Thursday, November 10, 2011

Dinosaur in a Haystack, by Stephen Jay Gould, a review.

How better to summarize this 1995 book by paleontologist and science historian Stephen Jay Gould than simply to say, " 34 Natural History Essays, 460 pages, with a valuable Index and Bibliography ranging from William Blake and both Bacons (Sir Francis of Elizabethan science and Roger the contemporary painter), Humphrey Bogart, P.T. Barnum, Lewis Carroll, Anton Chekhov and Noam Chomsky, to Lord Bertrand Russell, Oliver Sacks, Mary Shelley, Voltaire, and E.O. Wilson. Not to mention the scientists!

Gould, professor at Harvard and NYU, curator and important theorist himself in evolutionary science, was all his life engaged in an effort to eradicate the chasm between science and social understanding, or between academic and intellectual discourse and the rest of "us." His concern is always to eradicate faulty or downright false ideas about science in general and evolution most particularly. He constructs graceful, often humorous, but meticulous arguments about important ideas, starting from a detail, e.g., a historical event, a curious happenstance in the life of some artist, politician, or scientist, or even sports star, and leading with precision to general conclusions and theories.

        Take, for example, one essay which is going to be deadly serious and worrisomely abstract about the debate between Gradualism (or Uniformitarianism) and Catastrophism (or Punctuated Equilibrium, as one of Gould's major scientific theories has it). But Gould doesn't start talking in the abstract or scientific jargon: he starts with some innocuous and amusing remarks on "Tongue Worms, Velvet Worms, and Water Bears." Illustrations of these eerie tiny creatures add greatly to the interest; one species is aptly called Hallucigenia. Gould leads the reader gently around to the fact that some scientists have cited these creatures as arguments against the Cambrian Explosion. And here we are embarking on geology and paleontology and the history of life, but carried along by little living fantasias to provoke the curiosity and by transparent prose. What is the Cambrian Explosion? A geologically brief time (a mere 5 million years!) nearly 550 million years ago. What exploded? Life! Most major groups of today's creatures first appear in discernible fossils during that "explosion" of life forms.

       Gradualists find it unlikely that this all happened so (relatively) fast. It goes against the grain of almost unconscious expectation of uniform and gradual changes. Gould, the original 20th-century "catastrophist" in a way (and I oversimplify) is delighted therefore to share new data that uses Tongue Worms et al. to affirm the Cambrian Explosion.The argument against it cited the Tongue Worm phylla as representative of most early life in that it was soft-bodied so we couldn 't know much about origins because of course there aren't fossils before the Cambrian Explosion because soft bodies wouldn't leave fossils. So maybe the phylla of Tongue Worms evolved well after the supposed burst. But a new method for identifying the presence of "shell-less bone-less chicken-less eggs" found that these weird tiny creatures did, in fact, first occur during that 5-million-year episode of "Let there be (multi-celled) life!" Can you imagine the intellectual satisfaction of actually following this elucidation?

       Dinosaur in a Haystack takes its name from a curious phenomenon, that of not finding Dinosaur fossils where they were not really expected to be. A common theme of Gould's penetrating essays on the interaction of social gestalts and scientific theories is that finding anything requires, first, the capacity to imagine that the thing exists somewhere, and, second, the ability to predict where to look. Plus, the third, a conviction that one must look painstakingly. The proverbial needle in the haystack is impossible to find in a casual search, especially if the searcher is not really sure there is one. Once the search is motivated by expectation of value and an image of what is being sought, then it makes sense to take apart the haystack straw by straw, with the inevitable result that if it's there it will be found.

       The particular example here of missing dinosaurs is part of a six-essay centerpiece under the general title "Origin, Stability, and Extinction." All six deal with the problem of expectations, the difficulty of theoretical changes, and how changing expectations or models then begin to yield new results. The dinosaur example figures in a discussion of the once ridiculous suggestion that a large meteor or part of a comet "struck the earth at the end of the Cretaceous period, sixty-five million years ago, triggering one of the five great mass extinctions of life's history," the one which killed all, yes, all dinosaurs. Gould notes that when Nobel-winning physicist Luis Alvarez and colleagues including his son Walter, Helen Michel and Frank Asaro, "first proposed their radical hypothesis of catastrophic extinction," it was met with rejection, containing both "ridicule and vehemence."

       Beyond the general difficulty of accepting such a new and unheard-of proposition, the hypothesis entailed a larger and more general historical debate in evolutionary science: the above-mentioned Gradualism vs. Catastrophism. The Alvarez hypothesis was announced in 1979, coincidentally only a few years after Gould himself and colleague Niles Eldredge had staked their young careers on publication of an anti-gradualist thesis in "Punctuated Equilibria" (1972). Most paleontologists, however, argued that although the dinosaurs became extinct over a period of time toward the end of the Cretaceous era, there was literally no evidence that they had all died in such a short period as would be caused by a single event. And what kind of event could possibly affect the whole globe so quickly?
       Part of the hold of Gradualism is that it allows for the myth that all of life has been evolving naturally toward the creation of the ideal creature, the highest and most complex creature, our humble selves. If catastrophes actually figure significantly in evolution, then the role of chance, of contingency and specific histories, would argue against steady advancement toward improvement. Nevertheless evidence began to accrue to support the Collision thesis: some of it geographical—a crater off the Mexican Yucatan; some of it mineralogical—involving unusually high concentrations of a mineral rare in indigenous earth, and "shock crystals" or "shocked quartz." So scoffing paleontologists were challenged—either to find or definitively not-find-- fossil evidence.

       The argument that dinosaurs died off gradually, over a long period of geological time, was based on the way fossils seemed harder and harder to find in strata over a long era. There were no dinosaurs right up to the very edge of the supposed "cataclysm," so they were already all gone by then, supposedly. A determined search, straw by straw, as it were, was made in order to prove that the dinosaur fossils disappeared before the sudden "end" of the era which would coincide with a cataclysmic event. When the later strata of formations were gone through, "straw by straw," the various scientists issued graceful acknowledgment of defeat: "there is no significant change (in occurrence) between the lower, middle, and upper thirds of the formation. . . .These findings are consistent with an abrupt extinction scenario." The "missing" dinosaur remains were found, after all.

       Finally, in 1994 there was visual confirmation of what an asteroid might do to a planet when the Shoemaker-Levy comet fragments bombarded Jupiter. One fragment produced "a fireball that exceeded the brightness" of the entire planet, and a gas plume some 1300 miles in height. Fragment G, the largest, was only about 2.0 to 2.5 miles in diameter. The Cretaceous-ending object was 6.0 miles across. Doubters became believers as the physics of planetary impact were vividly demonstrated.

       Cultural paradigms die slowly, often agonizingly, for societies and for individuals. To change the very framework through which we view the world is wrenching and disorienting. Imagine today how many fundamentalists—with no science training and relying only on popular, often distorted impressions of evolutionary theory—simply cannot bear to contemplate what seems to them only a wild and unsupported theory which would (again, in the popular distortions of evolution) honor only the bestial in human beings, deny divine agency, contradict their religious foundations and endorse cruel competition, chaotic mayhem. Even if one is not a Christian fundamentalist, I think one needs a strong science background to resist the image that Social Darwinism seems still to project as justification for the worst excesses of dog-eat-dog corporate capitalism. (See new book by Robert H. Frank, The Darwin Economy ! Ox-pucky!)

       There are also essays here on re-visioning what is right in front of us, partly because of new technology, but also because of slowly shifting paradigms. For instance, scientists can now conceive of asking whether a thirty-acre fungus is to be granted status as an individual? And since female aphids—dare we call them mothers?—can generate up to a billion little aphids parthenogenetically (i.e., without sexual fertilization), are these offspring individuals, or clones, or can clones be individuals? At last, it seems scientists are coming around to my way of thinking (I say this only partially in jest, as a Buddhist in philosophy and practice with its vision of being/not-beging "one with everything") and beginning to loosen rigid culturally biassed definitions of individuality. Nineteenth-century science, confined and defined as it was in Europe, was not likely to notice or consider any alternative definition of individuals as long as the model or ideal "progressive" society was one in which the individualist end of the continuum was obviously either God's idea or the idea that had replaced God.

       Perhaps even thirty or twenty years ago a question of the individuality of a vast fungus would have been considered out of bounds. For one thing, what could be the "test" or "evidence" of individuality? Thus the organic complexity of a fungus was left in limbo, but believed to be completely different from the social sense of individuality. In fact, the "Humongous Fungus Among Us" (Gould) was a bit scary ideologically, simply too much like Star Trek's Borg, a cancerous envelopment of individuals who thereby lost their separate beings and were subservient to the oppressive "commune." In the sauve qui peut mindset of nineteenth and early twentieth century, "separation" and "individuation" literally defined the progressive and fully matured individual. From this perspective scientists and philosophers (and psychologists) argued that social insects are not individuals; they have no individual freedom. (See my review of Dorothy Sayers' Lord Peter mystery, Whose Body? and reference to "a few backward individuals.")

       Genetic science has been a major factor in shifting science's purview. And now (perhaps) the fungus is an individual, by genetic analysis. The aphid clone is—a clone of perhaps a billion. All right, billion individuals. Bees and ants are individuals even without individual competition to leave the most (personal) progeny. It seems whenever males are not the kings of a portion of creation, and I am talking of the negligibility of the males in ants, bees and aphids, the Buddhist principle of interbeing is given more room to reverberate. Fish who change gender to suit the needs of the school!! Medusas, or other kinds of jellies, which are individuals without a single brain and without benefit of sexual reproduction, being made up of a big cohort of sisters, or a consort of sorority? I'm straying from Gould here, but no wonder.

       I tell you, this evolution/paleontology/biology/science stuff is a gas. And Gould, -- well, he's a mine, from which we derive pure energy. Elegant, thorough, coherent, articulate, and (usually) clear and graceful. This 1995 book is a little on the self-indulgent side of his work, it seems to me, but still: these collections of his Natural History columns are readable, literate, often humorous, and always food for serious thought. Even for non-scientists. Like me.  By the way, the anti-gradualist essay was reprinted in book form in 2007 as
Punctuated Equilibrium.  Readable.  Even for non-scientists. Yes, like me.