The Ancestor’s Tale

Article ID: JAE231 | By: Angus Menuge

This review first appeared in the Christian Research Journal, volume 29, number 4 (2006). For further information or to subscribe to the Christian Research Journal go to: http://www.equip.org

Richard Dawkins is professor of the Public Understanding of Science at Oxford University. He is best known for a series of books that popularize and defend an orthodox Darwinian view of the origin and diversity of life, including The Selfish Gene (1976) and The Blind Watchmaker (1986). An outspoken atheist, Dawkins gained notoriety as “Darwin’s Rottweiler” for declaring the critics of evolution “ignorant, stupid or insane.”1 Dawkins is also a gifted communicator, however, whose books reach out to nonscientists by avoiding technicalities and employing literary themes. In The Ancestor’s Tale, Dawkins adapts the literary structure of Geoffrey Chaucer’s Canterbury Tales. Chaucer used a geographical pilgrimage (from London to Canterbury Cathedral) as a clever device to reveal the diversity of English life and to satirize its foibles. Dawkins similarly uses a pilgrimage back in time to survey the diversity of all life from a Darwinian perspective, starting with present-day humans and ending with the beginning of life, allowing each branch in the tree of life to tell its “tale.” In the process, Dawkins satirizes the religious view that there is something special about human beings, since Darwinian evolution had no goal of producing humans and ours is only one of many pilgrimages.

At each junction in the tree of life, the pilgrims we join are termed “concestors.” A concestor is (going backwards in time) the last common ancestor shared by a set of species: thus, allegedly, Concestor 0 is “the most recent common ancestor of all living humans” (p. 41); Concestor 1 is the most recent ancestor of chimpanzees, bonobos and humans; and Concestor 39, the last of the concestors, is eubacteria. Canterbury itself, for Dawkins, is nothing sublime or holy, but the origin of the first self-replicating molecules from inorganic chemicals.

Distinctively Human. Dawkins agrees with Christians that modern humans have some unique features, including highly developed language and culture, but he supposes these arose from a series of mutations, perhaps in the FOXP2 gene (70), that caused an enormous change in the brain: “It turns out that the modern human brain is about six times as big as it should be, for a mammal of equivalent size” (83). From a Darwinian perspective, the superiority of humans is not due to the fact that humans are made in the image of God; rather, each of a sequence of random changes provided an incremental advantage that together resulted in our current capacities.

This is perhaps the most unconvincing thesis of the book, because rationality and language use require highly coordinated faculties, which is just what Darwinian accounts have difficulty in explaining. For example, in order to follow a logical argument, all of our evidence (premises) must be brought together and the conclusion drawn from them in a unified consciousness. Language use, likewise, requires us to coordinate a series of words to form a single thought. As Dawkins’ insists, however, Darwinian evolution has no plan or foresight, and can only “build” features by a sequence of slight modifications, since large-scale changes that happen to be adaptive are far too improbable. As a result, Darwinian evolution has no means of coordinating the modifications so that they jointly achieve a coherent task.

In fact, Dawkins and psychologist Steven Pinker both have argued that on a Darwinian view, the human brain is just an assemblage of useful gadgets or modules, each of which is there because it has provided some advantage to our genes, but that there is no single seat of consciousness where thought comes together.2 There are, rather, multiple concurrent tracks of information processing going on in all of the various modules. As I have argued in my book Agents Under Fire,3 this fails to account for the fact that an act of reasoning unifies an agent’s information into a coherent set of reasons so that he or she can draw a logical conclusion.

Panglossian Naturalism. The most enjoyable part of The Ancestor’s Tale is its account of the biological machines whose sophistication often surpasses the best efforts of human engineers. It may look comical, but the bill of a duckbill platypus, for example, is a highly sophisticated device that can detect the electrical fields generated by creatures buried in the mud (235–40). More generally, Dawkins notes, “Whenever humans have a good idea, zoologists have grown accustomed to finding it anticipated in the animal kingdom,” including, for example, “echo-ranging (bats)…the dam [beavers]… the infrared heat-seeking sensor (some snakes), the hypodermic syringe (wasps, snakes and scorpions), the harpoon (cnidarians) and jet propulsion (squids)” (545). Nature is so full of advanced technology that there is a whole field known as biomimetics, which seeks to apply natural engineering solutions to human problems.4

Dawkins confidently ascribes this engineering prowess to natural selection; yet, the evidence he presents is insufficient for such Panglossian optimism.5 Biochemist Michael Behe has argued, for example, that complex molecular machines often are irreducibly complex, because they have a number of specific well-matched parts, the loss of any one of which would remove function. Dawkins himself also emphasizes the huge gaps between functional living creatures: “Living creatures are islands of viability separated from other islands by gigantic oceans of grotesque deformity” (445). These gaps make it difficult to see how one complex, viable creature can be gradually transformed into another, since small changes cannot be coordinated and, as Dawkins says, “A random change of sufficient magnitude to initiate a new phylum [i.e., biological classification] at one fell swoop will be so large…that it would have to be preposterously lucky to land on another island of viability” (445).

Gaps in the Record. Dawkins is confident that many small changes can do the job, but this assumes a series of viable “stepping stones” between biological phyla (i.e., primary divisions). This assumption is not supported by the fossil evidence, however, which contains many gaps where evolutionists believe the intermediary (transitional) forms should be. Dawkins, like Darwin, tries to explain this away as “an inherent consequence of the way sedimentary rocks are made” (72). The rarity of fossils in general, however, is not an explanation of the fact that of those fossils we do have, few if any are convincing transitionals. Darwin himself admitted that his theory implies the existence of “innumerable transitional forms,”6 precisely because evolution is so gradual. Darwinism, therefore, predicts that the proportion of transitional forms should always be high in any unbiased sample that we take; but it is not.

Dawkins only makes his case worse by conceding that biological classification would be impossible without gaps because if there were no gaps there would be no clear boundaries between species (310). What this really means is that there is overwhelming evidence of these clear boundaries, but that there can be no such boundaries if Darwinism is true. It seems at times that Dawkins is not really testing the Darwinian view against the observable facts, but rather rationalizing the unobserved facts according to the Darwinian view, and determining what the facts must be if that view is true. This is particularly clear in his discussion of the Cambrian explosion, that is, the sudden appearance of diverse biological kinds during the Cambrian period. Darwinian evolution claims that there are no insurmountable boundaries between biological kinds, so that we would expect major phyla (such as chordates, crustaceans, and other arthropods) to develop gradually from more primitive ones (such as echinoderms and mollusks). In Cambrian strata, however, we find fossils of nearly all of the major biological phyla, but do not find more primitive creatures outside those phyla. This lack of evidence does not trouble Dawkins because Darwinian theory reassures him that “those antecedents had to be there, but they have not been discovered. Whatever the reason, and whatever the timescale, they failed to fossilize, but they must have been there” (446, emphasis added).

It’s in the Genes. Dawkins does not limit his discussion to fossils, but appeals to genetics as well. To those who doubt that random mutations can provide novel biological information, he replies, “Accidental DNA duplication is one of the major sources of new genes” (155). Behe and Snoke point out, however, that “although gene duplication and point mutation may be an effective mechanism for exploring closely neighboring genetic space…this…is problematic when multiple mutations are required.”7

Dawkins also seems to think that genes are the dominant factor in determining a creature’s development and in explaining the diversity of body plans (184–86). He even says, “A ‘phenotype’ is that which is influenced by genes. That pretty much means everything about a body” (186). Embryologist Jonathan Wells has pointed out, however, that there is strong evidence that genes do not dictate development, including such facts as that “similar developmental genes are found in animals as different as worms, flies and mammals,” and that “eggs contain several structures…that are known to exercise control of development independently of the DNA.”8 Stuart Newman and Gerd Müller, likewise, argue that the organization of body plans cannot be explained purely by genes because “phenotypic outcomes persist despite extensive derangement in lines of ‘program code.’”9 In fact, they argue that “neo-Darwinism has no theory of the generative. As a consequence, current evolutionary theory can predict what will be maintained, but not what will appear.”10

Top-Down Design. Dawkins agrees with proponents of intelligent design that nature is full of apparently designed systems, ones that have all the characteristics of human artifacts; but he thinks this is merely the byproduct of an “arms race” between competing life forms. Natural selection explains ever more efficient methods of predation (i.e., preying on other life forms) and evasion of predation, enhancing the “illusion of design” (601). The problem is that there is strong evidence of top-down design that is in accord with a plan, rather than bottom-up design that is by trial-and-error. Dawkins agrees with Simon Conway Morris that many creatures independently develop the same solutions to the same kind of problems (called “convergent evolution”): for example, the eye “has evolved independently more than 40 times” (388). This argues, however, that these features are explained by the organism’s top-down functional requirements and not its undirected trajectory through biological space.

There is also the problem, which Behe has noted, of the irreducible complexity of some biochemical structures, such as the bacterial flagellum, which functions as a sort of molecular outboard motor, complete with engine, drive shaft, bushings, and propeller. It is very hard to see how such a tightly integrated system could develop gradually, as Darwinism requires, because it needs a large number of highly specific, “well-matched” parts in order to function. Dawkins agrees that the bacterial flagellum is an engineering marvel, but dismisses irreducible complexity as an “argument from personal incredulity” (549). He defers to the work of Kenneth Miller (a biologist at Brown University and author of Finding Darwin’s God) to show that the flagellum could have developed gradually after all. Miller points out that many bacteria have a mechanism for injecting chemicals into host cells called the TTSS (Type Three Secretion System), and that this system “uses a subset of the very same proteins that are used in the flagellar motor” (550–51). Perhaps the flagellum’s locomotion system developed indirectly, by co-opting a TTSS.

Scott Minnich (an expert on the flagellum) and Stephen C. Meyer (a philosopher of science) have shown, however, that this response is inadequate. For one thing, the transitional system would need more than one TTSS, and “possessing multiple TTSSs causes interference.” Further, “the other thirty proteins in the flagellar motor…are unique to the motor and are not found in any other living system. From whence, then, were these protein parts co-opted?” They add, finally, “even if all the protein parts were somehow available…the parts would need to be assembled in the correct temporal sequence…Arguably this [assembly] system is itself irreducibly complex.”11

Dawkins argues that we must reject design in science because it provides no explanation: “Ultimately, design cannot explain anything because there is an inevitable regression to the problem of the origin of the designer” (602). There are at least two problems with this argument: First, everyone, including Dawkins, believes in some fundamental principles that explain, but that themselves cannot be explained further. Dawkins tries to explain everything by appeal to chance (mutations) and necessity (natural selection by the laws of nature). If his argument were correct, we could protest that chance and necessity do not explain anything because they have not been explained, but simply assumed. Second, Dawkins assumes that all designers have an origin. This assumption also is not explained, however, and no one who believes in God would grant its truth.

On the negative side, The Ancestor’s Tale fails to engage convincingly with the best critics of Darwinism. Many readers also will dislike the numerous, self-indulgent asides on American politics. On the positive side, The Ancestor’s Tale is that rare thing, a beautifully written and highly entertaining book about science. Despite its ideological slant, the volume contains a lot of accurate up-to-date factual information and reports on the current theories and controversies in biology in accessible terms. It is worth reading just for what it reveals about the wonderful diversity of life.

— reviewed by Angus Menuge

NOTES

1. Richard Dawkins, “Put Your Money on Evolution,” New York Times, April 9, 1989.

2. Richard Dawkins and Steven Pinker, “Is Science Killing the Soul?” (debate, Westminster Central Hall, London, February 10, 1999), Edge 53 (April 8, 1999), available online at http://www.edge.org/documents/archive/ edge53.html.

3. Angus Menuge, Agents Under Fire: Materialism and the Rationality of Science (Lanham, MD: Rowman and Littlefield, 2004).

4. See Rhett Butler, “Biomimetics: Technology That Mimics Nature,” Mongabay.com, http://news.mongabay.com/ 2005/0711-rhett_butler.html.

5. Dr. Pangloss is a character in Voltaire’s philosophical tale Candide (1759) who is satirized for his overly optimistic view of the world that is blind to its many evils.

6. Charles Darwin, “Difficulties on Theory,” in Origin of Species (1859; repr., New York: Gramercy, 1979), 206.

7. Michael J. Behe and David W. Snoke, “Simulating Evolution by Gene Duplication of Protein Features…,” Protein Science (2004), 13: 2651–64.

8. Jonathan Wells, “Making Sense of Biology: The Evidence of Development by Design,” in Signs of Intelligence, ed. William A. Dembski and James M. Kushiner (Grand Rapids: Brazos Press, 2001), 121.

9. Gerd B. Müller and Stuart A. Newman, Origination of Organismal Form (Cambridge, MA: MIT Press, 2003), 6.

10. Ibid., 7.

11. Scott A. Minnich and Stephen C. Meyer “Genetic Analysis of Coordinate Flagellar and Type III Regula­tory Circuits in Pathogenic Bacteria” (paper presented at the Second International Conference on Design and Nature, Rhodes Greece, September 1, 2004), http://www.discovery.org/scripts/viewDB/index.php?command=view&program=CSC Scientific Research and Scholarship – science&id=2181.