Buck has a recurring dream of his distant ancestors. Namely, those animals who came before him and lived side by side with primitive man. These dreams become more prominent and vivid as the story progresses indicating Buck's transformation back into a more wild creature. Initially, Buck doesn't necessarily know what to make of the dream. It causes him restlessness. Eventually, he "acts" upon the dream, heeding the "Call of the Wild," and going back to roam with the wolves who live in the wild. On the surface, these dreams appear as just that, i.e., dreams. Some thought on them indicates that they are more than just random thoughts. They are, in reality, his true nature, the sounds of his heart, coming to fruition, speaking to him in the form of dreams. These dreams become a driving impetus for the realization of his destiny.