The amazing natural world: The Bombardier Beetle.by Don Lacey on Jun. 25, 2012, under Atheism, Campaign 2012, Christian Self-Righteous Arrogance, Creationism, Critical Thinking, Education, Environment, Ethics, Faith, God & Bible, Guns, History, Language, Libertarianism, Logic, Lying G.O.P., Materialism, Middle Class
Last year Philip “Space Museum” Olson delivered a talk on the Bombardier beetle on the Desert AIR Podcast. Here is a transcript of that presentation:
One of my absolute favorite entomologists is the late Thomas Eisner. I want to talk for a few minutes about some of the research he did and how it has been misunderstood and misrepresented by creationists. I’m talking about the Bombardier beetle and its incredible defense mechanism – the ability to spray out a boiling mixture of oxygen and chemicals known as quinones. Many species of bombardier beetle emit the substance as a thin jet which they can aim with uncanny accuracy. The beetle is able to do this through an ingenious evolutionary adaptation. It stores two precursor chemicals – hydrogen peroxide and another type of chemical called hydroquinones – in separate reservoirs in the abdomen. When the beetle feels threatened, it contracts special muscles, forcing the two chemicals into a special mixing chamber. This is when things get really cool. Inside the mixing chamber are special enzymes – catalyses and peroxidase. Oxygen is freed from the hydrogen peroxide, and the hydroquinones are then oxidized into p-quinones. There is a lot of thermal energy released during this reaction, and as the substances heat up, the internal pressure builds and the boiling mixture is expelled out the rear end of the beetle at the would-be predator or over-eager bug collector. It gets even better. Not only is the mixture boiling hot, the substances that are expelled are very irritating to almost all arthropods and most vertebrates – including people, even when they are not hot. More incredible still – this cycle of muscle contraction, chemical reaction and expulsion occurs at a rate of up to about 500 times per second.
Now, many creationists look to the bombardier beetle as proof of intelligent design. Their “evidence” seems to be based primarily on the work of Duane Gish, a biochemist who is a former vice-president of the Institute for Creation Research. Like all good creation scientists, he gets all the facts wrong. He starts off by claiming that hydrogen peroxide and hydroquinones are spontaneously explosive when combined – they are not. He claims this was a mistake he made due to a poor translation of the original research by Dr. Hermann Schildknecht, mistaking “explosive” for “unstable”. However, if Gish were truly a scientist, and not merely a creationist masquerading as one, he would have performed the simple experiment himself before repeating it so vociferously, something which should have been exceptionally easy (if not unnecessary!) for him to do as a biochemist. He also continues making a thoroughly disproved claim that an explosive “inhibitor” is required to prevent the beetle from blowing itself up. He makes the argument that the entire reaction mechanism is “irreducibly complex” and that anything less than the present form would result only in a beetle capable of blowing itself up. It’s easy to show the errors in Gish’s reasoning; we don’t even have to look into the fossil record or hypothesize intermediate stages to show that the argument of irreducible complexity simply falls flat with the bombardier beetle. He apparently overlooks the fact that the quinones, by themselves, are present in the cuticles of many different arthropods. Also overlooked is the fact that hydrogen peroxide is a by-product of cellular metabolism. A small amount of excess quinone that is left on the external cuticle would make an insect unpalatable to predators (in fact, many beetles and millipedes make use of simple quinones as defensive chemicals to avoid being eaten). There are bombardier beetles that have been found, which, instead of producing a fine jet of hot quinones, emit more of a diffuse gas, and others which produce something more akin to bubbling foam. These could be examples of beetles with lower amounts of the catalyses or peroxidase, or perhaps weaker muscles, smaller storage or mixing chambers. However you want to slice it – they are intermediate forms, all of them capable of defending themselves well enough to continue reproducing, none of them simply blowing themselves up, and so the argument of irreducibly complexity is itself reduced to nothing.
Perhaps most important in all of this is the fact that the man responsible for much of the research on bombardiers, Thomas Eisner, was himself a non-believer. He died earlier this year, of complications due to Parkinson’s disease and was an outstanding scientist, incredibly gifted science writer, pioneer of the field of chemical ecology, and one of my all time favorite authors. If you want to know more about the bombardier beetle or Thomas Eisner, I wholeheartedly recommend you find his book “For Love of Insects”.
* Charles Darwin, an avid beetle collector, recorded an experience in which he once popped a beetle into his mouth when he spotted a third beetle and already had both hands full, only to get a mouthful of a hot, irritating chemicals from the beetle