Can someone help me with 6 or more quotations from Lord of the Flies relating to the aspect of male aggression?

Since the only characters in the book are males, any examples of aggression in Lord of the Flies are examples of "male aggression." Whether Golding specifically means to attribute these aggressive urges to males only cannot be established only by the text of the book. With that said, the boys do indeed exhibit aggression frequently in the novel. Many characters behave aggressively, not just those who might be considered antagonists. Here are some examples of different boys' aggressive behavior:
Ralph: Ralph shows aggression toward Piggy when Piggy has asked Ralph not to call him by the nickname he had at home: "He dived in the sand at Piggy's feet and lay there laughing. 'Piggy!'"
Roger: Roger first exhibits aggression by flinging stones from a hiding place at Henry, though he doesn't hit him: "Roger gathered a handful of stones and began to throw them." Later, Roger's strategic placement of the sharpened stick up the backside of the sow causes the sow's death: "The spear moved forward inch by inch and the terrified squealing became a high-pitched scream."
Hunters: All the boys who killed the sow take pleasure in their effort: "The sow collapsed under them and they were heavy and fulfilled upon her."
Jack: One of the most aggressive early acts occurs when Jack charges at Piggy and breaks his glasses: "Jack smacked Piggy's head. Piggy's glasses flew off and tinkled on the rocks."
The mob: At Jack's feast, the boys work themselves into a frenzy with their "dance," and when Simon appears, they descend upon him: "At once the crowd surged after it, poured down the rock, leapt on to the beast, screamed, struck, bit, tore. There were no words, and no movements but the tearing of teeth and claws." The boys murder Simon with their bare hands.
Samneric's captors: When the boys at Castle Rock capture Samneric, "they felt the otherness of Samneric, felt the power in their own hands. They felled the twins clumsily and excitedly."
Piggy's murderer: When Ralph and Piggy confront Jack's tribe at Castle Rock, "Roger, with a sense of delirious abandonment, leaned all his weight on the lever." This dislodges the boulder that kills Piggy.
These are some of the many examples of male aggression shown in Lord of the Flies.