Micro

by Michael Crichton

Bombardier beetles got their name from their ability to fire a hot, noxious spray in any direction from a rotating turret at the tip of their abdomen. The spray was sufficiently unpleasant that it stopped toads and birds from eating them, and it was toxic enough to kill smaller insects immediately. How bombardier beetles accomplished this had been studied since the early 1900s, and by now the mechanism was well understood. “The beetles produce boiling-hot benzoquinone spray,” she explained, “which they make from precursors stored in the body. They have two sacs in the rear of the abdomen—I’m cutting them open now, there, you see them? The first sac contains the precursor hydroquinone along with the oxidant, hydrogen peroxide. The second sac is a rigid chamber, and contains enzymes, catalases, and peroxidases. When the beetle is attacked, it muscularly squeezes the contents of the first sac into the second, where all the ingredients combine to produce an explosive blast of benzoquinone spray.”