "supply."
