Drafting the Bombardier Beetle ^

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They are locked in unlikely combat, and no truce is in sight. On one side are the scientists, who have amassed such overwhelming geological, paleontological and biological evidence that evolution has shaped the course of life on earth that they take the theory for granted, sort of like the law of gravity. On the other side are the creationists, who apply the language but not the rigor of science to defend a literal interpretation of Genesis. As the creationists see it, the universe and solar system were born only 10,000 years ago, humans trod the earth in the company of hulking dinosaurs, and evolution is a false idol. Although they have lost legal battles in Arkansas, Texas and most recently Louisiana to require their teachings in public school biology classes, the creationists continue their attack against evolution. For their latest foray, they have enlisted the aid of a favored if surprising ally: the bombardier beetle, a half-inch insect found near streams and ponds around the world. Their case is presented in a new book for children titled Bomby, the Bombardier Beetle, published by the Institute for Creation Research in El Cajon, Calif. Author Hazel May Rue, a retired schoolteacher, argues that the nature of the diminutive creature's defenses proves that it could not have evolved. It must have first appeared in its present form, she maintains, carefully prefabricated by God.

At first glance, the bombardier does appear to be unique in the animal kingdom. Its defense system is extraordinarily intricate, a cross between tear gas and a tommy gun. When the beetle senses danger, it internally mixes enzymes contained in one body chamber with concentrated solutions of some rather harmless compounds, hydrogen peroxide and hydroquinones, confined to a second chamber. This generates a noxious spray of caustic benzoquinones, which explodes from its body at a boiling 212 degreesF. What is more, the fluid is pumped through twin rear nozzles, which can be rotated, like a B-17's gun turret, to hit a hungry ant or frog with bull's-eye accuracy. When Rue learned about the bombardier, she says, "I fell in love with him."

Her thin tome lays out the creationist views in the form of stories a father beetle tells his son Bomby about the ways of the bombardier family. The text is peppered with scientific terms like amino acids and catalase, but it is so riddled with errors that entomologists cannot begin to guess where Rue got her information. (For example, the beetles do not spray their eggs with tear gas for protection, as the author maintains.) Biologist Thomas Eisner of Cornell University, one of the world's leading bombardier experts, says of the book, "I've never seen anything like it."

In Bomby, as well as in The Plain Truth, a fundamentalist magazine, creationists argue the beetle could not possibly have evolved separate chambers of chemicals that, in the event of a genetic misstep, would have blown the insect up. A prominent member of the Institute for Creation Research, Duane Gish, who holds a doctorate in biochemistry from the University of California, Berkeley, contends the beetle would not have any use for its storage, temperature and aiming facilities until they were completely formed. Says he: "I would challenge Dr. Eisner to sketch out how an ordinary beetle could evolve into a bombardier beetle. I want to know how natural selection has done that."

In fact, Eisner had considered the matter long before that gauntlet was thrown down. To begin with, he says, "the bringing together of appropriate chemicals at appropriate times is the basis of all biology. It's as old as life itself." So why single out the bombardier for harboring dangerous chemicals in its body? he asks. Why not the human digestive tract, for example? There the stomach walls are protected from the hydrochloric acid within by a layer of mucus, which, if damaged, would allow the potent acid to attack the stomach walls and be released into the body.

Going further, Eisner points out that none of the bombardier's chemicals are unique to the insect. Hydrogen peroxide is often a by-product of metabolism in the cell. Phenols, the chemical group to which hydroquinones belong, are employed by many plants and primitive animals to heal and disinfect wounds. "The beetle didn't invent anything," says Eisner. "It just found novel uses for existing elements."

Even in producing its separate chambers, Bomby did nothing extraordinary. It descended from a family of ground beetles that have single internal chambers and merely added the second compartment by subdividing the first. Eisner also offers strong evidence, in the form of "living fossils," that the bombardier did indeed evolve: proto-bombardiers have been found in Africa, California and Australia. One of the variations that he has studied can spray a burst of benzoquinones, but it lacks the bombardier's aiming mechanism and ends up with a repellent froth on its back. The bombardier's nozzle arrangement is obviously a refinement of this type of defense. Says Eisner: "This is evolution right before your eyes."

Having contributed to what he thinks is compelling evidence confirming that Bomby evolved, Eisner sees no reason to choose Darwin at the expense of God. Says he: "Why not think of a supreme deity who devised the scheme of evolution?"