“Bug Off!” — The Discovery Files

If you thought that a beetle with a machine gun built into its rear end was something that only exists in sci-fi movies, you should talk to Wendy Moore at the University of Arizona. Many beetles secrete foul-smelling or bad-tasting chemicals from their abdomens to ward off predators, but bombardier beetles take it a step further. When threatened, they combine chemicals in an explosive chemical reaction chamber in their abdomen to simultaneously synthesize, heat and propel their defensive load as a boiling hot spray, complete with “gun smoke.”