DARWIN'S BLACK BOX

Behe (Biochemistry/Lehigh Univ.) offers the thesis that biochemistry provides so many examples of ``irreducible complexity'' in nature that not even Darwinian gradualism can explain their evolution and existence. Intelligent design alone, he says, provides an answer. He then presents a modern-day version of the kinds of anti- Darwin arguments adduced a century ago: How could so intricate an organ as the vertebrate eye evolve through step-by-step chance mutations? Clearly there must be a designer at work, an eye-maker of an eye, just as there is a watchmaker for a watch. Behe's contemporary examples are a biochemistry student's nightmare: How do you make a cilium? Cilia are those fine hairs that stick out from cells lining the lungs and sweep out debris or, when attached to a bacterium, allow the bug to swim. The fine structure and molecular motors that power a cilium are awesome. And what Behe does for the cilium he does in spades in describing the biochemical events that occur when you cut yourself and a clot forms, or when your immune system takes arms against an invader. He emphasizes how each molecular actor must come on stage and go off in precise order or else the process won't work. Allusions to Rube Goldberg inventions pale by comparison. But where is it written that because science can't explain the origins of complex phenomena, the only answer is design? The history of science is replete with enigmas that have succumbed to new concepts, new tools, new paradigms. Complexity theory is in its infancy; Darwinian theory undergoes revisions departing from gradualism. Nonlinear system theory, self- organizing systems, newly discovered developmental and regulatory genes are contributing profound insights into the development of complex organs and systems. Belief that ``irreducible complexity'' implies design may comfort the faithful (Behe is a Roman Catholic), but it is neither necessary nor sufficient for many other practicing scientists.