How does the author use the incident of the wild dog attack to propel the action and the suspense in the text?

Suddenly everyone realizes that four of five starving huskies have invaded the camp. They pounce on the food, crazed by its smell. The team has never seen such dogs. Gaunt skeletons with eyes and fangs. The strange huskies attack, and Buck finds himself viciously fighting for his life. The wild dogs are emaciated and starving. Hunger becomes a reoccurring motif through the story. At this point Francois and Perrault feed Buck but this event foreshadows hunger and survival to come later in the story.