Read Bully for Brontosaurus Online
Authors: Stephen Jay Gould
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See the postscript to this essay for an interesting reaction to this appeal.
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It is so good and pleasant, in our world of woe and destruction, to report some good news for a change. Union Station has since reopened with a triumphant and vibrant remodeling that fully respects the spirit and architecture of the original. Trains now depart from the heart of this great station, and a renaissance of rational public transportation, with elements of grand style at the termini, may not be a pipe dream.
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The proper and most accurate title of this piece should be “Tits and Clits”—but such a label would be misread as sexist because people would not recognize the reference point as
male
tits. My wife, a master at titles, suggested this alternative. (During the short heyday of that most unnecessary of all commercially touted products—vaginal deodorants—she wanted to market a male counterpart to be known as “cocksure.”)
Natural History
magazine, published by a group of fine but slightly overcautious folks, first brought out this essay under their imposed title: “Freudian Slip.” Not terrible; but not really descriptive either.
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This dreadful name has made a difficult principle even harder to grasp and understand. Preadaptation seems to imply that the proto-wing, while doing something else in its incipient stages, knew where it was going—predestined for a later conversion to flight. Textbooks usually introduce the word and then quickly disclaim any odor of foreordination. (But a name is obviously ill-chosen if it cannot be used without denying its literal meaning.) Of course, by “preadaptation” we only mean that some structures are fortuitously suited to other roles if elaborated, not that they arise with a different future use in view—now there I go with the standard disclaimer. As another important limitation, preadaptation does not cover the important class of features that arise without functions (as developmental consequences of other primary adaptations, for example) but remain available for later co-optation. I suspect, for example, that many important functions of the human brain are co-opted consequences of building such a large computer for a limited set of adaptive uses. For these reasons, Elizabeth Vrba and I have proposed that the restrictive and confusing word “preadaptation” be dropped in favor of the more inclusive term “exaptation”—for any organ not evolved under natural selection for its current use—either because it performed a different function in ancestors (classical preadaptation) or because it represented a nonfunctional part available for later co-optation. See our technical article, “Exaptation: A Missing Term in the Science of Form,”
Paleobiology
, 1981.
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This parenthetical comment inspired Roger Angell’s letter and led directly to research and writing of the essay preceding this piece.
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I thank Gerald A. Le Boff and Ernest F. Marmorek for informing me, after reading this essay at its initial publication, of another explicit link between Mozart (and his great librettist, DaPonte) and Mesmer. In
Cost Fan Tutte
, the maid Despina, disguised as a physician, “cures” Ferrando and Guglielmo of their feigned illness by touching their foreheads with a large magnet and then gently stroking the length of their bodies. An orchestral tremolo recalls the curing mesmeric crisis, while Despina describes her magnet as:
pietra Mesmerica
ch’ebbe l’origine
nell’ Alemagna
che poi si celebre
lá in Francia fù.
—a mesmeric stone that had its origin in Germany and then was so famous in France (a fine epitome of Mesmer’s tactic and its geographic history).
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To throw in a tidbit for readers interested in the history of evolutionary theory, this tightly coordinated complex of larval adaptations so intrigued Richard Goldschmidt that he once wrote an entire article to argue that light, carnivory, and nest building could not have arisen by gradual piecemeal, since each makes no sense without the others—and that all, therefore, must have appeared at once as a fortuitous consequence of a large mutational change, a “hopeful monster,” in his colorful terminology.
This proposal (published in English in
Revue Scientifique
, 1948) inspired a stern reaction from orthodox Darwinians. Although I have great sympathy for Goldschmidt’s iconoclasm, he was, I think, clearly wrong in this case. As J. F. Jackson pointed out (1974), Goldschmidt made an error in the taxonomic assignment of
A. luminosa
among the Mycetophilidae. He ranked this species in the subfamily Bolitophilinae. All larvae of this group burrow into soft mushrooms, and none shows even incipient development of any among the three linked features that mark the unique form and behavior of
A. luminosa
. Hence, Goldschmidt argued for all or nothing.
But
A. luminosa
probably belongs in another subfamily, the Keroplatinae—and, unknown to Goldschmidt, several species within this group do display a series of plausible transitions.
Leptomorphus
catches and eats fungal spores trapped on a sheetlike nest slung below a mushroom. Some species of
Macrocera
and
Keroplatus
also build trap nets for fungal spores but will eat small arthropods that also become ensnared. Species of
Orfelia, Apemon
, and Platyura build webs of similar form but not associated with mushrooms—and they live exclusively on a diet of trapped insects. Finally,
Orfelia aeropiscator
(literally, air fisher) both builds a nest and hangs vertical feeding threads but does not possess a light.
These various “intermediates” are, of course, not ancestral to
A. luminosa
. Each represents a well-adapted species in its own right, not a transitional stage to the threefold association of New Zealand glowworms. But this array does show that each step in a plausible sequence of structurally intermediate stages can work as a successful organism. This style of argument follows Darwin’s famous resolution for a potential evolutionary origin for the extraordinary complexity of the vertebrate eye. Darwin identified a series of structural intermediates, from simple light-sensitive dots to cameralike lens systems—not actual ancestors (for these are lost among nonpreservable eyes in a fossil record of hard parts) but plausible sequences disproving the “commonsense” notion that nothing in between is possible in principle.
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After writing this essay, I visited the cathedral of San Marco in Venice, and was pleased to note that the early medieval mosaics of the great creation dome (in the south end of the narthex) picture the events of the first six days as an explicit sequence of divisions with differentiation.
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This essay originally appeared in the
New York Review of Books
as a review of Michael Seidel’s
Streak: Joe DiMaggio and the Summer of 1941
(New York: McGraw-Hill, 1988). I have excised the references to Seidel’s book in order to forge a more general essay, but I thank him both for the impetus and for writing such a fine book.
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When I wrote this essay, Frank Robinson, the Baltimore skipper, was the only black man at the helm of a major league team. For more on the stats of Baltimore’s slump, see my article “Winning and Losing: It’s All in the Game,”
Rotunda
, Spring 1989.
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So far so good.
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Since writing this, my death has actually been reported in two European magazines, five years apart.
Fama volat
(and lasts a long time). I squawked very loudly both times and demanded a retraction; guess I just don’t have Mr. Clemens’s
savoir faire
.
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Several Southern Hemisphere colleagues wrote to protest the indefensible parochialism of this image. The solar system has no natural “above” or “below.” We think of the Northern Hemisphere as “above” only by cartographic convention in the Eurocentric tradition. I could have silently changed my restrictive image, but elected this correction by footnote since the illustration of such parochialism, however embarrassing, always serves to illustrate the power of unconscious bias and the need for continuous self-scrutiny.