Evolutionary Concepts & Transitions Through Time
by Robert A. Martin, Murray State University
A couple of weeks ago I lectured at Murray State University, in Murray, Kentucky, a lovely college town in the western part of the state, itself a couple of notches from the buckle of the Bible Belt. While there I met Robert A. Martin, a paleontologist who gave me a copy of his new book, Missing Links: Evolutionary Concepts and Transitions Through Time (Jones & Bartlett, 2004, ISBN 0763721964). It is a wonderfully compact answer to creationists’ demand to “show me just one transitional fossil.” Well, here are 300 pages of them! Check it out. — Michael Shermer
Missing Links provides readers with a compendium of scientific evidence of extinct organisms, or “missing links,” that bridge the evolutionary gaps between primordial species and modern life. The book introduces newcomers to the field of evolutionary science with an accessible discussion of basic scientific practices, rock and fossil dating techniques, and schools of classification. Readers are then ushered through a fascinating array of examples of evolutionary transition at all chronological and geographical scales, from the ultimate origins of life on Earth to the morphological changes that readers will observe during their lifetimes.
Offering a lucid primer on evolutionary science, as well as a series of case studies and fossil histories in support of evolutionary theory, Missing Links serves as an ideal short introduction to evolution for students and general readers.
Section I: A Primer of Evolutionary Science
Section II: Case Histories
Epilogue: Charles Darwin and the Fossil “Problem”
about the author
Robert A. Martin is a Professor in the Department of Biological Sciences, Murray State University. He holds a Ph.D. in Zoology at the University of Florida. Dr. Martin has published more than 50 professional articles in the areas of mammalian evolution and paleoecology and currently conducts fieldwork on Late Cenozoic small mammal associations in Kansas and southern Spain. His work has been recently supported by the National Geographic Society and the National Science Foundation.
The following is Paul R. Gross’ review of Why Intelligent Design Fails: A Scientific Critique of the New Creationism (Mark Young and Taner Edis, eds.) (Rutgers, 2004, ISBN 081353433X).
Dr. Paul R. Gross is University Professor of Life Sciences, emeritus, at the University of Virginia. His baccalaureate and doctoral degrees are from the University of Pennsylvania. He is a developmental and molecular biologist who has taught at Brown, Rochester, MIT, and the University of Virginia. He is co-author with Norman Levitt of Higher Superstition (Johns Hopkins University Press, 1994), and with Barbara Forrest of Creationism’s Trojan Horse: The Wedge of Intelligent Design (Oxford University Press, 2003).
Patience and Absurdity:
How to Deal with Intelligent Design Creationism
a book review by Paul R. Gross
Physicists Matt Young and Taner Edis are the editors of a new volume whose contributors are working scholars in the sciences touched by the newest expression of “creation science”: Intelligent Design (ID) Theory. Why Intelligent Design Fails is a patient assessment of all the scientific claims made in connection with ID. The half dozen science-enabled spokesmen for ID are the indispensable core group of an international neo-creationist big tent. Goals of the American movement are sweeping: they begin with a highly visible, well-funded, nationwide effort to demean evolutionary science in American school (K-12) curricula. ID is offered as a better alternative. The hoped-for result is the addition of ID to, or even its substitution for, the teaching of evolution. Which would mean substituting early 19 th-century nature study for modern biology. The admitted ultimate goal of the ID movement is to topple natural science (they berate it as “materialism”) from its pedestal in Western culture and to replace it with “theistic science.”
For several decades, similarly imperialistic goals of a coterie of cultural theorists have been achieved in many university departments of social sciences and humanities, including art history. One well-known art critic, Roger Kimball, has long been an analyst of their postmodern, postcolonial, gender-feminist chic. But now he admits to second thoughts about the value of patient analysis of its gaucheries. Painstaking analysis, applied to presentist posturing like that which now passes in some parts of the academy for art history, can be counterproductive. He worries, in a new book, that careful analysis of wishful absurdities can suggest, to onlookers innocent of academic high culture, that the absurdities are legitimate alternatives to the serious study of art—that the conflict is between equally meritorious interpretations. “Patient objections to the ludicrous,” he writes, “become ludicrous themselves.”
But this is a worry that goes beyond cultural studies, and it has now become acute in the evolutionary sciences. Patient analysis of creationist blunders and sham reasoning (definition: ostensible inquiry whose conclusion is fixed in advance) has as often done harm as good to the life sciences. Biologists are confronted endlessly with touring companies of debaters and religious charismatics who present the scripts of “scientific” creationism. Most evolutionists and other biologists who are aware of these performances take the easy way out: they ignore all religion-based commentary on science, justifying indifference by declaring that to argue would dignify absurdity. Or worse: they shrug off sham reasoning with a glib dismissal: “Nobody really believes that stuff.” The excuse is itself absurd: Vast numbers—indeed, a majority—of our countrymen do believe that stuff, even as they are ignorant of the real science.
Still, refusal to dignify absurdity has some merit. The creationist position, especially this newest form of it, is pure Hollywood: There is No Such Thing As Bad Publicity. That this view is held by the ID leadership is fully documented in several recent studies of the movement. Thus, almost any careful examination of ID by qualified scientists, mathematicians, and philosophers—especially by those with strong credentials in evolution or cosmology—is likely to be advertised by ID publicists as proof of the scientific importance of ID. Any non-polemical response to it is described to the mass audience for anti-evolution as showing the revolutionary truth of ID, the fear and trembling it causes among Darwinists. That a few dedicated scientists take the trouble to answer ID “theory” in detail is regularly adduced—in ID books, editorials, opinion columns, talk shows, dedicated internet sites, and in a growing numbers of activist student organizations around the country—as signaling the collapse of Darwinism.
The contributors to Why Intelligent Design Fails (WIDF) have risked being so used. But they decided, evidently, to accept this risk. They decided to examine every supposedly scientific (or mathematical, or epistemological) claim of ID, patiently, in detail, and to offer only those conclusions about the value of ID science—if any—that emerge clearly in the individual critiques and from their totality. Whether this risk was justified will be known only if and when the book is widely read, and then responded to (as inevitably it will be) at those many creationist web sites, meetings, talk shows, conferences, and clubs. If they do no more than to denounce the book and disparage its authors (as they began to do the day it was listed on Amazon.com), WIDF will have succeeded. If instead they proclaim it evidence for the scientific muscle of ID theory, the tables will, at least to some extent, have been turned. But about the quality of the critiques in this book, and of the totality, there is no doubt. This is honest, technically competent—patient—inquiry; the critique of the newest form of creation science is devastating.
The Science of ID “Science”
Those scare-quotes on “science” are in ironic honor of recent and current philosophers and sociologists of science who use them routinely to sabotage the value of any word they surround. Thus if you are a relativist, you write about “truth” to signal your discovery that there is no such thing. If you are convinced that objectivity is made impossible by an observer’s culture or ethnicity, then you write “objectivity.” WIDF is about the scientific claims of ID, not about its background, history, purposes, politics, and practices. All those are covered in other books and merely touched upon in the short introduction. The undertaking here is, rather, to examine and judge only those ID claims that have some original scientific (or mathematical) content. Therefore the book lacks any discussion of, for example, one of the iconic books of the movement, Jonathan Wells’s Icons of Evolution, which offers no science of its own but rather a litany of accusations against evolutionary biology, mined from the literature of creationism and applied to quotes dug up from internal arguments in the biological literature. Its burden is that evolution as taught is wrong or fraudulent, and must therefore not be presented to children without the strongest disclaimers. Wisely, the contributors to WIDF have ignored all this. It has already been dismantled, point by point and claim by claim, in lengthy treatments by scientists who are experts in all the fields involved. A check at www.ncseweb.org will unearth them all. There are, on the other hand, purportedly new arguments for ID: and those are the mainstay of its nationwide campaign. They fall loosely into three classes:
The featured argument was offered by biochemist Michael Behe, who proposed in 1996 that at the sub-cellular level of molecular machines and chemical reaction pathways, important systems are “irreducibly complex” (IC). Such systems have multiple working parts, each of which is essential for function. Absence of any part would destroy the function. But, his argument goes, non-functioning systems are not subject to positive natural selection. Therefore complex functioning systems cannot have evolved gradually by any Darwinian mechanism, which requires that all intermediate stages have some function. They must have arisen in one fell swoop. Therefore (sic) they are the product of some designing agency—of intelligent design. All recent ID biological claims relate to this one, and the most widely exposed mathematical claim depends upon it too. A body of other, very old but regularly updated creationist claims comes along with ID, however. These are all versions of the young-earth creationist preoccupation: that while there may be some common descent at a very low level (contemporary species, perhaps, from the original basic kinds), the world’s biota are the products of God’s “kinds,” as per Genesis or in separate interventions.
These arguments challenge the logic or the formal plausibility of prevailing scientific accounts of universal origins and of the history of life on Earth. There are several threads of which these arguments are woven, some very old, some relatively new. The oldest are creationist canards from thermodynamics, for example: that since the entropy of a (closed!) system either rises or remains constant, and its degree of order (complexity) must therefore remain constant or fall, the spontaneous (read “natural”) appearance of life-forms (which means increased order and complexity) is impossible. Something other than nature alone must have done it. Another class of arguments depends upon heuristic models—Michael Behe’s mousetrap, for example—as illustrations of irreducible complexity or the need for a purposeful designer. The more sophisticated arguments surfacing in ID ignore these old thermodynamics howlers and focus, instead, on supposed limitations of self-organizing processes or on the several anthropic principles (“the fine-tuning of the universe for life”) as indicators of supra-physical design in the universe.
These are descendants of the primitive creationist claim of life’s improbability, as calculated. If, that is, the assembly of something necessary to life requires a coming together, at just the right time and place, of a large number of individual events or objects, each of which has its own (often low) probability, then the probability of the assembly occurring by chance is the product of all those constituent probabilities. If that product is small enough, then the likelihood of the assembly happening in any real time-interval is effectively zero. Again, the more sophisticated ID proponents shun this argument, steering away from the self-evident absurdity of such clearly inapplicable models. Nevertheless, the flawed basis in equi-probability and multiplication remains in the fancier versions. The achievement of William Dembski, the movement’s mathematician-theologian-philosopher, is to couple such arguments with a purely deductive device, an eliminative “design inference,” by which—he claims (but has never demonstrated)—the presence of design can be discovered as the cause of any supposedly natural process. This is to be done by considering the probabilities of chance and “regularity” (physical law) as causes, and then by the extent to which the still unexplained event or object has “specified complexity.”
Judging ID Science
WIDF analyses of these ID offerings are provided by a team of well-qualified contributors. For the biological claims, there are chapters from paleontologist Alan Gishlick, biologist-engineer Gert Korthof, molecular pharmacologist Ian Musgrave, and molecular biologist David Ussery. For logic, epistemology, physics, and cosmology, there are contributions from physicist (and editor) Taner Edis, taphonomist (the study of fossilization) Gary Hurd, bio-mathematician Istvan Karsai, physicist-engineer Mark Perakh, philosopher-biologist Niall Shanks, physicist Victor Stenger, and physicist (editor) Matt Young. Finally, the mathematical and probabilistic arguments are examined closely by zoologist-computer scientist Wesley Elsberry, physicist Mark Perakh, and mathematician-computer scientist Jeffrey Shallit.
Result? Not one of the ID claims is sustained, let alone proven, in the massive output of ID to date. Most of the claims are shown to be simply bad science. The expository style of WIDF is for the most part respectful of the authors and claims analyzed. It is therefore very remarkable that those presumably qualified ID authors should have committed themselves, and to some extent their academic careers, to a relentless, public elaboration of soft claims, bad arguments, and plain mistakes. One can only guess that they are driven by motivation and sincere feelings other than simple dedication to doing the best possible science.
A few examples, telegraphically stated, must suffice here. Irreducible complexity will do for most of the biology. Behe’s entire argument depends upon the implied necessity that every piece of a sub-cellular molecular machine—and most such “pieces” are proteins, which are encoded in genes—be provided for ab initio. That is, it requires that all the proteins of a supposedly irreducibly complex system are (or were) provided from the beginning, or that the genes for them were already there at the beginning but not necessarily being used. Examples he adduces of such systems are the blood clotting cascade and the bacterial flagellum, which functions as an outboard motor for the bacterial cell. But as the biologist-authors of WIDF show, there is no need for all the parts of any such system to be there, or to have been there as such, from the beginning. Behe made a simple, but bad, mistake. He overlooked gene duplication and the independent evolution of copies; and he forgot that many, perhaps most, proteins have multiple functions. He seems not to have thought through the startling redundancy of subcellular functions. Thus, in separate WIDF chapters, Ussery and Musgrave present unshakable evidence that systems Behe would consider IC have evolved by “Darwinian mechanisms”; and that relic intermediates for many of the steps in that evolution survive as the current, simpler version of the system in some contemporary organism.
Gishlick, in an unexpected way, tops even those no-nonsense contributions. Taking the definition of IC at face value, he shows that there must be IC systems at the level of anatomy, as well as of biochemistry. One well-studied IC system of contemporary animal anatomy is the flight machine of birds: the wing. Gishlick sets out the special parts of the working wing and all its auxiliaries, from wrist bones to special, airfoil-producing flight feathers. He then shows that all those parts appeared during the long course of Avian evolution over geologic time, and that for most of that long stretch, those parts functioned usefully (therefore selectably) for something other than flight. Evolution of functional systems is almost always a story of co-optation, as evolutionists have known for nearly a century. Gishlick’s naming of known fossil species that had those intermediate states of the system as it evolved, is an overwhelming dismissal of the central claim from IC.
Gert Korthof undertakes the modest job of examining descent with modification as viewed by the ID leaders. “Descent with modification” was Darwin’s own shorthand for the history of life on Earth, for the facts of evolution as he gathered them together (even in the absence of a workable idea about heredity). All the ID leaders equivocate about this. They do hesitate to state, if not to imply, the young-earth creationist absurdity that all species are “kinds,” and that all kinds were called into being by God. Biologist Behe, for example, concedes that descent with modification has occurred; but he indicates that it can’t account for IC, so that intelligent design must be at the heart of real species-formation—if and when that happens. Others among the ID leadership either deny any taxonomically significant descent with modification, or labor to create complex “alternate” taxonomies that allow species to proliferate, but only as products of basic families—the “kinds” of genesis. Korthof’s essay is a compact gem: he shows that none of these jury-rigged schemes can possibly explain the huge matrix of facts out of which modern evolutionary biology grows, and that they are severally illogical to boot.
The part-epistemological, part-faux-thermodynamic ID claims to the effect that information-rich complexity cannot arise spontaneously in natural systems are addressed by several of these authors. But Shanks and Karsai describe such spontaneous complexities as the beautiful Benard (convection) cells that organize themselves in an asymmetrically-heated Petri dish, and the astonishing, ad hoc shaping of cellular structure in wasp nests, whose builders have no intelligent-design contingency book for nest structure. The last resort of ID proponents when defeated, as they have been in arguments about the need for designer-intervention in such historical processes as evolution and such contemporary processes as these discussed by Shanks and Karsai, is to invoke the strong anthropic principle. The universe is exquisitely fine-tuned, this says, as regards the values of its fundamental physical constants and the possible structures arising because of them—fine-tuned for “life as we know it,” for us. Therefore the universe must have been pre-loaded with the right information—the “complex specified information” that William Dembski and Behe and the others argue is the unfailing diagnostic of an intelligent designer. Victor Stenger, however, explains here why current theoretical and astro- physics, especially multiple-universes cosmological theory, is perfectly at home with a “fine-tuned” universe inhabited by ourselves, and with its having arisen spontaneously.
Mark Perakh has taken great pains to study and analyze the claims of Dembski’s most influential theoretical book so far. That book presents an argument based upon certain induction-formalizing, optimizing theorems discovered by mathematicians David Wolpert and William MacReady in 1997. As Dembski exploits them, these so-called “No Free Lunch” theorems mean that the “the Darwinian mechanism,” taken to mean iterated algorithmic searches on a (biological) fitness landscape, cannot in general find the kinds of solution represented in the complexity of biological organisms—unless necessary information is incorporated beforehand in the algorithm itself. “Front-loading” again. But Perakh’s study shows that this conclusion results from a misunderstanding and misapplication of the No Free Lunch theorems. David Wolpert, co-discoverer of the theorems, dismissed Dembski’s prolix argument as “written in Jello.” Elsberry and Shallit, finally, provide a well-named essay, “Playing Games with Probability: Dembski’s Complex Specified Information.” In it they show that this most fundamental (and most obscure) of the formal elements of Intelligent Design Theory is simply incoherent.
The editors, Young and Edis, contribute strong chapters of their own on a number of these points and also provide concise but useful background on the ID movement, on the epistemological issues, and on ID congeners elsewhere in the religious world (for example in Islam). Gary Hurd provides a very useful appendix on organizations and websites concerned with ID (pro and con).
What’s Really Happening
Much of this might appear to professional biologists to be nit-picking; and in a sense it is. But it is nit-picking because the claims of neo-creationism are mostly nits. They are quote-minings, trivially literal models such as mousetraps and painted bulls-eyes, or obscure mathematical-probabilistic arguments based upon unrealistic models of biological phenomena. Biologists who know what has been going on in evolutionary science the past decade or two can be, understandably, bemused. They know that there has been an explosion of progress in study of the central process of evolution: the formation of new species—speciation. They are aware of excellent recent books, popular and professional, recounting that progress, conveying what we know today of at least some of the real mechanisms by which speciation has occurred in the past and is happening all around us, now.
They recognize that providing a fully detailed account of macroevolution is the daunting task yet before us, but that the fruitful marriage of molecular genetics and developmental evolutionary biology has already provided plausible answers to the basic question: how the proliferation of animal body plans happened, at least since they first fossilized well during the lower Cambrian. The forms demonstrated then heralded the eventual diversity. Evolutionists know now that the Cambrian “explosion” was not a literal explosion: that the rapid unfolding of body-plans in the lower Cambrian was inherited from ancestors: and some of those ancestors have been found. An ancestral Echinoderm (not yet an Echinoderm) has at last been discovered in the Chengjiang deposits of China. The Echinoderms did not appear explosively, by some act of special creation. They evolved. There is no reason to doubt that the same was true for the other phyla. One of the elusive, predicted, and long-awaited microscopic ancestors of all bilaterian animals has been found, fossilized, in the Doushanto formation in China. It dates to some 50 million years before the Cambrian.
Every reasonably informed biologist knows that there are big problems in the history of life on Earth still to be solved, and the ways to their solutions are not transparently clear. But that is the way of all science; and so far, natural science has delivered testable and daily-confirmed explanations. No other “science,” theistic or otherwise, has. Every one of those informed and open-minded biologists therefore knows, as well as anything about the physical world can be known, that organic evolution happened on this planet. And he or she knows that current evolutionary theory, the product of 145 years of often besieged work, of testing and winnowing, is one of our surest scientific possessions.
So it seems a trouble for busy scientists to give their time to truth-squads, examining (scrupulously, as do the WIDF contributors) the incessant nay-saying of creationists, and now of creationists who use the language of science and mathematics comfortably. But it must be done. There will be more anti-evolution, religiously motivated nay-saying, and there must be more books like WIDF. The stakes are high. Nothing less hangs in the balance than the hope that some fraction of the next generation—of our children—will get serious education in science, and that they will be capable of speaking truth not only to power, but to and for all their peers.
References & Notes
- Roger Kimball, The Rape of the Masters: How Political Correctness Sabotages Art. (San Francisco: Encounter Books, 2004), 52.
- Menno Schilthuizen, Frogs, Flies, and Dandelions: The Making of Species (Oxford: Oxford University Press, 2001).
- Jerry A. Coyne and H. Allen Orr, Speciation (Sunderland, MA: Sinauer Associates, Inc., 2004).