Richard Dawkins' book Climbing Mount Improbable is a book trying to persuade
you that blind Darwinian evolution (evolution caused by natural
selection and random mutations) produced pretty much all the
biological complexity we see in the world. The book is centered
around a mountain-climbing analogy. In this analogy, reaching some
height of biological complexity is portrayed as something like
climbing a mountain. The book assures us that Darwinian evolution
is able to climb “even the most precipitous heights” because it
takes the “mildly sloping paths” rather than the hardest steepest
path up the mountain. These paths Dawkins describes (on page 73) as
“gently inclined grassy meadows, graded steadily and easily towards
the distant uplands.” He tells us on page 77 that Darwinian
evolution works by “going round the back of Mount Improbable and
crawling up the gentle slopes.”
This is a very poor
analogy – an inappropriate metaphor. The appearance of a
new type of macroscopic organism involves all kinds of complex parts appearing on
the scene in an incredibly intricate and coordinated way, so that
great functional coherence is achieved. But climbing a mountain does
not involve any type of event in which complex parts are assembled.
Climbing a mountain doesn't even involve complexity. So mountain
climbing is a terrible analogy for achieving some stunning wonder of
coordinated biological complexity.
We can imagine all
type of analogies that would have been more appropriate for
describing blind processes producing complex biological structures.
One such analogy would be the idea of trees in a forest luckily
forming into a log cabin, or stones randomly forming into a stone
house. But such analogies would throw unwanted light on the
difficulties of random processes forming coherent structures. So
rather than using such an analogy, Dawkins has chosen an
inappropriate analogy that seems to have been chosen purely for its
rhetorical advantages.
In this sense he's
followed in the same steps as Darwin, who gave us the inappropriate
metaphor of “natural selection,” a term suggesting incorrectly
that nature chooses things. The metaphor is not literally accurate,
because strictly speaking only conscious agents choose things. The
idea of survival of the fittest can be stated without a metaphor by
using either the term “survival of the fittest” or “differential
reproduction.” So why did Darwin make such use of the metaphorical
term “natural selection”? Probably for the same reason
Dawkins has chosen a mountain-climbing analogy: for rhetorical
advantage. Once a person has been persuaded that the evolution of
incredibly complex machine-like functionality is like
mountain-climbing, the same person might be persuaded that such an
end was easily achieved by “walking up the easy back route,”
because there are often “easy back routes” leading to mountain
tops. But since mountain-climbing doesn't involve even the simplest
combination of parts, you are deluding yourself if you think that
this mountain-climbing analogy is suitable for describing the
appearance of wonderfully coordinated biological machinery.
On page 77 of the
book, Dawkins tries to suggest that Darwinism is not a theory of
chance. He says, “It is grindingly, creakingly, crashingly obvious
that if Darwinism were really a theory of chance, it couldn't work.”
But, of course, Darwinism is a theory of chance, the claim
that the combination of blind chance mutations and natural selection
is enough to produce the origin of new species. As Dawkins says on
page 80, “One stage in the Darwinian process is indeed a chance
process – mutation.” So on one page he talks as if Darwinism
isn't a theory of chance, and a few pages later he's talking as if it is just that.
Dawkins admits on page 81 that
mutations usually have bad effects, not good effects. That is a
severe understatement, and a more candid statement would have been to
say that for every mutation that is helpful, there are hundreds or
thousands that are harmful.
On page 96 Dawkins
tries to suggest the idea of macromutations, that a single mutation
can cause a huge change in an organism. He asks, most ridiculously,
“Couldn't the elephant's trunk have shot out in a single, giant
step?” We know why he wants to suggest this old “hopeful
monsters” idea. If macromutations can occur, then rather than have
to believe that lots of favorable mutations were needed for some
biological innovation (something incredibly unlikely to occur by
chance), we can believe that in some cases a favorable innovation
arose from a single macromutation.
But the evidence
Dawkins gives in support of the idea of macromutations is rather
laughable. He states this on page 96:
Macro-mutations
do happen. Offspring are sometimes born radically, monstrously
different from either parent, and other members of the species. The
toad in figure 3.2 is said by the photographer, Scott Gardner of the
Hamilton Spectator, to
have been found by two girls in their garden in Hamilton, Ontario. He
says that they put it on the kitchen table for him to photograph. It
had no eyes at all on the outside of its head. When it opened its
mouth, Mr. Gardner said, it seemed to become more aware of its
surroundings.
This is laughable as
evidence. The photo he shows is a mutant frog that apparently has no
eyes. Inside the frog's mouth are two little round things that could
be anything – maybe eyes, or maybe something the frog ate, or maybe
two marbles the two girls put in the frog's mouth. The second-hand
claim that the frog “seemed to become more aware of its
surroundings” when it opened its mouth is laughable from an
evidence standpoint. There are, in fact, no known cases of a
proven macromutation that ever produced a useful new feature (visible to the eye) in a
biological organism. Dawkins' frog anecdote smacks of desperation.
Why he is citing some story in the Hamilton Spectator rather than
citing a scientific journal? Darwinist biologist Jerry Coyne
says this about macromutations:
Macromutationism
is the idea that important evolutionary changes between groups were
produced by single mutations with very large effects....The
notion of macromutationism pops up every few years in evolutionary
biology. It’s wrong but it’s resilient.
Two scientists have
noted, “In fact, to our knowledge, no macromutations ...
that gave birth to novel proteins have yet been identified.”
Referring to the
fossil record, on page 106 Dawkins makes the damaging admission that
“Transitional forms are generally lacking at the species level.”
Why should there not be a vast abundance of transitional forms in the
fossil record if Darwinian theory is correct?
One of the great
difficulties in natural history is explaining the origin of flight,
where we have the wing-stump problem. For flight to have appeared, a
transitional species would presumably have to have had a mere wing
stump. But wing stumps are not at all useful, so we cannot explain
the appearance of such a thing by saying that it provided some
survival benefit.
On page 115 Dawkins starts
trying to defend the idea that there is an “easy back path” by
which Darwinian evolution could produce flying species. He says, “One possibility is that true flight grew out of the habit of gliding
between trees, which lots of animals do, even if they don't quite
fly.” On page 118 he suggests that it would have been easy for
gliding to evolve:
In
none of these cases is there any difficulty in finding a gentle path
up Mount Improbable. Indeed, the fact that the gliding habit has
evolved so many times testifies to the ease with which these mountain
paths can be found.
This type of
reasoning is very common among orthodox Darwinists, but it is
fallacious. The reasoning goes like this: it must be easy for blind
evolution to produce Capability X, because Capability X has appeared
numerous times in nature. Such reasoning is fallacious because we
have no way of knowing how many occurrences were produced by a
particular type of process that originated biological complexity.
Consider these possibilities:
Possibility 1:
Species have originated merely through natural selection and random
mutations.
Possibility 2:
Species have originated through the action of some mysterious cosmic
life-force or cosmic programming that acts throughout the universe as
an organizational principle.
Possibility 3:
Species have originated because extraterrestrial spaceships have
periodically arrived and planted new life forms on our planets.
Possibility 4:
Species originate when new types of life stray into our planet after
spacetime wormholes open up leading from some other dimension to our
planet.
Possibility 5:
Species originate because some divine creator or angel causes them to
appear.
Possibility 6:
We are living in a computer simulation created by extraterrestrials, and all fossils found are simply details added by them as kind of "backstory details" to flesh out the simulation.
Since we don't know
which of these is true, we cannot appeal to the fact that some
feature exists in multiple life forms as something that helps to
substantiate any of these claims; because such a thing might happen
under any one of these scenarios. In the case of gliding, we have no
known cases of gliding that have been proven to have been produced by
natural selection and random mutations. So the mere fact that gliding
has appeared in multiple species does nothing to support the claim
that gliding could have easily appeared by natural selection and
random mutations.
There are, in fact,
very strong reasons for believing that a feature such as gliding
could not have appeared through natural selection and random
mutations. Let us consider the nature of gliding. Gliding between
trees or branches requires an incredibly precise coordination between
muscles, bones, web-like structures between limbs, eyes, and brain –
for animals must not only land on a distant tree branch, but also be
able to land on the branch without falling. If that coordination
isn't just right, it will be very harmful or suicidal for an animal
to try to glide between trees; for the animal will fall to the
ground. Developing gliding is similar to developing a suspension
bridge, in the sense that until the functionality is almost
completed, what you have is functionality that will be suicidal if
you try to use it. The table below illustrates the point.
Gliding | Suspension Bridge | |
25% Completion | Suicidal (jumping causes animal to fall to death) | Suicidal (car using bridge ends up in river) |
50% Completion | Suicidal (jumping causes animal to fall to death) | Suicidal (car using bridge ends up in river) |
75% Completion | Suicidal (jumping causes animal to fall to death) | Suicidal (car using bridge ends up in river) |
100% Completion | Marginally beneficial, or maybe not – still great risks in gliding, and sparse benefits | Beneficial (car is able to cross bridge) |
So it seems that the
appearance of gliding cannot be explained using Darwinian ideas. We
have no explanation of how a species would have evolved the first 10%
or the first 20% of gliding functionality, which would have had no
“survival of the fittest” benefit. It's the same type
of problem involved in trying to explain the evolution of flying
without imagining gliding, which gives us problems such as the fact
that there would be no survival benefit if just a wing stump ever
appeared.
Then there's also
the fact that if one imagines gliding animals turning into flying
animals, you have no explanation of how all the changes occurred
needed to change from gliding animals to flying animals. Trying to
explain how Darwinian evolution could have produced “the
development of gliding” plus also “the evolution from gliding to
flying” is not easier than trying to explain how Darwinian
evolution could have produced only the evolution of flying.
For the reasons
giving above, trying to make the evolution of birds seem easy by
suggesting that nature first evolved gliding animals and then evolved
birds from such animals is like reasoning that it's not very hard to
climb to the top of the Met Life skyscraper in midtown Manhattan
using outer wall climbing, because you can first climb the outer
walls of the Chrysler building and then jump to the top of the nearby
Met Life skyscraper. Alternate theories discussed by Dawkins to
account for the origin of flight are not any more credible, and we
can chuckle at his suggestion that perhaps feathers were first
developed to catch insects. Dawkins has no clear story to tell us,
saying that “perhaps birds began flying by leaping off the ground,
while bats began by gliding out of trees” while adding that
alternately “perhaps birds too began by gliding out of trees”
(page 126). Such uncertainty does not amount to a convincing story
of how flight appeared in birds.
In Chapter 8 Dawkins
begins trying to explain how vision could have evolved through random
mutations and natural selection. He uses the “smoke and mirrors”
trick followed by similar reasoners, by focusing on the eye and
acting as if we merely need to explain the appearance of eyes to
explain the appearance of vision. Proceeding in such a way is very
fallacious, because the eye is merely one part of a complicated
system needed to explain vision, what we may call the vision system.
The main elements of the vision system are:
- The eye, which in modern organisms is an intricate arrangement of parts
- Extremely complicated proteins and biochemistry used by the eye to capture light
- The optic nerve connecting the eye to the brain
- Extremely complicated changes in the brain needed for an organism to make use of inputs from the eye.
These parts are so
complicated that even the most primitive vision system providing a
minimal benefit will require an extremely complicated invention
exceedingly unlikely to appear by chance, as unlikely as falling
trees forming into a nice roofed log cabin. You cannot explain such
an invention merely by describing how a primitive eye could appear.
To try to explain
how a primitive eye could appear, Dawkins appeals to a scientific
paper published by Nilsson and Pelger, and Dawkins inaccurately
describes this as a “computer model.” The paper does not actually
describe any computer model or computer simulation. The paper
describes how a circular patch of light-sensitive cells could change
into a curved cupped eye, conveniently assuming that it underwent
exactly the changes that would bring about such a thing (which would
be most unlikely to occur given the thousands of possible ways that
random mutations might change the appearance of such a flat circular
patch). The paper cheats by assuming that such a flat circular patch
of light-sensitive cells would come to exist before it had any
usefulness. The paper also includes absurd statements such as “The
evolution of an eye can thus be compared to the lengthening of a
structure, say a finger, from a modest 8 cm to 8000 km, of a fifth of
the Earth's circumference.” That is wrong because the evolution of
an eye would be the assembly of a very intricate arrangement of
coordinated parts, something vastly more complicated than just a mere
lengthening of an object.
I can describe the
type of smoke-and-mirrors trick involved in Nilsson and Pelger's
paper. It works like this: given some complex functional arrangement
of parts that is incredibly hard to achieve by chance, you try to
make it look easy by ignoring 45% of the arrangement, and also
assuming that another 45% of the arrangement was conveniently there
to begin with; and then you argue that it's easy to make the
arrangement because it's not too hard to make the remaining 10%. So,
for example, someone might argue that it's pretty easy to make a
suspension bridge, by ignoring the whole superstructure (the towers
and the steel cables), and just assuming that the huge complicated
substructure (leading down into the river) just happens to
conveniently exist, and then kind of talking as if making a
suspension bridge is as easy as building a road.
This is very close
to what Nilsson and Pilger have done. They've simply ignored the
requirements of an optic nerve and the incredibly complicated brain
changes needed for vision, and they've assumed that the
light-sensitive cells (so hard to achieve because they require
fantastically improbable and intricate light-capturing proteins) were
just there to begin with. Having either ignored or assumed the prior
existence of 90% of a vision system, they then argue that the
remaining part is easy, so it's easy for animals to get vision. This
is a huge fallacy which Dawkins repeats, because he's so very eager
to believe that vision is an easy hurdle for evolution to jump over.
Ignoring the almost
unfathomable intricacy of a vision system, Dawkins seems to think
that explaining eyes is as easy as explaining how some cells might
simply form into a cup-shaped curve. Similarly, a person might
fallaciously claim that it's real easy to make a camera, because all
you need is a little box shape – or that it's easy to make a moon
rocket, because all you need is a big tube shape.
Here is a
description of the insanely complicated light-capturing biochemistry
going on in the eye, from a biochemistry textbook:
- Light-absorption converts 11-cis retinal to all-trans-retinal, activating rhodopsin.
- Activated rhodopsin catalyzes replacement of GDP by GTP on transducin (T), which then disassociates into Ta-GTP and Tby.
- Ta-GTP activates cGMP phosphodiesterase (PDE) by binding and removing its inhibitory subunit (I).
- Active PDE reduces [cGMP] to below the level needed to keep cation channels open.
- Cation channels close, preventing influx of Na+ and Ca2+; membrane is hyperpolarized. This signal passes to the brain.
- Continued efflux of Ca2+ through the Na+-Ca2+ exchanger reduces cytosolic [Ca2+].
- Reduction of [CA2+] activates guanylyl cyclase (CG) and inhibits PDE; [cGMP] rises toward “dark” level, reopening cation channels and returning Vm to prestimulus level.
- Rhodopsin kinase (RK) phosphorylates “bleached” rhodopsin; low [Ca2+] and recoverin (Recov) stimulate this reaction. Arrestin (Arr) binds phosphorylated carboxyl terminus, reactivating rhodopsin.
- Slowly, arrestin dissociates, rhodopsin is dephosphorylated, and all-trans-retinal is replaced with 11-cis-retinal. Rhodopsin is ready for another phototransduction cycle.
We have no mention
of any of these complexities in Dawkins' book, which show the
absurdity of his claims that it's easy to get an eye. The text above
mentions proteins that are far more structurally complicated than a
primitive eye, such as a rhodopsin protein specified in a gene that uses 1000+ base pairs to specify the protein.
Rhodopsin proteins used in vision
With a vision system
we have the same type of “uselessness of a wing stump” problem in
explaining the origin of flight. Aquatic animals are believed to be
the first that had eyes. But imagine an aquatic animal with only the
poorest type of vision, the type of vision you have if you cover your
eyes with 2-ply toilet paper. With such vision the aquatic animal
couldn't tell if other aquatic animals are far away, but it could
only tell if they are very close (seeing just a very blurry blob
ahead of itself). But a blind aquatic animal could already tell when
another aquatic animal is very close, from its splash (and in a sea
of blind fish, if you're a blind fish you will have other fish
frequently bumping into you). So if a blind aquatic animal in a sea
of blind aquatic animals gets the weakest type of vision, some
extremely blurry vision, it doesn't produce a benefit. Very weak
vision might also allow an aquatic animal to know which way was up in
the water. But a blind aquatic animal could already tell that from
temperature changes in water and pressure changes (the deeper you go,
the colder it is and the greater the pressure). And an aquatic animal
doesn't need to know which way is up in the water.
So the poorest type
of vision would have no survival value for an aquatic animal. If
there were to be some incredibly improbable set of random mutations
allowing the poorest type of vision, that would not be rewarded. For
an aquatic animal, there is no series of gradual changes, each
rewarded, that leads to the advanced functionality of vision. There
is instead a high functionality threshold that must be reached before
any survival reward is obtained, involving a complex, highly
coordinated arrangement of parts needed to get something better than
the weakest type of vision. We cannot explain how such a high
threshold could be reached through random mutations and natural
selection. For the threshold to be reached, too many complex parts
have to be assembled with too much coordination. Far from being an
“easy back route,” this is a high cliff like the front face of
Half Dome in Yosemite.
Natural selection is
merely a dumb filter, something that can filter out bad designs but
cannot explain the appearance of good designs. There is a very
general reason why random mutations plus natural selection (a
survival reward for greater fitness) cannot explain the origin of
complex biological functionality. The reason is that the early
stages of bringing into place such functionality would in general not
yield rewards. Fragmentary implementations yield only very poor
rewards or no rewards at all, and it is usually true that no reward
is produced until a large fraction of an implementation is produced.
So in almost all cases it is not possible to describe a pathway by
which a series of random gradual changes could yield very complex
functionality, with the early parts of the pathway producing a
significant reward. If there is no reward in the early parts of the
implementation pathway, it is gigantically improbable that nature
would walk down that pathway, which would be only one of quadrillions
of possible random paths.
The diagram below
illustrates this point. The part in red represents the initial
stages of a biological innovation, stages that are pre-functional and
therefore not explained by an appeal to natural selection, which can
only come into play once a functional threshold has been reached.
Dawkins tells us
that eyes independently evolved 44 times, and scientists say that
random mutations would have to occur 100 times for a particular
biological innovation to become fixed in the gene pool. This means
our orthodox Darwinist is required to believe that 4400 times blind
chance produced a vision system, which is rather like believing that
4400 full water-tight log cabins have been produced by random falling
trees in forests (although the latter is far more likely). Given the
intricacy of a vision system, vastly greater than a log cabin, we
would not expect a vision system to have arisen by chance mutations
and natural selection even once in the history of our galaxy. So when
Dawkins tells us that an eye can appear on the evolutionary scene “at
the drop of a hat,” your fairy tale alarm should start ringing
very loudly.
Considering
all of its required parts (including very complex brain changes,
fine-tuned proteins, an optic nerve, and intricate eye anatomy), a
vision system is one of the most complex cases of organized
functionality known to man. Adherents of the Darwinian “modern
synthesis” have no way to account for this, for they lack any
theory of organization. Darwinism is a theory of accumulation,
not a theory of organization – the accumulation of random changes
by mutations. As an evolutionary biologist confessed recently,
“Indeed, the MS
[modern synthesis] theory lacks a theory of organization that can
account for the characteristic features of phenotypic evolution, such
as novelty, modularity, homology, homoplasy or the
origin of lineage-defining body plans.” But what do some people do
when they have to explain mountainous levels of organization, and
they lack a biological theory of organization? They try to fake
their way through, by using verbal tricks, carefully selective prose
and omissions to try to make the mountain of organization look like a
mere molehill of organization.
We may compare
Darwinian evolution to a man trying to build elaborate structures,
but who is acting under two handicaps. The first is that he has a
refrigerator-sized steel block chained to his leg. The block (causing
such slowness) symbolizes the fact that Darwinian evolution relies on
favorable random mutations to achieve innovations, but such mutations should be so rare that
waiting for them means the Darwinian evolution of complex macroscopic innovations should work no faster than
a snail's pace. We may also imagine that this man has been commanded to operate under a rule of “do 100 harmful things for every useful
thing you do.” Such a rule symbolizes the fact that for every
random mutation that is helpful, there are very many that are
harmful. How fast should such a man be able to build useful
structures? Never faster than an insanely slow pace. So if the fossil
record shows something like the Cambrian Explosion, in which every
major phylum of animal now existing appeared in a relatively short
time, we must suspect something was going on much more than just
Darwinian evolution by random mutations and natural selection.
Any convincing
naturalistic attempt to explain the origin of vision and the origin
of other complex biological functionality would devote a great deal
of time to explaining the exceptionally fine-tuned and intricate
biochemistry of life, and would also devote a great deal of time to
explaining how it is that so many fine-tuned proteins came to arise
in human biology. For countless proteins there is what is called a
steep fitness landscape. This means that the proteins can only
function well if they have a small number of states very similar to
their existing states. Explaining the origin of such proteins is a
nightmare for thinkers such as Dawkins who maintain that nothing but
blind chance and natural selection brought these proteins into
existence. Calculations repeatedly indicate that it would take
something like ten to the seventieth power tries or search attempts
for nature to find a particular type of protein known to exist; and
there are thousands of such proteins in the human body. The number
of search attempts that nature would have time to accomplish in the
history of the earth is some number trillions of times smaller.
Does Dawkins book
have some chapters trying to explain the origin of fine-tuned
proteins? To the contrary, there isn't even an entry for proteins in
the index of his book, nor is there an entry for chemistry or
biochemistry. We would also expect that any convincing naturalistic
attempt to explain the origin of vision and the origin of other
complex biological functionality would devote a great deal of time to
topics such as coordination and coherence, since the marvel of
biological functionality is largely the wonder of how lots of small
parts can work together in such a coordinated and coherent way. But
we find no entry for “coordination” or “coherence” in
Dawkins' index, which also doesn't have an entry for “complexity.”
Dawkins book fails
completely in its attempts to show “easy back routes” by which
Darwinian evolution could produce great wonders of complexity. He
fails to provide a single example of some impressive piece of
macroscopic biological functionality that has been proven to have
been produced by natural selection and random mutations. No such
example exists. Dawkins also fails to provide a single plausible
story leading us to think that natural selection and random mutations
would have been capable of producing any impressive piece of very
complex macroscopic biological functionality.
In this regard
Dawkins is in good company. The passage on vision biochemistry that I
quoted is from page 459 of the 1119-page biochemistry textbook
Lehninger Principles of Biochemistry. The book gives us a
thousand pages of description of the most intricate machine-like
biochemistry in the human body, but does basically nothing to explain
how this functionality could have originated (apart from a short
pro-forma review of Darwinism tenets, which don't specifically deal
with biochemistry). There is endless discussion of proteins, but
when I look up “proteins, evolution of” in the index of the book,
I am referred to 5 pages that make no substantive clarification as to
how fine-tuned proteins could have naturally evolved. How did we get
all these thousands of fine-tuned proteins, each so fantastically
unlikely to have arisen by chance? Our 1119-page biochemistry
textbook has no real answer. Similarly, the 1041-page textbook
Biochemisty by Lubert Stryer of Stanford University is notable
for making no substantive attempt to explain the origin of any part of the
wonderful biochemical machinery it discusses. The index of the book
lists only 20 pages referring to evolution, and when I look up those
pages I find only passing or incidental references to evolution.
Mentioning Darwin in only one paragraph, with only a passing mention,
the 1041-page book lacks even a substantial exposition of Darwinian
theory, and doesn't even mention natural selection in its index, ignoring the topic of the origin of life and the origin of
proteins. Which is not what we would expect if Darwinian theory were
useful in explaining the origin of life or very complex biochemistry
machinery.
Nor is there any
real origins answer offered by this long recent review of the topic
of protein evolution, which states this near its end (referring to
protein folds):
It is not clear
how natural selection can operate in the origin of folds or active
site architecture. It is equally unclear how either micromutations or
macromutations could repeatedly and reliably lead to large
evolutionary transitions. What remains is a deep, tantalizing,
perhaps immovable mystery.
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