A beetle mixes two chemicals inside its own body to fire a boiling, corrosive spray

When threatened, a bombardier beetle combines hydroquinones and hydrogen peroxide in an internal reaction chamber, triggering a reaction that heats the mixture near boiling and blasts it out in rapid pulses, aimed by a rotating nozzle at the tip of its abdomen. Chemist Thomas Eisner spent decades documenting exactly how the beetle survives a small explosion happening inside its own body.

— Thomas Eisner, For Love of Insects — 2003
Go deeper: get the book →