Probably no one has done more to popularize the argument for Intelligent Design (ID) in recent years than Stephen Meyer. In his books, Signature in the Cell: DNA and the Evidence for Intelligent Design and Darwin’s Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design, Meyer has given what I think is the strongest argument for ID to be found anywhere. Both of these books are clearly written and nicely illustrated. I believe readers will come away with a thorough understanding of Meyer’s views.
As a Christian, I’m convinced that the universe is a creation of God and, hence, designed. Indeed, the universe appears finely tuned as a life affirming creation. So Meyer and I share a lot in common on these points. As a philosopher and historian of science, I’m also very interested in everything science, particularly intersections between evolutionary biology, philosophy, and theology. Therefore, I was very interested in reading Darwin’s Doubt.
Meyer’s latest book takes its point of departure from what’s often called the Cambrian explosion. This is the “rapid” diversification and proliferation of the major animal body plans taking place in the Ediacaran and Cambrian periods (following Meyer, I will refer to these periods together as “the Cambrian”). Meyer’s treatment of paleontology has already been discussed in Ralph Stearley’s review. In this series of posts I will critically examine some features of Darwin’s Doubt that are of interest from the perspective of history and philosophy of science and the case he builds for Intelligent Design. I’ll start with how Meyer frames the current status of neo-Darwinian evolution. In subsequent posts, I will examine two important rhetorical strategies in Meyer’s argumentation and assess his design inference.
Neo-Darwinian Evolution under Attack
The scene is set in the prologue, where Meyer paints a picture of neo-Darwinian evolution as being under attack in the biology literature because it cannot explain macroevolution.Neo-Darwinian evolution (microevolution for Meyer) is a term often used to refer to random genetic variations plus natural selection, whereas macroevolution is the origin of new organs or body plans. According to him, a “host of distinguished biologists have explained in recent technical papers” that microevolution cannot give rise to macroevolution, and “an increasing number of evolutionary biologists have noted [that] natural selection explains ‘only the survival of the fittest, not the arrival of the fittest’” (p. x).
There is a sense in which Meyer is right that the adequacy of strict neo-Darwinian evolution (as he defines it) to produce macroevolution has been discussed in the biology literature. The impression he communicates to the reader is that scientists increasingly recognize this inadequacy and are searching for alternatives to neo-Darwinian evolution to “solve the problem.” Meyer argues that ID is the best available alternative. But the picture of the literature he paints leaves the reader with a mis-impression of the kind of revolutionary synthesis that seems to be shaping up in evolutionary biology.
To see this, let’s start with the quotation Meyer uses to great rhetorical effect, that natural selection explains “only the survival of the fittest, not the arrival of the fittest.” This quote comes from a paper by Gilbert et al. (1996)and certainly sounds as if natural selection is ineffective for explaining macroevolution. In their 1996 paper, Gilbert et al. recount the history of the rise of population genetics as the dominant understanding of evolution. As part of this story, embryology and macroevolution were displaced by or reduced to changes in gene frequencies as early forms of gene-centrism took over in evolutionary biology. That is, focusing on only the genetic underpinnings for change within a species was a hallmark of much early evolutionary theory. The history is fascinating, but the actual story these authors tell is different (and also much more interesting) than the impression Meyer gives.
Consider the passage from which Meyer cites the quote:
The Modern Synthesis is a remarkable achievement. However, starting in the 1970s, many biologists began questioning its adequacy in explaining evolution. Genetics might be adequate for explaining microevolution, but microevolutionary changes in gene frequency were not seen as able to turn a reptile into a mammal or convert a fish into an amphibian. Microevolution looks at adaptations that concern only the survival of the fittest, not the arrival of the fittest. As Goodwin (1995) points out, “the origin of species–Darwin’s problem–remains unsolved.” This reexamination of the Modern Synthesis has led to three great re-discoveries in modern biology. These are the simultaneous rediscoveries of macroevolution, homology, and the morphogenic field. A new synthesis is emerging from these three areas, and this developmentally oriented synthesis may soon be able to explain macroevolutionary as well as microevolutionary processes. The first condition for their rediscovery came from scientists such as R. B. Goldschmidt and C. H. Waddington, who saw that all changes important in evolution are alterations to development. (1996, p. 361, emphasis added)
The story that these biologists and historians of biology tell narrates a fairly typical episode in the course of theory development in the sciences–evolutionary biology in this case. Often when developing a new scientific theory, other relevant disciplines can be ignored or even dismissed if it’s thought that the new theory can replace those disciplines. This is what happened in evolutionary biology, where the field of genetics pushed aside embryology, developmental biology, and related disciplines. Sometimes scientists discover that a theory, such as population genetics, cannot replace the fields of study it initially displaced. Gilbert et al. tell the story of how embryology, developmental biology, and other fields have had to be brought back into evolution.
They go on to say that, “The homologies of process within morphogenic fields provide some of the best evidence for evolution–just as skeletal and organ homologies did earlier. Thus, the evidence for evolution is stronger than ever (p. 368, emphasis added). Moreover, they continue, natural selection “is merely a filter for unsuccessful morphologies generated by development” (p. 368). By “merely,” they mean that variations due to development are the main drivers of evolution, but natural selection ensures that developmental and other forms of genetic variations are filtered for what makes for sustainable ways of life for organisms. The overall picture of evolution is still one of variations filtered by natural selection. However, the sources of the most relevant variations, so they argue, are in developmental processes. The thrust of Gilbert et al., then, is a synthesis between neo-Darwinian and developmental biology. The synthesis these authors point to is much more developmentally-oriented, and that is revolutionary with respect to the old neo-Darwinian paradigm. But the emerging synthesis doesn’t leave genetic variations and natural selection out. Instead, developmental biology mediates between the functional biology of gene expression, cells, and anatomy, on the one hand, and the changes in gene frequencies of evolutionary biology, on the other (1996, p. 362). At the end of their article, Gilbert et al. write,
In declaring the morphogenetic field to be a major module of developmental and evolutionary change, we are, of course, setting it up as an alternative to the solely genetic model of evolution and development. This, however, is not to be seen as antagonistic to the principle that genes are important in evolution or development. This is not in any way denied. But just as the genes make the cells and the cells form the body, so the gene products first need to interact to create morphogenetic fields in order to have their effects. Changes in these fields then change the ways that animals develop. (p. 368, emphasis added)
Genes are what they are and do what they do largely due to their developmental context. That is, changes in the body or the environment throughout an organism’s lifetime can alter how genes are expressed, and these changes in gene expression sometimes affect fitness and thus evolution. The more accurate picture of the evolutionary and developmental biology literatures, according to Gilbert et al., is that evolutionary development and epigenetics along with other sources of genetic variation and natural selection are being forged into a new synthesis giving us insight into how both microevolution and macroevolution happen.
Another author Meyer cites in his critique of neo-Darwinian evolution, Wallace Arthur, a zoologist specializing in developmental biology, shares a similar vision as Gilbert, et al. Arthur actually argues against using any microevolution/macroevolution distinction for driving a wedge between genetic changes and the origin of higher taxa (Arthur 1997, chs. 2 and 8). Indeed, Arthur doesn’t see neo-Darwinian evolution and developmental biology as opposed to each other in contrast to the picture Meyer paints. Instead, he sees a kind of extended synthesis between the two branches of evolutionary study taking place:
True, neo-Darwinism has, to its detriment, been distinctly ‘non-developmental’. Yet there are parts of the theory which, when cast in a more developmental light, may have considerable explanatory power… essentially what I am proposing here is that Evolutionary Developmental Biology has the potential to form a bridge between population genetic processes and systematic patterns; and thus to help unify evolutionary biology in general. (p. 13-14)
Wallace thinks that developmental biology is contributing to neo-Darwinian evolution’s “missing developmental component” (p. 18).
Gilbert, et al., and Wallace are not alone. Many evolutionary and developmental biologists are pursuing an extended synthesis involving population genetics, developmental biology, epigenetics, and other recent developments. Yet Meyer presents their published research as offering an alternative to or replacement for neo-Darwinian evolution. It is true that some biologists, such as Jerry Coyne, dispute the importance of the contributions of evolutionary developmental biology and epigenetics, and continue to champion a fairly strict, gene-centric neo-Darwinian theory. But for every Coyne there is a Sean Carroll working out the kind of synthesis Gilbert et al. and Wallace are describing. It’s important to understand the difference between picturing the biology literature as working towards a new synthesis versus a literature that is developing mutually exclusive alternatives. Perhaps Meyers misreads the developing revolution as being one of several ideas competing to be the new paradigm, rather than as an emerging extended synthesis. The former picture is the basis for Meyer’s divide-and-conquer and question-shift strategies.
Earlier, we saw examples of how Intelligent Design (ID) advocate Stephen Meyer paints a picture in Darwin’s Doubt of the evolutionary literature as offering competing explanations for how evolution operates. One feature of his narrative is the claim that evolutionary development (evo-devo) raises profound difficulties for neo-Darwinian evolution. This way of framing the literature serves Meyer well rhetorically for his case advocating ID, and neo-Darwinian evolution alone does look inadequate to explain macroevolutionary change. However, his framing doesn’t make good sense of either the evolutionary or developmental biology literatures, or the paradigm shift that has been taking place within evolutionary biology the last three decades.
For example, the evo-devo authors Meyer cites view genetic variation and natural selection as being incorporated within evo-devo, not as outside and opposed to it. A popular audience reading Darwin’s Doubt will not be able to distinguish rhetorically created problems for evolution from the actual discussions in the biology literature.
The divide-and-conquer strategy works like this: First, Meyer rightly points out that there has been a long history of trying to understand the details of macroevolutionary change in neo-Darwinian evolution. Gilbert et al. (1996) gives a brief, but helpful account of this in the 20th century. Second, Meyer successively reviews a variety of attempts, such as evo-devo, to rectify this shortcoming in macroevolution (chs. 8-16). Each attempt surveyed is presented to the reader as being in competition with and a replacement for neo-Darwinian evolution (i.e., population genetics and natural selection). Third, Meyer assesses the “alternative” to the neo-Darwinian account and finds it lacking as a viable alternative for explaining the diversification of Cambrian body plans. Intelligent Design is left standing as the best possible explanation of the Cambrian explosion.
The divide-and-conquer strategy in Darwin’s Doubt, however, offers a misleading picture for the reader. As I pointed out above, researchers working in evo-devo typically don’t see themselves as replacing population genetics and natural selection. More generally, biologists, as illustrated by Gilbert et al., seek synthesis as the more fruitful approach to understanding descent with modification, where genetic variation and natural selection work along with other processes. Genetic variation and natural selection are seen as inadequate for descent with modification in the absence of these other processes. As Gilbert et al. put it, “macroevolutionary processes could not be explained solely by microevolutionary events” (p. 362, emphasis added). Microevolutionary processes are seen as contributing some of the necessary conditions for macroevolution, but, as has been widely recognized at least since the 1970s, are not sufficient conditions for macroevolution.
For detailed examples of how Meyer assesses evo-devo and the development of gene regulatory networks (GRNs) as independently inadequate to account for the macroevolution of new body plans in the Cambrian, see these supplementary materials. Neither the division nor the conquest parts of Meyer’s strategy work with respect to evo-devo or GRNs. These examples are representative of how the divide-and-conquer strategy functions for the other “alternatives” to classic neo-Darwinian evolution Meyer considers (e.g., epigenetics).
The Question-Shift Strategy
The second strategy playing a crucial role in Meyer’s case for ID is what I call the question-shift strategy. This strategy involves equivocating on the notion of origin. In the biology and palenotology literature, when scientists discuss the origin of Cambrian body plans, they mean the modification and diversification of body plans from preexisting body plans. This is the customary usage in the literature since Darwin’s publication of On the Origin of Species, where he makes clear that he is seeking only to explain speciation, not how the first species arose. The latter question is the origin of life issue, a separate question from how an ancestor species may be connected with descendant species though descent with modification. Meyer’s question-shift strategy is to shift from diversification of existing body plans to the origin of the first body plan. Yet, the question of how the first body plan arose isn’t what the biology and paleontology literature on the Cambrian is addressing.
A representative example of this question-shift strategy appears in Meyer’s discussion of whether changes in genes and genetic information might lead to new body plans. He critiques these accounts because they assume “the existence of significant amounts of preexisting genetic information…and then suggest various mechanisms that might have slightly altered or fused these genes together into larger composites. At best, these scenarios ‘trace’ the history of preexisting genes, rather than explain the origin of the original genes themselves” (p. 212, emphasis in the original).
Meyer and I would agree that the literature he surveys doesn’t answer origins of life questions. But note that he shifts the question from accounts of how existing genes may evolve to accounts of the origin of the first gene. He then faults this literature for not addressing the origins of the first genes. This equivocation on “origin” allows Meyer to critique studies of how genes diversify as inadequate to explain the advent of the first genes. Indeed, in a subsection titled “Begging Questions” Meyer accuses researchers in the literature of begging the question of the advent of the first genes by only considering mechanisms that could lead to modifications of preexisting genes (pp. 215-219). But it is Meyer who shifted the question from the one the literature addresses–the evolution of genes–to the advent of genes.
As a second example, consider Meyer’s claim that Erwin and Davidson (2009),
rule out both observed microevolutionary processes and postulated macroevolutionary mechanisms (such as punctuated equilibrium and species selection) as explanations for the origin of the key features of the Cambrian explosion. They insist that the requirements for constructing animal body plans de novo ‘cannot be accommodated by microevolutionary [or] macroevolutionary theory.’ (Meyer, pp. 355-356)
While Erwin and Davidson’s paper focuses on how preexisting gene regulatory networks might be diversified over time , Meyer’s use of “de novo,” here, in the absence of further qualification, shifts the average reader’s frame of reference from diversification of GRNs to the advent of the first GRN. Now, Erwin and Davidson do make reference to de novo generation of GRN sub-circuits, but what they mean is the redeployment of existing GRN circuits as a means of diversification (e.g., 2009, p. 145) rather than Meyer’s sense of de novo (first advent of a GRN; see supplementary materials).
These examples merely scratch the surface of the question-shift strategy in Darwin’s Doubt (three more examples are given in the supplementary material). Unfortunately, in each instance of the question-shift strategy, Meyer leaves his readers with the impression that the biology literature commits the fallacy of begging the question: of assuming an explanation for the advent of the first genes, GRNs, and body plans while only discussing the diversification of preexisting genes, GRNs, and body plans. Meyer is correct that the diversification mechanisms he surveys are inadequate for explaining advent of the first gene, GRN, or body plan.
Nevertheless, there is no question-begging going on in the literature, itself, because it’s addressing diversification questions. These are the Cambrian questions! The logical fallacy, here, is Meyer’s falling into equivocation on two different senses of “origin” and shifting all diversification questions to origin of life questions. Perhaps Meyer falls into the equivocation because of his fixation on the enormously challenging problem of origin of life. Nevertheless, it’s no fault of the biology and paleontology literature for failing to address Meyer’s first advent question. That’s the task of origin of life research and the subject of his book Signature in the Cell.
All Christians agree that the universe is designed; otherwise, we would not be able to say that this is God’s creation. Where we may differ is on the nature of that design and the how as well as on expectations for detectability of design. As we’ve seen, Meyer positions the evolution literature as inadequate to explain the origin of life so that Intelligent Design (ID) appears to be the best explanation for life on Earth.
Meyer’s rhetorical strategies, as we discussed earlier, lead up to his punch line in chapter 18:
As I have described the many attempts to explain the scientific enigma motivating this book, the mystery has, in one sense, progressively deepened. As more and more attempts to explain the Cambrian explosion of animal life have failed, the evidence that these various competing theories fail to explain may be considered a set of negative clues–evidence that effectively precludes certain possible causes or explanations [note the divide-and-conquer strategy]. I’ve already explained why the received version of evolutionary theory, neo-Darwinism, fails to account for the explosion of information and form in the Cambrian period. I’ve also examined more recent evolutionary theories and shown why they too fail to explain key aspects of the evidence [the question-shift strategy]. To this point, then, much of the evidence has returned a negative verdict. It has told us a lot about what, in all probability, did not cause the Cambrian explosion. But…an accumulating body of evidence that makes one set of explanations less and less plausible may also begin to paint a picture of an alternative cause and the true explanation. (p. 354, comments in square brackets added)
The divide-and-conquer strategy Meyer pursues does significant work in his case for ID as the best explanation of the proliferation of body plans in the Cambrian period. First, this strategy masks the extended synthesis that has been taking place in the last three decades between population genetics, developmental biology, and epigenetics. Second, as a consequence, this strategy makes it significantly easier to argue that an intelligent cause is the best explanation relative to population genetics, developmental biology, or epigenetics as independent, rival explanations for the diversification of body plans in the Cambrian. Meanwhile, the extended synthesis, which has vastly more explanatory power and supporting evidence than the imagined separation and competition among its components, is left out of the argument. What looks like a compelling case for ID turns out to be mere appearance.
Meyer’s question-shift strategy is similarly significant for his inference that ID is the best explanation for the “Cambrian explosion.” He repeatedly redirects the reader away from the spectacular work on how variations in pre-existing genes lead to new genes within the forming extended synthesis towards the open questions in origin of life research (e.g., how did DNA or the first gene arise?). Meyer then concludes that “attempts to explain the Cambrian explosion of animal life have failed” because these attempts fail to answer origin of life questions.
Since none of the evolutionary mechanisms Meyer surveys supposedly can answer the latter origin question, the divide-and-conquer and question-shift strategies lead to Meyer’s conclusion: “Either life arose as the result of purely undirected material processes or a guiding or designing intelligence played a role. Advocates of Intelligent Design favor the latter option and argue that living organisms look designed because they really were designed” (p. 340). By this point it’s clear to the reader that the diversification of body plans in the Cambrian never was Meyer’s target; the real target is the most challenging problem scientists face, the origin of life.
The door, then, appears to be open for the work of an intelligent agent as a more compelling explanation for the intricacies of living organisms. Here is a representative example:
Nevertheless, neither proponents of “evo-devo,” nor proponents of other recently proposed materialistic theories of evolution, have identified a mutational mechanism capable of generating a [developmental gene regulatory network] or anything even remotely resembling a complex integrated circuit. Yet, in our experience, complex integrated circuits–and the functional integration of parts in complex systems generally–are known to be produced by intelligent agents–specifically by engineers. Moreover, intelligence is the only known cause of such effects. Since developing animals employ a form of integrated circuitry, and certainly one manifesting a tightly and functionally integrated system of parts and subsystems, the necessary presence of these features in developing Cambrian animals would seem to indicate that intelligent agency played a role in their origin. (p. 364, square brackets added)
We can note several things about this comparison with engineering. First, the contrast is between materialist theories and intelligent agents. Here, we face an interpretive issue. On the one hand, Meyer might be using “materialist” to draw a contrast with an immaterial agency. But nowhere in Darwin’s Doubt (nor in Signature in the Cell) does he offer any defense for why the relevant intelligent agents must be immaterial. An inference to the best explanation that starts with everyday scientific activities and ends with an immaterial intelligence as the best explanation is a very large and startling inference indeed! On the other hand, by “materialist” Meyer might mean theories that draw only on unguided or naturalistic causes. If so, then there is a further issue as to whether such theories are metaphysically naturalistic (meaning they already presuppose that there are no spiritual beings or spiritual realm), or are only methodologically naturalistic (meaning they take the biological phenomena on their own terms to understand them as they actually are). Metaphysical naturalism goes far beyond any claims that could be licensed by scientific methods and should be opposed by all believers; methodological naturalism is the way scientific investigation has been done since before the time of the Scientific Revolution and is well-grounded theologically. Meyer certainly would be right to complain about metaphysical naturalism sneaking into scientific conclusions.
Second, the structure of the inference being suggested for the reader is that of a crime scene investigation (indeed, this is how chapter 18 is framed), or an anthropological or archeological investigation (Signature in the Cell draws explicitly on these, too). At first glance, these analogies with forms of human inquiry seem quite compelling given how Meyer has laid out his case. He argues that the complex integrated functionality of gene regulatory networks and other cellular machinery has a reasonable cause in an intelligent agent because such agents are known to be the causes of complex integrated functional systems in our experience (e.g., computers and cell phones).
Yet one problem with this line of inference is that it requires DNA, the genome, and so forth to literally be information-processing / integrated circuit systems operating based on programmed instructions; otherwise, the analogy with the complex integrated functional systems of our experience doesn’t hold. Certainly, it is true that such complex information-processing systems as computers have intelligent agents as their causes. However, language such as “information processing” and “integrated circuits” applied in the biology literature is ambiguous: Is it metaphorical or ontological? Biologists use such information-processing language in a variety of ways and often they use such language without specifying what they mean by it. What Meyer needs is an argument demonstrating that DNA, the genome, and so on ontologically are information processes systems. As metaphors, there is nothing about DNA implying that the context of the genome and the context of the complex integrated functional systems humans design and use are relevantly similar contexts. I see this as an area where there is further work to be done in making a compelling case for ID.
In the absence of that argument, what we have, here, is the fallacy of false analogy. The issue isn’t the level of complexity, though the genome is dazzlingly complex. Complex structures can develop over time through natural processes (e.g., a forested ecosystem developing on burned land over several decades). Rather, the issue is how strongly one can lean on terms that scientists use somewhat ambiguously to make ontological claims about the nature of DNA, the genome, and the like. Without a substantial argument for taking “information processing” and “integrated circuit” talk as ontological truths about the genome, there is no relevant similarity between the context of the genome and that of human-designed information processors.
Third, there are two basic problems with how Meyer compares crime scene investigation, anthropological, and archeological investigations with biological investigation. While it is the case that crime scene investigation offers some wonderful examples of scientific methods, it’s important to note that crime scene investigators already presuppose that a person is the cause of the crime. Similarly, anthropologists and archeologists already assume that human activity is involved. Human intelligence is a presupposition that is internal to such of forms of inquiry. In contrast, an intelligent agent is a presupposition external to cellular and evolutionary biology; intelligence has to be brought in from the outside. This means that when Meyer frames the inference for intelligent agency as a crime scene investigation (or as archeological investigation), the activity of an intelligent agent is now a presupposition for biological inquiry. This is a presupposition biologists rightly object to.
Moreover, Meyer ignores the differences in context between natural science inquiry in biology and chemistry, on the one hand, and human inquiry, on the other. Meyer’s inference that intelligent agency is the best explanation for the Cambrian explosion depends crucially on taking natural science and human inquiry to be the same. But this is to ignore important differences between these two forms of inquiry and their subjects of study. The most important distinction is that natural science inquiry objectifies its subjects of inquiry (e.g., electrons) deploying methods that treat every object of inquiry as related only via forces or other processes, where values and ideals are absent from those forces and processes. That is to say, natural science inquiry treats its objects of study as bundles of properties in a manner abstracted away from the richer contexts of human concerns. However, applying this form of objectification to agents is anything but value-free when applied to inquiry about persons. For instance, astronomers can study the physics of star formation without any judgments about whether it would have been morally better for the star to have formed in a different location. And molecular biologists can study a molecular pathway without any judgments about whether it would have been morally better for the pathway’s reaction to be faster than it is. Whenever we turn to the study of persons, however, we can never avoid some form of moral judgment. Even the act of objectifying persons doesn’t avoid moral judgments: To study persons the same way we study stars and molecular pathways is a whopper of a moral judgment! The objectification that Meyer assumes is particularly problematic when God is the object of inquiry, being treated as no different in kind from chemical molecules as an object of study. Meyer’s appeal to crime scene and other forms of human inquiry is neither as innocent nor straightforward as it appears.
If we set aside the divide-and-conquer and question-shift strategies and take the biology literature that Meyer surveys on its own terms, then the argument for ID looks much weaker. The reader may perceive that there has been a bait and switch in Darwin’s Doubt. Charles Marshall’s review of Darwin’s Doubt in Science last year suggests that the problems in Meyer’s book are due to his “true belief” in an Intelligent Designer. And Meyer provides plenty of evidence for this conclusion.
He systematically paints the evolutionary biology literature as challenging neo-Darwinian evolutionary theory, mistaking the normal process of theory development and modification for admissions of “weaknesses” in or “criticisms” of evolutionary theory. His case for “weaknesses” and “scientific criticism” is bolstered by selective quotations from the literature under the divide-and-conquer and question-shift strategies. An informed reader gets the impression that Meyer reads the literature hunting for support for his pre-conceived view rather than in search of insight into what evolutionary and developmental biologists are actually saying.
This hunting for ammunition can lead to claims such as “The technical literature in biology is now replete with world-class biologists routinely expressing doubts about various aspects of neo-Darwinian theory, and especially about its central tenant, namely, the alleged creative power of the natural selection and mutational mechanisms,” and that there is a “growing body of critical scientific opinion about the standing of the theory” (p. x). Three remarks are in order regarding Meyer’s claim. First, as Gilbert et al. (1996) make clear, they are focusing on an extended synthesis with natural selection and mutations. Second, the world-class biologists Meyer references (e.g., Simon Conway Morris) roundly reject Meyer’s assessment of what they themselves are saying. For instance, Meyer has cited Gilbert and others to the effect that current evolutionary theory is inadequate to explain macroevolution before, but as they have pointed out, they make no such claims.
Third, to say that there is a “growing body of critical scientific opinion about the standing of the theory” is misleading. A fundamental problem is that Meyer mistakes the normal scientific processes of investigating, revising, and extending a theory for “raising doubts” about the theory. The work of historians and philosophers of science as diverse as Thomas Kuhn and Phillip Kitcher have helped us recognize the normal business of scientific theory development is complex and rather messy. However, it’s possible that when hunting for support for a pre-conceived view one might mistake this messy process for “raising doubts” about a theory.
Clearly the kind of mischaracterization in Darwin’s Doubt is rhetorically important: It makes mainstream evolutionary biology look much weaker and more confused than it actually is. So, when Cornelia Dean writes that “There is no credible scientific challenge to the theory of evolution as an explanation for the complexity and diversity of life on earth” (quoted by Meyer, p. xi), she exhibits a much better grasp of the practices of biologists and the biology literature than Meyer does.
From a history and philosophy of science standpoint, Meyer’s way of framing things is disturbing. Every scientific paradigm is incomplete and always under development. Evolution is no different. It’s been well-known for decades among evolutionary biologists that macroevolution was a promissory note that was expected to be fulfilled as they continued to develop and extend the neo-Darwinian paradigm. More questions than solutions have been generated about the connections among genetic variations, natural selection, and the origin of higher taxa; but this is standard fare for any scientific theory (e.g., we have more questions about Einstein’s theory of general relativity than we did in previous decades as physicists continue to develop and extend the theory). The picture of evolutionary theory and developmental biology presented by Meyer doesn’t help us understand what scientists working in those areas actually do and what their debates actually are about. Nor does his framing help us understand whether evolutionary and developmental biology needs explicit reference to an observable intelligent cause.
The biology literature that Meyer surveys actually exhibits a remarkable self-critical sifting that makes theory development possible. Scientists test and correct one another’s ideas and continue to develop their theoretical frameworks. Gilbert et al. (1996) illustrates this beautifully, laying out a narrative of self-reflection, testing, and theory development in action as the story of the return of embryology and homology to evolutionary biology. This story is particularly relevant, because the discoveries we’ve made in evolutionary development the last thirty years provide eye-popping examples of why it’s important to recognize how even the most well supported theories in science can change and become stronger when evidence from seemingly unrelated fields provide unlooked-for contributions. (For instance, the discovery that deleting specific regulatory gene sequences leads to the production of a reptilian jaw in mice (Gilbert et al. 1996, p. 364)—exactly the sort of thing one would expect if regulatory networks played crucial roles in channeling embryological development.)
Where Is God in All This?
Finally, there is a theological issue to all of this. Many Christians are strongly supportive of ID, but should they be? ID eschews the Bible and theology, taking a thoroughgoing secularist approach to the quest for evidence for intelligent causes in nature. Such a secularist view obscures the status of nature as creation, an arena of Triune care and action (see my article). Moreover, ID focuses solely on scientific methods as the only viable means for detecting intelligent causes in nature. This cedes far too much to scientism, reflecting the dominant technocratic ethos of the times rather than a reflective Christian approach to understanding the Triune God’s relationship to creation.
Recall Meyer’s dichotomy highlighted earlier: “Either life arose as the result of purely undirected material processes or a guiding or designing intelligence played a role. Advocates of Intelligent Design favor the latter option and argue that living organisms look designed because they really were designed” (p. 340). Our choice appears to be either intervention from outside, beyond natural processes, or natural processes with no intelligent influence whatsoever. Yet, this is a false choice. Those pursuing evolutionary creation approaches (e.g., B. B. Warfield) have been exploring theologically robust alternatives where God is active in creation through the very processes of evolution. Passages such as Genesis 1:24-25, Psalm 104, Job 38-42, among others, picture God and creation both at work. Indeed, Genesis 1 affirms that the Earth functions to originate life, not just reproduce it. All of this takes place under the superintendence of the Son and enablement of the Spirit.
Therefore, when biologists investigate evolution, development, and other biological processes, they are exploring the functionality of God’s creation and theorizing about God’s normal ways of working in the world (see my white paper). Many scientists don’t understand that this is what they’re doing, but there is no way to avoid it because they are studying a creation designed by our Triune Creator. This doesn’t mean that scientists always get things right; all scientific knowledge is provisional. But it does mean that Christians don’t face the false choice presented in Darwin’s Doubt between evolutionary science and God.