Describe Buck's character development.

Buck is stolen by the gardener and sold to a group traveling north. Before long Buck knows that he is in a strange land with different rules and expectations. A man in a red sweater teaches Buck his first lesson of the Northland: "a man with a club was a law-giver, a master to be obeyed, though not necessarily conciliated." Buck's first masters are just, but he must make a difficult adjustment to his new life of labor and near-starvation. He even steals food from his master, an act which marks "the decay or going to pieces of his moral nature, a vain thing and a handicap in the ruthless struggle for existence." Although Buck is a dog, his "development (or retrogression)," as London calls it, is depicted in almost human terms. He is losing all the trappings of civilization. "The domesticated generations fell from him," and "instincts long dead became alive again."

Buck is more and more drawn to the wild. He discovers the thrill of the blood hunt, and he defeats his rival, Spitz, for the position of lead dog. But when he meets his third master, John Thornton, a strong relationship develops between man and dog. Buck stays with Thornton because he loves him, not because of the "law of the club." He risks his life for Thornton on more than one occasion. Yet he is still attracted by the call of the wild. He meets a wolf, a "brother," and longs to run off with him, but he stays with Thornton. Only when Yeehat Indians murder Thornton does Buck join the wolf pack, becoming the "Ghost Dog" in Yeehat legend. The wolves are greatly feared, and Buck "may be seen running at the head of the pack."