Write an essay that analyzes a theme in The Call of the Wild.

He Call of the Wild is a story of transformation in which the old Buck the civilized, must adjust to the harsher realities of life in the frosty North, where survival is the only imperative. As Buck realizes from the moment he takes a step off the boat and watches the violent death of his friend Curly, the wilderness is a cruel, uncaring world, where only the strong survive and the weak die. It is, one might say, a perfect Darwinian world, and London’s depiction of it owes much to Charles Darwin, who proposed the theory of evolution to explain the development of life on Earth. In the wild kill or be killed

im not sure about this one