Buck is a dog and was stolen by thieves and taken to be come a sled dog then he was had to pull the sled even when he was extremely tired like a living hurricane of fury, hurling himself upon them in a frenzy to destroy. He sprang at the foremost man it was the chief of the Yeehats ripping the throat of a second man.” (London 100). Buck got treated bad and he was pushed over exhaustion this is what made him crack.
Buck getting treated bad made him turn on other dogs and humans. “Like a flash Buck struck, breaking the neck. Then he stood without movement as before the stricken wolf rolling in agony…” (London