what are a few sources of the growing animosity between Jack and Ralph?

Ralph is concerned that the boys are not carrying out their practical duties. They are also giving in to fear which fuels Jack's leverage over Ralph. Jack offers the boys "fun" and little responsibility. Ralph is frustrated because he offers work and responsibility. Simon is perplexed. He is Golding's Christ-figure. This becomes more evident as the novel goes on. Simon attempts to smooth the animosity between Ralph and Jack although the negative energy seems to hurt him.

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