Here’s a defense mechanism that’s new and different: shoot boiling vapors out your rear end. That’s what the Bombardier Beetle does. When attacked, it fights back by firing a chemical spray of a caustic, foul-smelling gas. The beetle can fire up to a dozen times, and each spurt produces an audible pop. The spray itself can blast an enemy as far as two inches away.
The spray is produced by the mixing of two different chemicals which the beetle stores in separate glandular compartments. One compartment contains a solution of hydroquinone and hydrogen peroxide, and the other contains a mixture of enzymes. When harrassed, the beetle mixes the contents of these two compartments. A chemical reaction takes place which produces so much heat that the vapor actually reaches the boiling point.
Then all the beetle has to do is point its rear end at the enemy and fire away.