After the death of Curly in The Call of the Wild, Buck concludes that no fair play exists in his world and that he will never go down in a fight. The theme illustrated here is apparently derived from London''s interpretation of

Respuesta :

The answer to the question is the theory of Evolution. Throughout The Call of the Wild, Buck gradually transforms from a peaceful dog into a wild animal. Buck realizes that to survive in the world, he must adopt a survival of the fittest attitude, which derives from the theory of Evolution.