They are correct that punctuated equilibria apply to sexually reproducing organisms and that morphological evolutionary change is regarded as largely (if not exclusively) correlated with speciation events. However, they err in suggesting that we attribute stasis strictly to "developmental constraints," which represent only one of a set of possible mechanisms that we have suggested for the causes of stasis. Others include habitat tracking and the internal structure of species themselves [for example, (2)].
FEW HEROES LOWER their sights in the prime of their lives; triumph leads inexorably on, often to destruction. Alexander wept because he had no new worlds to conquer; Napoleon, overextended, sealed his doom in the depth of a Russian winter. But Charles Darwin did not follow the Origin of Species (1859) with a general defense of natural selection or with its evident extension to human evolution (he waited until 1871 to publish The Descent of Man). Instead, he wrote his most (...) obscure work, a book entitled: On the Various Contrivances by Which British and Foreign Orchids Are Fertilized by Insects (1862). (shrink)
l i ver Cromwell delivered history's most famous rebuke to the heroworshiping that irons all subtlety into flawless cardboard: Mr. Lely, I desire you would use all your skill to paint my picture truly like me, and not flatter me at al l ; but remark all these roughnesses, pimples, warts, and everything as you see me, otherwise I will never pay a farthing for it. Helena Cronin, in The Ant and the Peacock , displays a raw talent clearly equal (...) to that of our finest portraitists, but has placed herself into a position even worse than Mr. Lely's. Cromwell's painter at least faced the subject himself; Cronin has produced an uncritical gloss upon a false and simplistic view that never was more than a caricature of Darwinian theory. (shrink)
Understanding after the fact confers no special perspicacity. The real test for any diviner can only lie in grasping the outcome at the outset. Correct predictions, in themselves, offer no proof of true wisdom, for how can we distinguish dumb luck from horse sense? The only good experiment is, alas, the most undoable of all intriguing thoughts in a world of irrevocable history-to run back the tape and play it again, Sam.
ncongruous places often inspire anomalous stories. In early 1984, I spent several nights at the Vatican housed in a hotel built for itinerant priests. While pondering over such puzzling issues as the intended function of the bidets in each bathroom, and hungering for something other than plum jam on my breakfast rolls (why did the basket only contain hundreds of identical plum packets and not a one of, say, strawberry?), I encountered yet another among the innumerable issues of contrasting cultures (...) that can make life so interesting. Our crowd (present in Rome for a meeting on nuclear winter sponsored by the Pontifical Academy of Sciences) shared the hotel with a group of French and Italian Jesuit priests who were also professional scientists. (shrink)
¶1 Charles Darwin began the last paragraph of The Origin of Species (1859) with a famous metaphor about life's diversity and ecological complexity: It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent on each other in so complex a manner, have (...) all been produced by laws acting around us. He then begins the final sentence of the book with an equally famous statement: "There is grandeur in this view of life....". (shrink)
In 1979, Lewontin and I borrowed the archi- tectural term “spandrel” (using the pendentives of San Marco in Venice as an example) to designate the class of forms and spaces that arise as necessary byproducts of another decision in design, and not as adaptations for direct utility in them- selves. This proposal has generated a large literature featur- ing two critiques: (i) the terminological claim that the span- drels of San Marco are not true spandrels at all and (ii) the (...) conceptual claim that they are adaptations and not byprod- ucts. The features of the San Marco pendentives that we explicitly defined as spandrel-properties—their necessary number (four) and shape (roughly triangular)—are inevitable architectural byproducts, whatever the structural attributes of the pendentives themselves. The term spandrel may be extended from its particular architectural use for two- dimensional byproducts to the generality of “spaces left over,” a definition that properly includes the San Marco pendentives. Evolutionary biology needs such an explicit term for features arising as byproducts, rather than adaptations, whatever their subsequent exaptive utility. The concept of biological span- drels—including the examples here given of masculinized genitalia in female hyenas, exaptive use of an umbilicus as a brooding chamber by snails, the shoulder hump of the giant Irish deer, and several key features of human mentality— anchors the critique of overreliance upon adaptive scenarios in evolutionary explanation. Causes of historical origin must always be separated from current utilities; their conf lation has seriously hampered the evolutionary analysis of form in the history of life. (shrink)
Two major clarifications have greatly abetted the understanding and fruitful expansion of the theory of natural selection in recent years: the acknowledgment that interactors, not replicators, constitute the causal unit of selection; and the recognition that interactors are Darwinian individuals, and that such individuals exist with potency at several levels of organization (genes, organisms, demes, and species in particular), thus engendering a rich hierarchical theory of selection in contrast with Darwin’s own emphasis on the organismic level. But a piece of (...) the argument has been missing, and individuals at levels distinct from organisms have been denied potency (although granted existence within the undeniable logic of the theory), because they do not achieve individuality with the same devices used by organisms and therefore seem weak by comparison. We show here that different features define Darwinian individuality across scales of size and time. In particular, species-individuals may develop few emergent features as direct adaptations. The interactor approach works with emergent fitnesses, not with emergent features; and species, as a consequence of their different mechanism for achieving individuality (reproductive exclusivity among subparts, that is, among organisms), express many effects from other levels. Organisms, by contrast, suppress upwardly cascading effects, because the organismic style of individuality (by functional integration of subparts) does not permit much competition or differential reproduction of parts from within. Species do not suppress the operation of lower levels; such effects therefore become available as exaptations conferring emergent fitness—a primary source of the different strength that species achieve as effective Darwinian individuals in evolution. (shrink)
Uniformitarianism is a dual concept. Substantive uniformitarianism (a testable theory of geologic change postulating uniformity of rates or material conditions) is false and stifiqng to hypothesis formation. Methodological uniformitarianism (a procedural principle asserting spatial and temporal invariance of natural laws) belongs to the definition of science and is not unique to genic~~. Methodological uniformitarianism enabled Lyell to exclude the miraculous from geologic explanation; its invocation today is anachronistic since the question of divine intervention is no longer an issue in science. (...) Substantive uniformitarianism, an incorrect theory, should be abandoned. Methodological uniformitarianism, now a superfiuous term, is best confined to the past history of geology. (shrink)
IN LATE 1909, two great men corresponded across oceans, religions, generations, and races. Leo Tolstoy, sage of Christian nonviolence in his later years, wrote to the young Mohandas Gandhi, struggling for the rights of Indian settlers in South Africa.
Alexander wept at the height of his triumphs because he had no new worlds to conquer. Whitehead declared that all of philosophy had been a footnote to Plato. The Preacher exclaimed (Ecclesiastes 1:10): "Is there any thing whereof it may be said, See, this is new? It hath been already of old time, which was..
Gallileo described the universe in his most famous line: "This grand book is written in the language of mathematics, and its characters are triangles, circles, and other geometrical figures." Why should the laws of nature be subject to statement in such elegantly basic algebra? Why does gravity work by the principle of inverse squares? Why do simple geometrics pervade nature--from the hexagons of the honeycomb, to the complex architecture of crystals? D'Arcy Thompson, author of Growth and Form and my earliest (...) intellectual hero (along with my father and Charles Darwin), wrote that "the harmony of the world is made manifest in Form and Number, and the heart and soul and all the poetry of Natural Philosophy are embodied in the concept of math ematical beauty." Many scientists, if only to coin a striking metaphor, depict a creating God as a mathematician from the realm of Plato or Pythagoras. The physicist James Jeans wrote: "From the intrinsic evidence of his creation, the Great Architect of the Universe now begins to appear as a pure mathematician.". (shrink)
irtley Mather, who died last year at age ninety, was a pillar of both science and Christian religion in America and one of my dearest friends. The difference of a half-century in our ages evaporated before our common interests. The most curious thing we shared was a battle we each fought at the same age. For Kirtley had gone to Tennessee with Clarence Darrow to testify for evolution at the Scopes trial of 1925. When I think that we are enmeshed (...) again in the same struggle for one of the best documented, most compelling and exciting concepts in all of science, I don't know whether to laugh or cry. (shrink)
n one of the numerous movie versions of A Christmas Carol , Ebenezer Scrooge, mounting the steps to visit his dying partner, Jacob Marley, encounters a dignified gentleman sitting on a landing. "Are you the doctor?" Scrooge inquires. "No," replies the man, "I'm the undertaker; ours is a very competitive business." The cutthrought world of intellectuals must rank a close second, and few events attract more notice than a proclamation that popular ideas have died. Darwin's theory of natural selection has (...) been a perennial candidate for burial. (shrink)
Big Brother, the tyrant of George Orwell's 1984, directed his daily Two Minutes Hate against Emmanuel Goldstein, enemy of the people. When I studied evolutionary biology in graduate school during the mid-1960s, official rebuke and derision focused upon Richard Goldschmidt, a famous geneticist who, we were told, had gone astray. Although 1984 creeps up on us, I trust that the world will not be in Big Brother's grip by then. I do, however, predict that during this decade Goldschmidt will be (...) largely vindicated in the world of evolutionary biology. (shrink)
teach a course at Harvard with philosopher Robert Nozick and lawyer Alan Dershowitz. We take major issues engaged by each of our professions—from abortion to racism to right-to-die—and we try to explore and integrate our various approaches. We raise many questions and reach no solutions.
provides a superb and unusual opportunity to gain insight into the meaning of experiment as a method in science. The primary desideratum in all experiments is reduction of confusing variables: we bring all the buzzing and blooming confusion of the external world into our laboratories and, holding all else constant in our artificial simplicity, try to vary just one potential factor at a time. But many subject defy the use of such an experimental method—particularly most social phenomena—because importation into the (...) laboratory destroys the subject of the investigation, and then we must yearn for simplifying guides in nature. If the external world occasionally obliges by holding some crucial factors constant for us, we can only offer thanks for this natural boost to understanding. (shrink)
hen the Right Honorable and Reverend Francis Henry, earl of Bridgewater, died in February, 1829, he left £8,000 to support a series of books "on the power, wisdom and goodness of God, as manifested in the creation." William Buckland, England's first official academic geologist and later dean of Westminster, was invited to compose one of the nine Bridgewater Treatises. In it he discussed the most pressing problem of natural theology: if God is benevolent and the creation displays his "power, wisdom (...) and goodness," then why are we surrounded with pain, suffering, and apparently senseless cruelty in the animal world? (shrink)
IN THE PRELUDE to Middlemarch, George Eliot lamented the unfulfilled lives of talented women: Some have felt that these blundering lives are due to the inconvenient indefiniteness with which the Supreme Power has fashioned the natures of women: if there were one level of feminine incompetence as strict as the ability to count three and no more, the social lot of women might be treated with scientific certitude. Eliot goes on to discount the idea of innate limitation, but while she (...) wrote in 1872, the leaders of European anthropometry were trying to measure "with scientific certitude" the inferiority of women. Anthropometry, or measurement of the human body, is not so fashionable a field these days, but it dominated the human sciences for much of the nineteenth century and remained popular until intelligence testing replaced skull measurement as a favored device for making invidious comparisons among races, classes, and sexes. Craniometry, or measurement of the skull, commanded the most attention and respect. Its unquestioned leader, Paul Broca (1824-80), professor of clinical surgery at the Faculty of Medicine in Paris, gathered a school of disciples and imitators around himself. Their work, so meticulous and apparently irrefutable, exerted great influence and won high esteem as a jewel of nineteenth-century science. Broca's work seemed particularly invulnerable to refutation. Had he not measured with the most scrupulous care and accuracy? (Indeed, he had. I have the greatest respect for Broca's meticulous procedure. His numbers are sound. But science is an inferential exercise, not a catalog of facts. Numbers, by themselves, specify nothing. All depends upon what you do with them.) Broca depicted himself as an apostle of objectivity, a man who bowed before facts and cast aside superstition and sentimentality. He declared that "there is no faith, however respectable, no interest, however legitimate, which must not accommodate itself to the progress of human knowledge and bend before truth." Women, like it or not, had smaller brains than men and, therefore, could not equal them in intelligence.. (shrink)
The world, unfortunately, rarely matches our hopes and consistently refuses to behave in a reasonable manner. The psalmist did not distinguish himself as an acute observer when he wrote: "I have been young, and now am old; yet have I not seen the righteous forsaken, nor his seed begging bread." The tyranny of what seems reasonable often impedes science. Who before Einstein would have believed that the mass and aging of an object could be affected by its velocity near the (...) speed of light? (shrink)
An 'anatomy' is a literary work that treats a particul.1r topic at great length and in minute detail. Viewed as a contribution to that genre, this massive and prolix tome may be read with patience and also with sympathy for its author. Gould diccl around the time that it was published, and the book is a fitting monument to his life's work. Because he goes into so much detail, providing an immense amount..
rom Flesh Gordon to Alex in Wonderland , title parodies have been a stock-in-trade of low comedy. We may not anticipate a tactical similarity between the mayhem of Mad magazine's movie reviews and the titles of major scientific works, yet two important nineteenth-century critiques of Darwin parodied his most famous phrases in their headings.
In his great aria "La calumnia," Don Basillo, the music master of Rossini's Barber of Seville, graphically describes how evil whispers grow, with appropriate watering, into truly grand and injurious calumnies. For the less conniving among us, the same lesson may be read with opposite intent: in adversity, try to contain. The desire to pin evil deeds upon a single soul acting alone reflects this strategy; conspiracy theories have a terrible tendency to ramify like Basillo's whispers until the runaway solution (...) to "whodunit" becomes "everybodydunit." But conspiracies do occur. Even the pros and pols now doubt that Lee Harvey Oswald  acted alone; and everybody did do it on the Orient Express. 2.. (shrink)
he landscape of every career contains a few crevasses, and usually a more extensive valley or two—for every Ruth's bat a Buckner's legs; for every lopsided victory at Agincourt, a bloodbath at Antietam. Darwin's Origin of Species contains some wonderful insights and magnificent lines, but this masterpiece also includes a few notable clunkers. Darwin experienced most embarrassment from the following passage, curtailed and largely expunged from later editions of his book: In North America the black bear was seen by Hearne (...) swimming for hours with widely open mouth, thus catching, like a whale, insects in the water. Even in so extreme a case as this, if the supply of insects were constant, and if better adapted competitors did not already exist in the country, I can see no difficulty in a race of bears being rendered, by natural selection, more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale. Why did Darwin become so chagrined about this passage? His hypothetical tale may be pure speculation and conjecture, but the scenario is not entirely absurd. Darwin's discomfort arose, I think, from his failure to follow a scientific norm of a more sociocultural nature. Scientific conclusions supposedly rest upon facts and information. Speculation is not entirely taboo, and may sometimes be necessary faute de mieux. But when scientists propose truly novel and comprehensive theories—as Darwin tried to do in advancing natural selection as the primary mechanism of evolution—they need particularly good support, and invented hypothetical cases just don't supply sufficient confidence for crucial conclusions. (shrink)
ig Brother, the tyrant of George Orwell's 1984, directed his daily Two Minutes Hate against Emmanuel Goldstein, enemy of the people. When I studied evolutionary biology in graduate school during the mid 1960s, official rebuke and derision focused upon Richard Goldschmidt , a famous geneticist who, we were told, had gone astray. Although 1984 creeps up on us, I trust that the world will not be in Big Brother's grip by then. I do, however, predict that during this decade Goldschmidt (...) will be largely vindicated in the world of evolutionary biology. (shrink)
From the moment of discovery, the Piltdown "fossils" were the center of controversy. Piltdown apparently provided a human fossil on English soil, a maker for the eoliths, and proof that the brain came first in human evolution and that an anatomically modern braincase was present at the beginning of the Ice Age. Every conclusion was important and controversial, and for many years it was not possible to discuss human evolution without considering Piltdown. Hundreds of papers were written about the discoveries, (...) but the problem remained. Anatomically it seemed impossible to associate the skull and jaw, but the chance association of an ape's jaw and a human skull in England seemed at least as improbable. The solution came when J.S. Weiner, Kenneth Oakley, and W.L. le Cros Clark showed that everything was fake–the bones had been stained, ape's teeth filed down, and fossils added to the assemblage to determine the antiquity. The whole matter is carefully reviewed in Weiner's The Piltdown Forgery ( 1955). (shrink)
For principled and substantially philosophical reasons, based largely on his reform of natural history by inverting the Paleyan notion of overarching and purposeful bene¢cence in the construction of organisms, Darwin built his theory of selection at the single causal level of individual bodies engaged in unconscious (and metaphorical) struggle for their own reproductive success. But the central logic of the theory allows selection to work e¡ectively on entities at several levels of a genealogical hierarchy, provided that they embody a set (...) of requisite features for de¢ning evolutionary individuality. Genes, cell lineages, demes, species, and cladesöas well as Darwin's favoured organismsöembody these requisite features in enough cases to form important levels of selection in the history of life. (shrink)
Two groups of researchers released the formal report of data for the human genome last Monday -- on the birthday of Charles Darwin, who jump-started our biological understanding of life's nature and evolution when he published ''The Origin of Species'' in 1859. On Tuesday, and for only the second time in 35 years of teaching, I dropped my intended schedule -- to discuss the importance of this work with my undergraduate course on the history of life. (The only other case, (...) in a distant age of the late 60's, fell a half-hour after radical students had seized University Hall and physically ejected the deans; this time at least, I told my students, the reason for the change lay squarely within the subject matter of the course!). (shrink)
n my adopted home of Puritan New England, I have learned that personal indulgence is a vice to be tolerated only at rare intervals. Combine this stricture with two further principles and this essay achieves its rationale: first, that we celebrate in hundreds and their easy multiples (the Columbian quincentenary and the fiftieth anniversary of DiMaggio's hitting streak—both about equally important, and only the latter an unambiguous good); second, that geologists learn to take the long view.
Thomas Henry Huxley designated three men as the finest intellects of 19th century natural history: his dear friend Charles Darwin; his most worthy opponent Georges Cuvier; and Karl Ernst von Baer, who discovered the mammalian egg cell in 1827 and wrote the founding treatise of modern embryology in 1828. Of these three, posterity has largely forgotten von Baer, who suffered a severe mental breakdown in the 1830's, but then recovered and moved to Russia (not uncommon for a German-speaking Estonian national), (...) where he enjoyed a distinguished second university career, largely in anthropology and lasting well into the 1870's. (shrink)
y interest in paleontology began in a childhood fascination with dinosaurs. I spent a substantial part of my youth reading the modest literature then available for children on the history of life. I well remember the invariant scheme used to divide the fossil record into a series of "ages" representing the progress that supposedly marked the march of evolution: the "Age of Invertebrates," followed by the Age of Fishes, Reptiles, Mammals and, finally, with all the parochiality of the engendered language (...) then current, the "Age of Man.". (shrink)
Flesh of My Flesh is a collection of articles by today's most respected scientists, philosophers, bioethicists, theologians, and law professors about whether we should allow human cloning. It includes historical pieces to provide background for the current debate. Religious, philosophical, and legal points of view are all represented.