Darwin's Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design

by Stephen C. Meyer

Sedgwick emphasized that these Cambrian animal fossils appeared to pop out of nowhere into the geological column. But he also stressed what he viewed as a broader reason to doubt Darwin’s evolutionary model: the sudden appearance of the Cambrian animals was merely the most outstanding instance of a pattern of discontinuity that extends throughout the geologic column. Where in the Ordovician strata, for instance, are many of the families of the trilobites and brachiopods present in the Cambrian just below it?15 These creatures along with numerous other types suddenly disappear. But just as suddenly one finds newcomers in the Ordovician strata like the eurypterans (sea scorpions), starfish, and tetracorals (see Fig. 1.5).16 In a later Paleozoic period called the Devonian, the first amphibians (e.g., Ichthyostega) arise. Much later, many staples of the Paleozoic era (which encompasses the Cambrian, Ordovician, and four subsequent periods) suddenly go extinct in a period called the Permian.17 Then, in the Triassic period that follows, completely novel animals such as turtles and dinosaurs emerge.18 Such discontinuity, Sedgwick argued, is not the exception, but the rule.

“The abrupt manner in which whole groups of species suddenly appear in certain formations has been urged by several paleontologists—for instance, by Agassiz, Pictet, and Sedgwick—as a fatal objection to the belief in the transmutation of species. If numerous species, belonging to the same genera or families, have really started into life all at once, the fact would be fatal to the theory of descent with slow modification through natural selection.”

Plate tectonic activity explains why a trove of sea creatures were found fossilized in the mountains of Yoho National Park rather than along a seafloor somewhere.

If we don’t have fossils documenting a common animal ancestor, and if genetic studies produce such different and contradictory divergence times, how do we know what the tree of life should look like and when the first animals began to diverge from a common ancestor?

My point in summarizing these disputes is simply to note that the molecular and anatomical data commonly disagree, that one can find partisans on every side, that the debate is persistent and ongoing, and that, therefore, the statements of Dawkins, Coyne, and many others about all the evidence (molecular and anatomical) supporting a single, unambiguous animal tree are manifestly false. As can readily be seen by comparing Figures 6.1a and 6.1b,36 these hypotheses—Coelomata and Ecdysozoa—contradict each other. Although both might be false, both cannot be true.

Many critics of punctuated equilibrium have noted this problem. As Richard Dawkins wrote in 1986: “What I mainly want a theory of evolution to do is explain complex, well-designed mechanisms like hearts, hands, eyes and echolocation. Nobody, not even the most ardent species selectionist, thinks that species selection can do this.”31 Or as paleontologist Jeffrey Levinton argued in 1988, “It is inconceivable how selection among species can produce the evolution of detailed morphological structures. . . . Species selection did not form an eye.”32

After the 1975 Steven Spielberg film Jaws became a big hit, one small-town motel advertised “Shark-Free Pool.” Proponents of the second evolutionary scenario (gene duplication, followed by neutral evolution), envision an evolutionary pool where there are no consequences for mutational missteps—by analogy, a pool with no predators. But to extend the illustration, picture a predator-free pool the size of our galaxy. Now picture a blindfolded man dropped into the middle of it. He must swim to the far side, to the one spot on the edge of the pool where a ladder would give him a way out. He’s safe from predators, but it will do him no good. He needs direction, some way of gauging his progress, and an immense amount of time. But he has none of these and so he will arrive at the ladder in neither a hundred years, nor a hundred billion. Similarly, in the classical model of gene evolution, random mutations must thrash about aimlessly in immense combinatorial space, a space that could not be explored by this means in the entire history of life on earth, let alone in the few million years of the Cambrian explosion.

Richard Dawkins has noted that scientific theories can rely on only so much “luck” before they cease to be credible.

In his book The Edge of Evolution, Michael Behe illustrates these principles using a charming analogy to the Powerball lottery game that many American state governments use to raise money. To win at Powerball, contestants must purchase tickets with six numbers that match the numbers printed on six balls drawn from two drums. Five of the balls are selected from a drum containing 59 white balls, numbered 1 through 59. A sixth red ball, the so-called power ball, is chosen out of a drum of 35 red balls numbered 1 to 35. To win the jackpot—which can exceed $100 million—a player must purchase a ticket listing all six of the chosen numbers in any order. The Powerball website lists the probability of matching all six balls at roughly 1 in 175 million. Depending on how many tickets have been purchased and how frequently drawings occur, it may take a very long time for someone to win. Behe asked his readers first to consider how long it will take, on average, to generate a lottery ticket with the winning numbers. He notes that knowing the probability of drawing such a winning ticket isn’t sufficient. The calculation also requires knowing how often drawings occur and how many tickets are sold. As Behe explains: “If the odds of winning are one in a hundred million, and if a million people play every time, then it will take on average about a hundred drawings for someone to win.” If there are about a hundred drawings per year, with a million people playing per drawing, “then it would t...

to the extent that cell structures can be altered, these alterations are overwhelmingly likely to have harmful or catastrophic consequences. The original Spemann and Mangold experiment did, of course, involve forcibly altering an important repository of epigenetic information in a developing embryo. Yet the resulting embryo, though interesting and illustrative of the importance of epigenetic information, did not stand a chance of surviving in the wild, let alone reproducing.

The question of whether a theory is “scientific” is really a red herring. What we really want to know is whether a theory is true or false, supported by the evidence or not, worthy of our belief or not. And we cannot decide those questions by applying a set of abstract criteria that purport to tell in advance what all good scientific theories must look like.