Book review: River Out of Eden: A Darwinian View of Life
by Richard Dawkins, Basic Books, New York
by Raymond G. Bohlin
The DNA ‘River’
Richard Dawkins’ exposition of a Darwinian view of life in
River Out of Eden certainly fits into the overt anti-theism category. His
River Out of Eden is a river of DNA that is the true source of life and
the one molecule that must be understood if life is to be understood.
This river of DNA originally flowed as one river (one species) which eventually
branched into two, three, four, and eventually millions of rivers. Each river is
distinct from the others and no longer exchanges water with the others, just as
species are isolated reproductively from other species. This metaphor allows Dawkins
to explain both the common ancestry of all life, along with the necessity of gradualism
in the evolutionary process.
The commitment to gradual evolution is no surprise coming from Dawkins, but he forces
himself to do some rather grotesque hand-waving when he chooses to discuss the Cambrian
explosion. He notes that some in the past have suggested that the Cambrian creatures
may have evolved by some unknown mechanism, since gradual Darwinism simply can’t
achieve the level of diversity in the Cambrian in only 5–10 million years.
Dawkins exclaims:
The fallacy is glaring! Even creatures as radically different from one another as
mollusks and crustaceans were originally just geographically separated populations
of the same species. For a while, they could have interbred if they had met, but
they did not. After millions of years of separate evolution, they acquired the characteristics
which we, with the hindsight of modern zoologists, now recognize as those of mollusks
and crustaceans respectively.
This simply glosses over the evidence of sudden appearance of radically different
body plans that give no hint of having recently been geographically isolated forms
of the same species. Simply saying with gusto that the ‘fallacy is glaring’
does not make it so.
Dawkins also refers to this river of DNA as a digital river. That is, the information
contained in the DNA river is completely analogous to the digital information of
languages and computers. Chapter 1 contains an excellent discussion of the differences
between analogue codes and digital codes, and why DNA fits the digital model.
Surprisingly, Dawkins gives away the store in this first chapter. In pressing home
the digital analogy, Dawkins first uses probability to indicate that the code arose
only once and that we are all, therefore, descended from a common ancestor.
The odds of arriving at the same 64:21 (64 codons:21 amino acids) mapping twice
by chance are less than one in a million million million million million. Yet the
genetic code is in fact identical in all animals, plants and bacteria that have
ever been looked at. All earthly living things are certainly descended from a single
ancestor.
So it is reasonable to use probability to indicate that the code could not have
arisen twice, but there is no discussion of the probability of the code arising
by chance even once. A curious omission! If one tried to counter with such a question,
Dawkins would predictably fall back on the assumption of naturalism, that since
we know only natural processes are available for the origin of anything, the genetic
code must have somehow beaten the odds.
Even more glaring is Dawkins’ attempt to awe the reader with the precision
of the DNA code by using the illustration of an imprisoned molecular biologist.
After being forced to work in a biological-warfare lab by an evil power, the biologist
engineers a virus that contains a coded message in the DNA, utilising the 64 codons
for the 52 upper and lower case letters of the alphabet plus punctuation marks,
explaining his predicament. The coded message is flagged by the use of an easily
recognisable sequence, the first 10 prime numbers. The scientist infects himself
with the virus, sneezes on others in the lab and the virus is eventually spread
around the world. In attempting to halt the spread of the epidemic, scientists sequence
the entire genome of the virus and are alerted to the presence of the coded message
by an odd repeated pattern.
Alerted by the prime numbers —which cannot have arisen spontaneously
— somebody tumbles to the idea of deploying code-breaking techniques. From
there it would be short work to read the full English text of Professor Crickson’s
Message, sneezed around the world. [Emphasis mine.]
Amazing how the simple series of the first 10 prime numbers cannot have arisen in
the genetic code by chance, but the very code itself can. I believe the emperor
has no clothes!
Common DNA Ancestor?
Chapter 2 attempts to tell the story of the now famous ‘African Eve’,
the idea that we are all descended from a single female, probably from Africa, about
100,000 years ago. This conclusion originates from sequence data of the DNA contained
in mitochondria. Mitochondria, hence mitochondrial DNA, are inherited maternally.
The sperm injects only nuclear DNA into the egg cell; therefore all our mitochondria
are inherited from our mother. Therefore, an analysis of mitochondrial DNA reveals
maternal history only, uncluttered by the mixture of paternal DNA. Dawkins thus
takes us on a rather tortuous route to prove that we are all (maternally) descended
from one individual regardless of whether we know who that is.
Finally, Dawkins makes his case for the reliability of molecular phylogenies. Here
he glosses over weaknesses in the theory and actually misrepresents the data. On
page 43 he says,
On the whole, the number of cytochrome c letter changes separating pairs of creatures
is pretty much what we’d expect from previous ideas of the branching pattern
of the evolutionary tree.
Later on page 44 when speaking of all molecular phylogenies performed on various
sequences,
They all yield pretty much the same family tree — which by the way, is rather
good evidence, if evidence were needed, that the theory of evolution is true.
Besides implying that evidence is not really needed to prove evolution, Dawkins
stumbles in trying to display confidence in the molecular data. What exactly does
‘pretty much’ mean anyway?
He makes the errant claim that the differences in speed of evolution exhibited by
different proteins and genes reflect the degree that a protein can tolerate amino
acid substitutions. The less a protein can tolerate changes in its amino acid sequence
and still perform its function, the fewer the number of substitutions over millions
of years. In other words, the greater the functional constraints on a protein the
less variation over the years; the fewer the constraints, the greater the variation.
But the idea of functional constraints has not been verified by the data, which
of course Dawkins does not bother to mention. Michael Behe reported in 1990 that
the histones, thought to be the most functionally constrained proteins known, tolerate
deletions and substitutions quite well.1
While this chapter contained the usual degree of arrogance from Dawkins, particularly
in his disdain for the original account of Adam and Eve, it was somewhat less compelling
or persuasive than is his usual style. He hedged his bet frequently and simply waived
his hand at controversy. Unfortunately, this may not be picked up by the unwary
reader.
The ‘Problem’ of Design
In Chapter 3, ‘Do Good by Stealth’, Dawkins launches a full-scale assault
on the argument from design. After presumably debunking arguments from the apparent
design of mimicry (not perfect design, you know, just good enough) Dawkins states,
Never say, and never take seriously anybody who says, ‘I cannot believe so-and-so
could have evolved by gradual selection." I have dubbed this fallacy "the
Argument from Personal Incredulity.’
To some degree I’m afraid that many creationists have given Dawkins and others
an easy target. Such a statement, ‘I cannot believe . . .,’
has been used many times by well-meaning creationists but is really not very defensible.
It is not helpful to simply state that you can’t believe something; you must
elaborate the reasons why.
First, Dawkins levels the charge that much of what exists in nature is far from
perfectly designed and is only good enough. This he claims is to be expected of
natural selection rather than a designer. His examples include the mimicry of orchids
to appear and smell like a female wasp to elicit copulating behaviour by the male
wasp and thereby pollination of the orchid, the red belly of male sticklebacks to
attract a female, gull parenting and feeding behaviour, and other lesser examples.
Dawkins painstakingly assembles plausible sequences to indicate that it is not all
that difficult to envision a process of natural selection and mutation to account
for these wonders of the natural world.
To begin with, the lack of perfection in no way argues for or against a designer
or natural selection. I have always marvelled at some evolutionists who imply that
if it isn’t perfect, then Nature did it. Just what is perfection? And how
are we to be sure that our idea of a perfect design wasn’t rejected by the
Creator because of some flaw we cannot perceive? It is a classic case of creating
God in our own image. The evolutionists are the ones guilty of erecting the straw
man argument in this instance. In addition, Dawkins fully admits that these features
work perfectly well for the task at hand. The Creator only commanded His creatures
to be fruitful and multiply, not necessarily to be perfectly designed (humanly speaking)
wonders. Romans 1:18–20
indicates that the evidence is sufficient if you investigate thoroughly.
Dawkins oversimplifies the complexities in each case history. For example, in the
wasp/orchid mimicry, he claims that maybe the wasp doesn’t need a perfect
mimic of a female to get the process started. He illustrates how easy it is to sexually
arouse human males and concludes on page 62,
Perhaps a fleeting view of a female is all a fast-flying wasp can expect to get
before attempting to copulate with her. Perhaps male wasps notice only a few key
stimuli anyway.
But if it doesn’t need to be perfect, why does it appear to be so? Why has
the orchid wasted so much energy approaching perfection when it is not needed? And
where did the genetic capacity for genetic variation in orchids that allow for such
diversity come from? Other flowers show variety in colour, but no variety at all
in shape. Orchids show amazing diversity in both colour and shape. This indicates
a tremendously complex genetic system to allow for such diversity. There is more
to consider than just the wasp. One must also calculate the difficulties for the
orchid as well. Dawkins ignores the complexities of this part of the equation. And
finally, just what does human sexual response have to do with wasps anyway?
Later on page 67, after explaining the limits of wasp eyesight, Dawkins reasons
that
At least in some respects, then, wasps are easy to fool. It is a very different
kind of fooling from that engineered by the orchid. . . . If insect eyesight is
so poor, and if wasps are so easy to fool, why does the orchid bother to make its
flower as wasp-like as it is? Well, wasp eyesight is not always so poor.
Well there you have it, wasp eyesight is poor enough to get mimicry started, but
not so poor as to be always fooled and, therefore, needs further perfection by the
orchid to keep the process going. Someone is having their cake and eating it too!
Another aspect of Dawkins’ argument that struck me concerned his contention
that wasps and other insects see the world very differently than we do, and we shouldn’t
presume that our view of perfection will be the same as theirs. This exemplifies
an evolution-ary philosophical conundrum that is rarely addressed. Our eyesight,
and concomitantly our brain, has presumably been shaped by evolution to interpret
the world in such a way as to aid in survival and reproduction, not necessarily
as it really is. Perhaps the insects perceive reality better than we do. How can
we know? C. S. Lewis quotes from J. B. S. Haldane’s Possible Worlds:
If my mental processes are determined wholly by the motions of atoms in my brain,
I have no reason to suppose that my beliefs are true ... and hence I have no reason
for supposing my brain to be composed of atoms.
2
Ultimately, within philosophical naturalism, there is no truth. So why try to persuade
anyone of anything?
In pages 78–82 Dawkins then moves to the eye and utilises a computer simulation
experiment performed by Dan Nilsson and Susanne Pelger to demonstrate how easy it
would be to evolve vertebrate (camera) eyes. They claimed that it would take less
than 0.5 Ma to evolve such an eye, if it evolved in animals with one generation
per year. Again, Dawkins’ explanation can be very convincing until you begin
asking some questions. For instance, Dawkins begins with three layers of specialised
tissues. Where did these come from? Dawkins waves his hand and says you have to
start somewhere. But these are already completely ignored. The programme is set
to run by accumulating changes in the structure of these tissues, with the only
criterion being that the changes must be small and an improvement on what went before.
‘Improvement’ was defined as the visual acuity or spatial resolution
of the image, which can be calculated as a single real number. However, as Dr George
Marshall, Jules Thorn Lecturer in Ophthalmic Science at the University of Glasgow,
Scotland, points out:
. . . even if there is an eye, it will be useless unless the organism has the neural
and/or mental processes to utilize information perceived by the eye. How can a chance
mutation provide this complexity in several different structures.3
However, just because something is an ‘improvement’ is no guarantee
that the change is significant enough to be selected for in a population.4
Dawkins then makes a pitch for the necessity of gradualism in evolution. On page
83 he states,
A key feature of evolution is its gradualness. This is a matter of principle rather
than fact. . . . Evolution is very possibly not, in actual fact, always gradual.
But it must be gradual when it is being used to explain the coming into existence
of complicated, apparently designed objects, like eyes. For if it is not gradual
in these cases, it ceases to have any explanatory power at all. Without gradualness
in these cases, we are back to miracle, which is simply a synonym for the total
absence of explanation.
Dawkins proclaims that his explanation is the only game in town, by definition.
And he is doing the defining. Intelligent design does have explanatory power, as
was dramatically demonstrated by the contributors to The Creation Hypothesis.5
Dawkins further closes off criticism by declaring that
There will be times when it is hard to think of what the gradual intermediates may
have been. These will be challenges to our ingenuity, but if our ingenuity fails,
so much the worse for our ingenuity.
So if explanations fail us, the fault is not with the evolutionary process, just
our limited thinking. How convenient that the evolutionary process is so unfalsifiable
in this crucial area. But this is science and intelligent design is not!
Dawkins concludes the chapter with a discussion on the evolution of the honeybee
waggle dance. It is filled with probabilistic statements like
The suggestion is that . . . Perhaps the dance is a kind of . . . It is not difficult
to imagine . . . Nobody knows why this happens, but it does . . . It probably provided
the necessary . . . [!]
Yet at the end, Dawkins proclaims,
we have found a plausible series of graded intermediates by which the modern bee
dance could have been evolved from simpler beginnings. The story as I have told
it . . . may not be the right one. But something a bit like it surely did happen.
Again, ‘it happened’ only because any other explanation has been disallowed
by definition and not by the evidence.
Why Purpose?
Dawkins concludes his attack on design with a more philosophical discussion in Chapter
4, ‘God’s Utility Function’. He begins with a discussion of the
ubiquitous presence of ‘cruelty’ in nature, even mentioning Darwin’s
loss of faith in the face of this reality. Of course his answer is that nature is
neither cruel nor kind, but indifferent. That’s just the way nature is.
But a curious admission ensues from his discussion. And that is, ‘We humans
have purpose on the brain.’ Dawkins just drops that in to help him
put down his fellow man in his usual arrogant style. But I immediately asked myself,
Where does this ‘purpose on the brain stuff’ come from? The rest of
nature certainly seems indifferent: why is it that man, within an evolutionary world
view, has ‘purpose on the brain?’ In his attempt to be cute, Dawkins
has asked an important question: why is man unique in this respect? As Christians,
we recognise God as a purposeful being; therefore if we are made in His image, we
will also be purposeful beings. It is natural for us to ask Why? questions.
But Dawkins just rides past the implication. No doubt if pressed, someone will dream
up some selective or adaptive advantage for this trait. But this, as usual, would
only be hindsight, based on the assumption of an evolutionary world view. There
would be no data to back it up.
The point does lead him, however, to an interesting conclusion about Why?
questions. He says some of them are simply inappropriate and not worth asking, much
less answering. But in discussing our temptation to always ask these why questions,
Dawkins states on page 96,
And the same temptation is often positively relished when the topic is the origin
of all things or the fundamental laws of physics, culminating in the vacuous existential
question ‘Why is there something rather than nothing?’
This fundamental philosophical question is vacuous to someone like Dawkins simply
because he has no answer for it within his world view. He knows this will be very
unsatisfying for most people, so he simply seeks to evade the question by declaring
it out of bounds. He completes his condescension on page 98 when he says,
Before Darwin, even educated people who had abandoned ‘why’ questions
for rocks, streams and eclipses still implicitly accepted the ‘why’
question where living creatures were concerned. [Presumably because Dawkins admits
on the previous page that living things ‘seem to have purpose written
all over them.’] Now only the scientifically illiterate do.
Arrogance and condescension is the only answer that Dawkins can offer.
In the next paragraph, however, Dawkins admits that evolutionary biologists do ask
‘Why’ questions, like ‘Why do birds sing?’, but
only in a special metaphorical sense. The assumption of design is only used as a
working tool. Organisms expend so much energy on complex structures that selection
must have crafted them for some ‘purpose’. It would be too big of a
waste of energy otherwise.
Dawkins then introduces the concepts of reverse engineering and utility function.
Reverse engineering means deducing the purpose of some unknown object that at least
appears to be designed. In living things this means complex structures. Utility
function refers to the thing which the engineering is attempting to preserve or
enhance. According to Dawkins the universal utility function is the maximising of
DNA into the next generation. ‘Why are forest trees so tall? Simply to overtop
rival trees.’ Those that succeed maximise their DNA replication.
A mad race ensues for the tallest trees that may seem rather wasteful.
It is ludicrous and wasteful only from the point of view of a rational economic
planner thinking in terms of maximizing efficiency. But it all makes sense once
you understand the true utility function — genes are maximizing their own
survival.
Dawkins’ point can only be made by anthropomorphising DNA as if it is intentionally
maximising its survival. Of course such is not the case; it only looks that way.
There is only an ‘illusion’ of intentionality. With all these illusions
one cannot help but at least expect that, at the very least, there is an illusionist
behind it all.
At the chapter’s end Dawkins returns to his initial topic.
So long as DNA is passed on, it does not matter who or what gets hurt in the process
. . . . But Nature is neither kind nor unkind . . . . Nature is not interested one
way or another in suffering, unless it affects the survival of DNA.
He even admits that this is not a recipe for happiness. The problem of evil returns.
Dawkins’ simple answer is that there is no problem of evil. Nature just
is. He recounts a story from the British papers of a school bus crash
with numerous fatalities and reports a Catholic priest’s inadequate response
to the inevitable ‘Why’ question. The priest indicates that we really
don’t know why God would allow such things, but that these events at least
confirm that we live in a world of real values: real positive and negative. ‘If
the universe were just electrons, there would be no problem of evil or suffering.’
Dawkins retorts that meaningless tragedies like this are just what we expect from
a universe of just electrons and selfish genes along with equally meaningless
good fortune.
However, it is also what we expect in a fallen world. Evolutionary writers never
recognise this clear biblical theme. This is not the way God intended His world
to be. What is unexpected in an evolutionary world are people shaped by uncaring
natural selection who care about evil and suffering at all. Why are we not as indifferent
as natural selection? In making his point, Dawkins says that the amount of suffering
in the natural world is beyond all ‘decent’ contemplation. Where does
decency come from? He calls the bus crash a ‘terrible’ story. Why is
this so terrible if it is truly meaningless? How can we be such a ‘purpose-ridden
species’? Clearly, Dawkins cannot live within the boundaries of his own world
view. We see purpose and fret over suffering and evil, because we are created in
the image of a God who has the same characteristics. There are aspects of our humanity
that are not explainable by mutation and natural selection. Dawkins must try to
explain it, however, because his naturalistic world view leaves him no choice.
Unexplained Thresholds
Dawkins closes his book with a final chapter on the origin of life and discussion
on the possibilities of life elsewhere in the universe. This chapter is a bit of
a disappointment because there is really very little to say. To be sure, it is filled
with the usual Dawkins arrogance and leaps of naturalistic logic, but there is no
real conclusion — just the possibility of contacting whatever other life may
be out there.
Dawkins begins with a definition of life as a replication bomb. Just as some stars
eventually explode in supernovas, so some planets explode with information in the
form of life —life that may eventually send radio messages or actual life
forms out into space. Dawkins admits that ours is the only example of a replication
bomb we know, so it is difficult to generalise as to the overall sequence of events
that must follow from when life first appears to the sending of information out
into space, but he does it anyway.
While we can clearly distinguish between random and intelligent radio messages,
Dawkins is unable to even ask the question about the origin of the information-rich
DNA code. I suppose his answer is contained on page 138 when he says,
We do not know exactly what the original critical event, the initiation of self-replication,
looked like, but we can infer what kind of an event it must have been. It began
as a chemical event.
This inference is drawn not from chemical, geological, or biological data. Dawkins
takes a few pages to evoke wonder from the reader by documenting the difficult barriers
that had to be crossed. It is rather an implication that is derived from his naturalistic
world view. It is a chemical event because that is all that is allowed. While it
may be difficult, we are assured that it happened!
The book closes with a discussion of the Ten Thresholds that must be crossed for
a civilisation of our type to exist. Along the way, Dawkins continues to over-reach
the evidence and make assumptions based on naturalism without the slightest thought
that his scenario may be false or at least very wide of the mark.
The first threshold is the origin of life, some kind of self-replicating system.
Threshold 2 is the Phenotype Threshold. Beyond replication, there must be some system
for the ‘genotype’ to express a ‘phenotype’ or protein.
Clam shells do not give rise to other shells. Shells are made by DNA, and DNA makes
DNA. This is a crucial and difficult step for chemical evolution. But Dawkins gives
no clues, because there are no clues as to how proteins came to be made from RNA,
and RNA from DNA.
Threshold 3 is the Phenotype Team Threshold. Genes do not work in isolation. They
work together. Everything affects everything else. Again, there are no real clues
as to how this important jump in complexity was to be achieved. Threshold 4 is The
Many-Cells Threshold. To continue to build complexity, not only must genes work
together, but ultimately, cells must learn to work together. This achievement must
be followed by a distribution of the tasks of living among different specialised
cells or tissues. But how this occurs is not addressed.
Threshold 5 is the High-Speed Information-Processing Threshold or the Nervous System
Threshold. There must be communication between the different cells and tissues.
Threshold 6 is the Consciousness Threshold. The Language Threshold is step number
7 and is probably linked to Threshold 6. Threshold 8 is crossed with an explosion
of culture and technology, the Co-operative Technology Threshold. From this erupts
the Radio Threshold, Threshold 9. The culmination is the Space Travel Threshold,
Threshold 10. All along the way Dawkins tries to amaze us with both the necessity
and complexity of each threshold but fails miserably to explain how each jump is
to be accomplished. He depends totally on the explanatory power of natural selection
to accomplish whatever transition is needed. It is just a matter of time.
Conclusion
But of course, this begs the question. Dawkins perfects this art for 161 pages.
Despite the smoke and mirrors, Richard Dawkins is still trying to sail upstream
without a paddle. It just won’t work. While many of his explanations and ruminations
should make careful reading for creationists (he is not stupid and writes well),
I have tried to point out a few of his inconsistencies, assumptions, and poor logic.
What bothers me most is that this is meant to be a popular book. His wit and dogmatism
will convince and influence many. For these reasons I found it a frustrating and
sometimes maddening book to read. Unfortunately, few will think their way through
these pages and will be asking few if any questions of the author along the way.
This is where the real danger lies. We must not only show others where he is wrong,
but help them how to discover these errors on their own. We must help people to
think, not just react.
References
- Behe, M. J., 1990. Histone deletion mutants challenge the molecular
clock hypothesis. Trends in Biochemical Science, 15:374–376.
Return to text.
- Lewis, C. S., 1947. Miracles: A Preliminary Study, Macmillan
Publishing Co., Inc., New York, p. 22. Return to text.
- Marshall, G., 1996. An eye for creation. Creation Ex Nihilo,
18(4):20–21. Return to text.
- ReMine, W. J., 1993. The Biotic Message: Evolution Versus Message
Theory, Saint Paul Science, Saint Paul, Minnesota. Chapter 8 shows in mathematical
detail that natural selection could result in only 1667 gene substitutions in 500,000
generations given the most optimistic assumptions. Return to text.
- Moreland, J. P. (ed.), 1994. The Creation Hypothesis: Scientific
Evidence for an Intelligent Designer, InterVarsity Press, Downers Grove, Illinois.
Return to text.
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