Bombardier beetles are examples of:
Bombardier beetles combine an effective chemical defense with conspicuous cues that predators can learn to avoid. When threatened, they mix stored hydroquinones and hydrogen peroxide with enzymes in a reinforced reaction chamber, generating hot, irritating quinones that are expelled in rapid pulses. The reaction can approach the boiling point of water, and the beetle can direct the spray toward an attacker. Many species also display contrasting coloration or characteristic postures that can function aposematically by advertising their defensive capacity before discharge. A predator that associ
Ref: Evolutionary Analysis, Herron & Freeman, 5th Ed., Ch. 10
