In Lord of the Flies, there is a battle between Ralph and Jack for leadership and control over the boys and Ralph, "with the trumpet-thing"(ch 1) is chosen as leader as the boys are impressed, even mesmerized by the conch. It becomes the symbol of authority and order, the closest thing to a democracy such as the boys are used to. Rules and regulations are in the fiber of the boys because "After all, we're not savages. We're English..."(ch 2) Ironically, it is Jack who says that but he never willingly accepts the authority of the conch, except when he can use it for his own purposes. He finds his own symbol of authority and its sharp contrast to the attractive conch, reveals the very different kind of authority that Jack recognizes and his "tribe," the hunters offer the pig's head to the "Beast" as "a gift." So, whilst both symbolize power, the conch draws the boys together and restores confidence, whilst the pig's head terrifies them.
The suggestion therefore is that there is a struggle within everyone between right and wrong, good and evil. The boys can choose to recognize the conch and rules will be followed and order maintained or they can choose to uphold the pig's skull, as it deteriorates, just like the kind of power that Jack exerts, a power that causes the boys to descend into a place they do not recognize, even Ralph being ultimately effected. As Ralph cries for "the end of innocence," (ch 12) he is basically admitting that the return to savagery was able to overrule good order. Interestingly, the boys are rescued and, presumably, order restored so the power of the beast and its symbol, the pig's head/skull, is not sustainable and, although the conch has been smashed, what it represents can still prevail.