A Pig's Head and Societal Evolution

These are answers I made in a sociology quiz last week on the movie "Lord of the Flies", which I'm fairly proud of, so I'm posting them. Besides, it's my way of thinking, too, sometimes. Especially the second one.

What does the pig's head on the stick
represent/signify?
Superstition; humanity's propensity towards believing in mythological beings they image (teacher note: Sacrifice or offering to "beast")

Explain how this story is similar to the
evolution of our society.
It's evolution, backwards. They (the boys marooned on an island) went from civilized to representing older and less "civilized" cultures. They start out as a tentative democracy, then they split under internal rivalries and they end up starting to kill others. Though it also represents society evolution forwarding itself - a weak leader is defied by the strong, the strong bring about change, purge those that do not convert to their way, and then that new structure inevitably falls sooner of later, depending on circumstances. Ralph's democratic rule was short lived because weakness and a lack of success negotiations failed to keep Jack content with being second best.