This little beetle has one of the most fascinating and confusing chemical defenses in nature. Inside its body, it houses three chemicals that, when blended, create a boiling hot liquid that burns and stings an attacker.

How powerful is it? “If the beetle’s explosion chamber were the size of the inside of a car,” Eric Arndt, a doctoral student at MIT tells KQED Science, “the blast would release about the same energy as about two pounds of TNT.”

The enzyme that sets the whole reaction off is kept in a separate chamber inside the beetle. But that has left scientists scratching their heads — how did the beetle evolve to do this without the early ancestors blowing themselves up? This video explains the theory on how the bombardier beetle came to be.

"Enzymes, which are derived from our DNA, have long been known to evolve, becoming increasingly specialized over time. In theory, scientists assert, an early relative of today’s bombardier beetle might have possessed a less potent version of the enzyme, all part of the gradual emergence of the system."

A team of researchers at several universities are looking into the ancient history of the beetle's family line, and hope to determine at a molecular level how these amazing beetles crafted such a specialized self-defense weapon over the ages.

Jaymi Heimbuch ( @jaymiheimbuch ) focuses on wildlife conservation and animal news from her home base in San Francisco.

How did the bombardier beetle become so explosive?
Able to shoot a boiling hot chemical at aggressors, this beetle has long been a mystery of evolution.