When Ralph wounds the boar, he feels the excitement of hunting for the first time. Up until this time, he has left the savagery of the hunt to Jack and his gang of hunters. When Ralph throws his spear in a split second decision, he is elated by the feeling of the hunt and the victory of having hit the boar. Unfortunately, Ralph only wounded the boar and it got away. Because of this fact, he is still not accepted by the group of hunters.
The fact that Ralph wounded the boar develops the theme of an internal beast. The hunting lust shown by Ralph shows that he has a dark side within him. Furthermore, Ralph's victory has not recieved much attention from the boys unlike Jack's triumph of coming close to killing a boar. At this time, Jack was still somewhat civilized thus the reason why he couldn't completely kill the pig. Similarly, Ralph's incapability to kill the boar symbolizes his civilized soul, but savage instinct.