Odd Jobs
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Gould’s evangelical sense of science as an advancing light gives him a vivid sympathy with thinkers in the dark. The great Lord Kelvin, the discoverer of the second law of thermodynamics, for forty years proposed ages of the earth and sun too brief to allow organic evolution; but, then, how could anyone calculate the sun’s thermal life before the discovery of radioactivity and nuclear fusion? How could the energetic debates over embryology carried on in eighteenth-century France, by such savants as Pierre-Louis Moreau de Maupertuis, be less than grotesquely simple-minded two centuries before DNA was analyzed, and fifty years before the jacquard loom offered the first analogous instance of programmed instructions? Science not only produces technology but must wait upon it. We forget how tangled things looked to those who first tried to sort them out; as the record of the strata emerged, catastrophism (which is now having a revival of sorts) was the logical conclusion to reach, as Gould has pointed out in an essay on Georges Cuvier:
In the great debates of early-nineteenth-century geology, catastrophists followed the stereotypical method of objective science—empirical literalism. They believed what they saw, interpolated nothing, and read the record of the rocks directly. This record, read literally, is one of discontinuity and abrupt transition: faunas disappear; terrestrial rocks lie under marine rocks with no recorded transitional environments between; horizontal sediments overlie twisted and fractured strata of an earlier age.
Gould chastens us ungrateful beneficiaries of science with his affectionate and tactile sense of its strenuous progress, its worming forward through fragmentary revelations and obsolete debates, from relative darkness into relative light. Even those who were wrong win his gratitude.
In a day of perhaps excessively professional and instrumentalized research, Gould loves with the ardor of a boyish amateur the dispassionate scientific method. This method, he keeps insisting, must be resolutely non-mystical and isolated from human wishful thinking—what he several times calls “hope.” “Always be suspicious of conclusions that reinforce uncritical hope and follow comforting traditions of Western thought,” he writes in a discussion of the “anthropic principle,” which is a new name for the venerable human idea that things must have been designed for us, since here we are. It has taken new life lately from the realization of what extremely fine balances were apparently struck among the fundamental physical forces to provide a universe as stable and locally congenial as it is; but an earlier version was advanced in 1903 by Alfred Russel Wallace, who ranks alongside Darwin in the discovery of natural selection but who later drifted, unlike the ever-empirical Darwin, into spiritualism and anthropocentricism. Wallace, working with turn-of-the-century astronomy, demonstrated to his own satisfaction that “the marvellous complexity of forces which appear to control matter, if not actually to constitute it, are and must be mind-products.” Mark Twain ridiculed Wallace’s thesis (“According to these figures, it took 99,968,000 years to prepare the world for man, impatient as the Creator doubtless was to see him and admire him”) and Gould tartly says of it, “I, for one, will seek my hope elsewhere.” He does not say where, unless it be in the hope of ever-newer scientific ideas.
Though a devout disciple of Darwin, he is no slave to the gradualism that Darwin conceived to be the pace of adaptation and that makes the larger steps of evolution very hard to picture. Gould has written on, and written a new introduction to, the geneticist Richard Goldschmidt’s controversial The Material Basis of Evolution (1940), which argues that, though Darwin’s gradualism satisfactorily accounts for, say, the prevalence of white rabbits in snow country, the large mutations can only be explained by the hypothesis of the “hopeful monster”—the rare freak whose malformation has a survival value and who finds (here’s a rub) another hopeful monster to mate with. Gould has offered, as a way of coping with the embarrassments of discontinuity in the paleontological record, a theory of “punctuated equilibria” that has, to his annoyance, given some comfort to creationists. As the last essays in The Flamingo’s Smile show, he is considerably excited by the recent so-called Nemesis hypothesis, which holds that mass extinctions have been caused every twenty-six million years by the return of a star that comes close enough to the solar system to stir up the Oort cloud of comets and thus precipitate collisions and climate-altering dust-storms on earth. This might be called catastrophism with a heavenly face.
As he sifts through biological riddles, however, whether in the fossil record (conodonts, the banana-shaped Tullimonstrum, the pre-Cambrian Ediacaran fauna) or the living world (sexual cannibalism among insects, sequential hermaphroditism in Crepidula, identity problems in Siamese twins and Portuguese men-of-war), or fends off cladists and creationists, advocates of eugenics and of the anthropic principle, Gould has Darwin’s example ever before him. He has read the books Darwin wrote in addition to the two notorious ones, On the Origin of Species and The Descent of Man (1871), and has written separate essays on The Formation of Vegetable Mould, Through the Action of Worms, with Observations on Their Habits (1881) and On the Various Contrivances by Which British and Foreign Orchids Are Fertilized by Insects (1862). Patient and scrupulous observation are as important to the naturalist as worms and pollination are to nature; Darwin’s slowness to generalize and the detailed concreteness with which he substantiated his generalizations are of a piece with his unique powers of insight into the workings of nature. The proper observer must not be hasty to impose order, or to demand too much neatness of nature. Gould frequently delights in nature’s intricate dishevelment, in the waywardness of adaptation:
Our world is not an optimal place, fine tuned by omnipotent forces of selection. It is a quirky mass of imperfections, working well enough (often admirably); a jury-rigged set of adaptations built of curious parts made available by past histories in different contexts. Darwin, who was a keen student of history, not just a devotee of selection, understood this principle as the primary proof of evolution itself.
The word “evolution,” with its connotation of onrolling or progressive development, was not favored by Darwin; he preferred for his theory the bleak string-phrase “descent with modification through variation and natural selection.” The pure fortuitousness and physicality of nature’s workings must not be polluted, Gould reaffirms, by human thought-habits or wishful thinking. “The human mind delights in finding pattern—so much so that we often mistake coincidence or forced analogy for profound meaning. No other habit of thought lies so deeply within the soul of a small creature trying to make sense of a complex world not constructed for it.” To lock out old notions of divine planning and human singularity, the notions of randomness and fortuity and contingency are stressed as if themselves sacred: “Random processes do produce high degrees of order—and the existence of pattern is no argument against randomness.” The shattering effect Darwin’s theory had upon the Victorians did not concern its allegations of “nature red in tooth and claw,” to which every farmer and soldier could already attest, but, rather, its description of how intricate organic design would arise without any divine intention. “Evolution,” Gould stated with relish in the prologue to his first collection, “is purposeless, nonprogressive, and materialistic.” In the essay upon Darwin’s worm studies, he cited as exemplary “the materialistic character of Darwin’s theory, particularly his denial of any causal role to spiritual forces, energies, or powers.” Even such a mild, almost furtive suggestion of the supernatural as vitalism’s hint that there exists in life a “spark” or “special something” must be rejected—even the plausible notion that Homo sapiens’s high intelligence crowns an evolutionary trend. “Human brains and bodies did not evolve along a direct and inevitable ladder, but by a circuitous and tortuous route carved by adaptations evolved for different reasons, and fortunately suited to later needs.”
Mammals developed in size and capability because, in large part, the dinosaurs died out. But, one wonders, might not reptiles have developed superior intelligences? Gould’s own essay “Were Dinosaurs Dumb?�
� discusses small, flesh-eating, necessarily quick and agile dinosaurs, such as Stenonychosaurus, heading in this direction. Is not intelligence so formidable a weapon for survival as to develop inevitably? In the sea, are not the cetaceans—the whales, porpoises, and dolphins—its newest considerable citizens and also its brightest? Gould does not entertain these questions, asserting instead that “Conscious intelligence has evolved only once on earth, and presents no real prospect for reëmergence should we choose to use our gift for destruction.” This closed outlook comes oddly from the man who marvelled at how the panda, needing a thumb to grip his bamboo shoots, evolved one from a wrist bone, or who points out how flight has evolved four times on earth, the wing derived each time from different body elements. Gould regards human intelligence as in the same class—ornately evolved oddity—as the flamingo’s upside-down beak, which gives him his title. Our brains are a kind of unintended smile on the surface of the bellum omnium contra omnes—the war of all against all, as Marx called Darwin’s nature. A stark view, but a lucid and, it would appear, an invigorating one. As a constant writer (who has not in ten years, he tells us, missed a deadline), Stephen Gould is fortunate to possess an approach and a theme that cast a clarifying light upon such a wide variety of facts and texts. He is additionally fortunate in having, in Darwin, a hero to serve as a point of reference and a standard of honor.
Deep Time and Computer Time
TIME’S ARROW, TIME’S CYCLE: Myth and Metaphor in the Discovery of Geological Time, by Stephen Jay Gould. 222 pp. Harvard University Press, 1987.
TIME WARS: The Primary Conflict in Human History, by Jeremy Rifkin. 263 pp. Holt, 1987.
European man, who once dwelt with a certain unsanitary snugness on a flat world hedged in by Vikings and Saracens and enclosed by the chiming celestial spheres, has suffered a series of traumatic widenings of consciousness. First—and perhaps least unnerving, since it was accompanied by triumphs of conquest and trade—was the increased awareness of the earth’s actual geography, as Italian merchants, Portuguese sailors, Spanish conquistadores, and British explorers brought back word of the vast Asian landmass, the long African coast, the two unsuspected continents of the New World, the watery vastness of the Pacific Ocean, and the icebound polar regions. Then there was astronomy, which showed the fixed nightcap of stars with its seven “wanderers” (the sun, the moon, and the five observable planets) to be the visible fraction of unthinkable extents of space and energy. The Copernican revolution removed the earth from the center of the universe but did not alter its scale; this the telescope, first used astronomically by Galileo, was to enlarge inexorably, until in the 1920s Edwin Hubble demonstrated that our Milky Way, with its billions of stars, was but one of countless galaxies, which are generally flying from one another like shrapnel in a gargantuan explosion. In the direction of the small, lenses, as microscopes were developed in the seventeenth century, revealed a teeming sub-world of animalcula and microbes, beneath which lay an even finer world of molecules, atoms, and subatomic particles—dizzying depths of active complexity beyond the reach not only of the eye but of all direct observational apparatus. And in the dimension of time another abyss was uncovered by the geological sciences, whose early theorists include Leonardo and Descartes: by the late eighteenth century it had become clear that only huge amounts of elapsed time could account for the stratified, folded, eroded, fossiliferous state of the earth’s rocks, which the Bible had declared to have been created only at the outset of its own historical record, in a year calculated to have been 4004 B.C.
The blasphemous and dwarfing revelation of “deep time” forms the underlying drama of Stephen Jay Gould’s Time’s Arrow, Time’s Cycle: Myth and Metaphor in the Discovery of Geological Time. In the monthly essays with which Gould has been amusing and edifying the readers of Natural History magazine, he now and then shows a surprisingly fond acquaintance with the debunked and forgotten theories that litter the history of science: the present book, an expanded version of lectures given at Hebrew University in Jerusalem, considers three early British geologists—Thomas Burnet (1635–1715), James Hutton (1726–1797), and Charles Lyell (1797–1875)—who he feels have been misrepresented in the contemporary textbook version of geology’s progress. In “textbook cardboard,” this progress is represented as the “victory of superior observation finally freed from constraining superstition”—the supplanting, that is, of fanciful, religion-tainted theories by the patient field work and inductive reasoning of true scientists. Yet, Gould argues, “scientists are not robotic inducing machines that infer structures of explanation only from regularities observed in natural phenomena.… Scientists are human beings, immersed in culture, and struggling with all the curious tools of inference that mind permits—from metaphor and analogy to all the flights of fruitful imagination that C. S. Peirce called ‘abduction.’ ”
Among the cultural metaphors that shaped the searching out of deep time are those of time’s arrow and time’s cycle. Did the enigmatic evidence of the rocks show that the earth had a history proceeding from a beginning to an end, or was its geology a matter of endless cycles of erosion and repair, subsidence and uplift? The truth, Gould says, lies with both: the cycles move along an arrow. And Burnet, the textbook-deplored proponent of the Bible-inspired Sacred Theory of the Earth (1680–89) came closer to this double truth than Hutton’s Theory of the Earth (first publication 1788) and Lyell’s Principles of Geology (first edition 1830–33). “Hutton and Lyell, traditional discoverers of deep time in the British tradition, were motivated as much (or more) by … a vision about time, as by superior knowledge of the rocks in the field.… Their visions stand prior—logically, psychologically, and in the ontogeny of their thoughts—to their attempts at empirical support.” Hutton, to be more precise, was so much under the sway of Newton’s magnificent analysis of heavenly motion as to impose a similarly perpetual and ideal mechanics upon geology, and Lyell was so caught up in his combat with the “catastrophists” on behalf of “uniformitarianism” as to ignore, until late in his life, the fact that earth’s fossils do trace an irreversible history, and that strata of rock can be ordered by them.
If this sounds technical, it somewhat is. But geology has the charm that we all walk upon its raw material, and Gould’s lucid, animated style, rarely slowed by even a touch of the ponderous,† leads us deftly through the labyrinth of faded debates and preconceptions. His own contemporary engagement in the debate with evolutionary “gradualists” opposed to his and Niles Eldredge’s theory of “punctuated equilibrium” lends verve to his exposition of old points of contention. Though gradual change, operating through great tracts of time, is now assumed to be the empirically proven mode of biological and evolutionary change, the evidence, Gould takes some pleasure in reminding us, favored and still favors the catastrophists:
Read literally, then and now, the geological record is primarily a tale of abrupt transitions, at least in local areas. If sediments indicate that environments are changing from terrestrial to marine, we do not usually find an insensibly graded series of strata, indicating by grain size and faunal content that lakes and streams have given way to oceans of increasing depth. In most cases, fully marine strata lie directly atop terrestrial beds, with no signs of smooth transition. The world of dinosaurs does not yield gradually to the realm of mammals; instead, dinosaurs disappear from the record in apparent concert with about half the species of marine organisms in one of the five major mass extinctions of life’s history. Faunal transitions, read literally, are almost always abrupt, both from species to species and from biota to biota.