"The bombardier beetle shoots its enemies with a boiling hot chemical weapon that evolved millions of years before its modern analog in human technology: automatic valves in the pulse-jet engine of the German V-1 flying bomb the terrifying 'buzz bomb' of World War II that rained indiscriminate death on England."Three Cornell University biologists, working with the late Professor Harold (Doc) Edgerton of MIT, have discovered this surprising anticipation of technology by nature. Writing in a recent issue of Science, Cornell scientists Jeffrey Dean, Associate Professor Daniel J. Aneshansley, and Professor Thomas Eisner explain their remarkable discovery, which required co-author Doc Edgerton's high-speed photography to catch the beetle in action.
Dr. Eisner explained the cycle that apparently occurs within the beetle an average of about 500 times per second: "The bombardier beetle uses what is essentially a binary weapon. It stores the two ingredients of an explosive chemical process hydroquinones and hydrogen peroxide in a pair of reservoirs, and the catalysts for the reaction...in [another] pair of reaction chambers."When the beetle is disturbed, muscles around the reservoirs contract just enough to force a little of the hydroquinones and hydrogen peroxide through one-way valves that are normally closed. As the catalysts start the reaction, heat and pressure of the oxygen [liberated from the hydrogen peroxide] quickly close the valves. Pressure continues to build until the reaction chambers vent through the tip of the abdomen with a high velocity pulse of quinones." Then the reaction chamber pressure drops enough to reopen the biological valves, and the process repeats itself automatically at a rate hundreds of times per second.
Storytellers : Cornell scientists Jeffrey Dean, Associate Professor Daniel J. Aneshansley, and Professor Thomas Eisner
Story reteller: T. Ryan Gregory, Evolutionary biologist , University of Guelph, Canada.
Evolution of the Bombardier Beetle
and Bombardier Beetles and Climbing Mount Improbable
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