Darwin Without Darwinism
BIOLOGISTS OFTEN affirm that as members of the scientific community they positively welcome criticism. Nonsense. Like everyone else, biologists loathe criticism and arrange their lives so as to avoid it. Criticism has nonetheless seeped into their souls, the process of doubt a curiously Darwinian one in which individual biologists entertain minor reservations about their theory without ever recognizing the degree to which these doubts mount up to a substantial deficit. Creationism, so often the target of their indignation, is the least of their worries.
For many years, biologists have succeeded in keeping skepticism on the circumference of evolutionary thought, where paleontologists, taxonomists, and philosophers linger. But the burning fringe of criticism is now contracting, coming ever closer to the heart of Darwin’s doctrine. In a paper of historic importance, Stephen Jay Gould and Richard Lewontin expressed their dissatisfaction with what they termed “just-so” stories in biology.(8)
It is by means of a just-so story, for example, that the pop biologist Elaine Morgan explains the presence in human beings of an aquatic diving reflex. An obscure primate ancestral to man, Morgan argues, was actually aquatic, having returned to the sea like the dolphin. Some time later, that primate, having tired of the water, clambered back to land, his aquatic adaptations intact. Just so.
If stories of this sort are intellectually inadequate–preposterous, in fact–some biologists are prepared to argue that they are unnecessary as well, another matter entirely. “How seriously,” H. Allen Orr asked in a superb if savage review of Dennett’s Darwin’s Dangerous Idea, should we take these endless adaptive explanations of features whose alleged Design may be illusory? Isn’t there a difference between those cases where we recognize Design before we understand its precise significance and those cases where we try to make Design manifest concocting a story? And isn’t it especially worrisome that we can make up arbitrary traits faster than adaptive stories, and adaptive stories faster than experimental tests?
The camel’s lowly hump and the elephant’s nose–these, Orr suggests, may well be adaptive and so designed by natural selection. But beyond the old familiar cases, life may not be designed at all, the weight of evolution borne by neutral mutations, with genes undergoing a slow but pointless drifting in time’s soft currents.
Like Orr, many biologists see an acknowledgment of their doubts as a cagey, a calculated, concession; but cagey or not, it is a concession devastating to the larger project of Darwinian biology. Unable to say what evolution has accomplished, biologists now find themselves unable to say whether evolution has accomplished it. This leaves evolutionary theory in the doubly damned position of having compromised the concepts needed to make sense of life–complexity, adaptation, design – while simultaneously conceding that the theory does little to explain them.
NO DOUBT, the theory of evolution will continue to play the singular role in the life of our secular culture that it has always played. The theory is unique among scientific instruments in being cherished not for what it contains, but for what it lacks. There are in Darwin’s scheme no biotic laws, no Bauplan as in German natural philosophy, no special creation, no elan vital, no divine guidance or transcendental forces. The theory functions simply as a description of matter in one of its modes, and living creatures are said to be something that the gods of law indifferently sanction and allow.
“Darwin,” Richard Dawkins has remarked with evident gratitude, “made it possible to be an intellectually fulfilled atheist.” This is an exaggeration, of course, but one containing a portion of the truth. That Darwin’s theory of evolution and biblical accounts of creation play similar roles in the human economy of belief is an irony appreciated by altogether too few biologists.
Notes
A.S. Romer’s Vertebrate Paleontology (University of Chicago Press, third edition, 1966) may be consulted with profit.
The details have been reported in the New York Times and in Science: evidence that at least some entomologists have a good deal of time on their hands.
Schutzenberger’s comments were made at a symposium held in 1966. The proceedings were edited by Paul S. Moorhead and Martin Kaplan and published as Mathematical Challenges to the Neo-Darwinian Interpretation of Evolution (Wistar Institute Press,1967). Schutzenberger’s remarks, together with those of the physicist Murray Eden at the same symposium, constituted the first significant criticism of evolutionary doctrine in recent decades.
Murray Eden is, as usual, perceptive: “It is as if,” he writes “some pre-Newtonian cosmologist had proposed a theory of planetary motion which supposed that a natural force of unknown origin held the planets in their courses. The supposition is right enough and the idea of a force between two celestial bodies is a very useful one, but it is hardly a theory.”
Black Mischief: Language, Life, Logic & Luck (1986).
The same pattern of intellectual displacement is especially vivid in Daniel Dennett’s description of natural selection as a force subordinate to what he calls “the principle of the accumulation of design.” Sifting through the debris of chance, natural selection, he writes, occupies itself by “thriftily conserving the design work . . . accomplished at each stage.” But there is no such principle. Dennett has simply assumed that a sequence of conserved advantages will converge to an improvement in design; the assumption expresses a non sequitur.
It is absurdly easy to set up a sentence-searching algorithm obeying purely Darwinian constraints. The result, however, is always the same–gibberish.
“The Spandrels of San Marco and the Panglossian Paradigm: A Critique of the Adaptationist Programme,” Proceedings of the Royal Society. Volume B 205 (1979).
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