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Authors: Arthur Koestler

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countless ways
of adapting to one and the same environment
, and some of these ways
are so incredibly tortuous and complicated that the term 'adaptation'
becomes empty of meaning. Consider this example from Sir Alister Hardy's
The Living Stream
:

 

There are some kinds of orchids with flowers which mimic, in colour,
shape and smell, the female form of certain insects and so offer
sexual attraction to the males of these insect species; the excited
spouses who come for the creative act, unwittingly, by carrying
pollen, complete, instead, the sexual process for the flower! [18]

 

Or, to quote von Bertalanffy yet again:

 

I for one . . . am still at a loss to understand why it is of
selective advantage for the eels of Comacchio to travel perilously to
the Sargasso sea, or why Ascaris has to migrate all around the
host's body instead of comfortably settling in the intestine where
it belongs; or what was the survival value of a multiple stomach
for a cow when a horse, also vegetarian and of comparable size,
does very well with a single stomach. [19]

 

And how does 'adaptation' explain the fantastic transformations of the
caterpillar into a chrysalis -- spinning itself into a cocoon, where
it undergoes a complete transformation which involves the dissolution
of the larval organs and tissues and their complete re-moulding into a
winged adult? Books on natural history have innumerable examples of such
far-fetched ways of 'making a living' as a species, but they are rarely
mentioned in theoretical works on evolution, because they reveal too
glaringly that the theory begs the vital questions. Thus 'adaptation',
as a
deus ex machina
of 'natural selection', shares the fate of its
precursors, 'survival of the fittest' and 'differential reproduction.

 

 

 

3

 

 

According to the neo-Darwinian doctrine, the raw material on which the
magic of natural selection operates is provided by random mutations, i.e.,
chemical changes in the genes, the carriers of heredity. These changes
are triggered by radiations, noxious chemicals or excessive heat, and
are 'random' in the sense of being completely unrelated to the animal's
needs or welfare, or its natural environment: they are in the nature of
accidents which interfere with the normal functioning of the delicately
balanced organism. Accordingly, the vast majority of mutations have either
damaging or trivial effects; but from time to time, so the theory goes,
there is a lucky hit, which will be preserved by natural selection,
because it happens to confer some small advantage on the bearer of the
mutated gene; and given sufficient time, 'anything at all will turn up',
as Sir Julian Huxley wrote. 'The hoary objection of the improbability
of an eye or a hand or a brain being evolved by "blind chance" has lost
its force' -- because 'natural selection operating over stretches of
geological time'
[20]
explains everything.

 

 

Compare this statement with the following by Waddington:

 

To suppose that the evolution of the wonderfully adapted biological
mechanisms has depended only on a selection out of a haphazard set
of variations, each produced by blind chance, is like suggesting
that if we went on throwing bricks together into heaps, we should
eventually be able to choose ourselves the most desirable house. [21]

 

Nevertheless, Jacques Monod (Nobel Prize, 1965) calls evolution a
'gigantic lottery'
[22]
or 'nature's roulette'
[23]
and concludes:

 

Chance alone is at the source of every innovation, of all creation
in the biosphere. Pure chance, absolutely free but blind, at the
very root of the stupendous edifice of evolution: this central
concept of modern biology is no longer one among other conceivable
hypotheses. It is today the sole conceivable hypothesis, the
only one that squares with observed and tested fact. And nothing
warrants the supposition -- or the hope -- that on this score our
position is likely ever to be revised . . . [24]
The universe was not pregnant with life nor the biosphere with man.
Our number came up in the Monte Carlo game. [25]

 

But the roulette analogy hides rather than indicates the fantastic
improbability of any major evolutionary advance produced by chance mutations.
For such an event to occur, it is not enough that a certain required number,
say the 17, should come up on the roulette table -- but that it should
come up simultaneously on a dozen or so tables in the same establishment,
followed by the 18, 19 and 20 simultaneously on all tables.

 

 

Let me illustrate this by a few examples. The first is very simple and
trivial, involving only four roulette wheels. The giant panda has on
its front limbs an added, sixth finger. This could be a typical case of
a deformation caused by a deleterious chance mutation; it happens to be
quite useful to the panda in manipulating bamboo shoots, but it would of
course be a useless hindrance if it were not equipped with the requisite
muscles, nerves and blood-supply. The chances that among all possible
genetic mutations just those which produced the added bones,
nerves, muscles and arteries occurred
simultaneously
and
independently
from each other are infinitesimally small. And yet
in this case we have only four main factors -- four roulette wheels at
work. When it comes to such composite marvels as the vertebrate eye --
that classic stumbling block of the Darwinian theory -- with its retina,
rods and cones, lens, iris, pupil and what have you, the odds against the
harmonious evolution of its components by independent random mutations,
i.e., by 'blind chance', becomes,
pace
Huxley, absurd. Darwin himself
clearly realized this when, in 1860, he wrote to Asa Gray: 'I remember
well the time when the thought of the eye made me cold all over.'
[26]
It still has that effect on the upholders of the doctrine,
so they avoid discussing it, or resort to elaborate evasions.*

 

* For a summary of the problems posed by the evolution of the eye see,
e.g. Grassé (1973). pp. 176-81 and Wolsky (1976), pp. 106 f.

 

Equally chilling is the idea that some ancestral reptiles became transformed
into birds by the small, step-by-step changes caused by random mutations
affecting different organs. In fact one gets goose-pimples at the mere
thought of the number of Monod's roulette wheels which must be kept spinning
to produce the simultaneous transformation of scales into feathers,
solid bones into hollow tubes, the outgrowth of air sacs into various
parts of the body, the development of the shoulder muscles and bones
to athletic proportions, and so forth. And this re-casting of bodily
structure is accompanied by basic changes in the internal systems,
including excretion. Birds never spend a penny. Instead of diluting their
nitrogenous waste in water, which is a heavy ballast, they excrete it
from the kidneys in a semi-solid state though the cloaca. Then there
is also the little matter of the transition, by 'blind chance', from
the cold-blooded to the warm-blooded condition. There is no end to the
specifications which have to be met to make our reptile airborne or to
construct a camera eye out of living software.

 

 

To conclude this section, here is a less dramatic example of an evolutionary
advance -- the seemingly modest step which led to the transformation of
the amphibian egg into the reptilian egg. I have described this process
in
The Ghost in the Machine
, and am quoting it again, because its
explanation by the Darwinian schema is not only vastly improbable,
but logically impossible.

 

The vertebrates' conquest of dry land started with the evolution
of reptiles from some primitive amphibian form. The amphibians
reproduced in the water, and their young were aquatic. The decisive
novelty of the reptiles was that, unlike amphibians, they laid their
eggs on dry land; they no longer depended on the water and were free
to roam over the continents. But the unborn reptile inside the egg
still needed an aquatic environment: it had to have water or else
it would dry up at an early stage. It also needed a lot of food:
amphibians hatch as larvae who fend for themselves, whereas reptiles
hatch fully developed. So the reptilian egg had to be provided with
a large mass of yolk for food, and also with albumen -- the white
of egg -- to provide the water. Neither the yolk by itself, nor
the egg-white itself, would have had any selective value. Moreover,
the egg-white needed a vessel to contain it, otherwise its moisture
would have evaporated. So there had to be a shell made of a leathery
or limey material, as part of the evolutionary package-deal. But that
is not the end of the story. The reptilian embryo, because of this
shell, could not get rid of its waste products. The soft-shelled
amphibian embryo had the whole pond as a lavatory; the reptilian
embryo had to be provided with a kind of bladder. It is called the
allantois, and is in some respects the forerunner of the mammalian
placenta. But this problem having been solved, the embryo would
still remain trapped inside its tough shell; it needed a tool to
get out. The embryos of some fishes and amphibians, whose eggs are
surrounded by a gelatinous membrane, have glands on their snouts:
when the time is ripe, they secrete a chemical which dissolves the
membrane. But embryos surrounded by a hard shell need a mechanical
tool: thus snakes and lizards have a tooth transformed into a kind
of tin-opener, while birds have a caruncle -- a hard outgrowth near
the tip of their beaks which serves the same purpose, and is later
shed by the adult animal. [27]

 

Now according to the Darwinian schema, all these changes must have been
gradual, each small step caused by a chance mutation. But it is obvious
that each step, however small, required simultaneous, interdependent
changes affecting
all
the factors involved in the story. Thus the
liquid store in the albumen could not be kept in the egg without the
hard shell. But the shell would be useless, in fact murderous, without
the allantois and without the tin-opener. Each of these changes, if
they had occurred alone, would have been harmful, and the organisms thus
affected would have been weeded out by natural selection (or rather, as
suggested above, by 'natural elimination'). You cannot have an isolated
mutation A, preserve it over an incalculable number of generations until
mutation B occurs in the same lineage and so on to C and D. Each single
mutation would be wiped off the slate before it could be combined with
all the others. They are all interdependent within the organism -- which
is a functional whole, and not a mosaic. The doctrine that the coming
together of all requisite changes was due to a series of coincidences
is an affront not only to common sense but to the basic principles of
scientific explanation. In a recently published major work, Professor
Pierre Grassé (who, for thirty years, held the chair for evolution at
the Sorbonne without losing his Gallic wit) commented:

 

Where is the gambler, however obsessed with his passion, who would
be crazy enough to bet on the roulette of random evolution? The
creation, by grains of dust carried by the wind, of Dürer's
Melancholia has a probability less infinitesimal than the
construction of an eye through the mishaps which might befall the
DNA molecule -- mishaps which have no connection whatsoever
with the future functions of the eye.
Daydreaming is permissible, but science should not succumb to it.
[Grassé's italics] [28]

 

 

4

 

 

When we talk about the evolution of species, we mostly have the emergence
of new forms and physical structures in mind, as we see them displayed in
museums of natural history. But evolution creates not only new shapes;
it also creates new types of behaviour, new instinctual skills which
are innate and hereditary. If the forces behind the emergence of new
structures are obscure, those behind the evolution of innate skills are
shrouded in total darkness. As Nobel laureate Niko Tinbergen lamented:
'The backward position of ethology is striking . . . A genetics of
behaviour still has to be developed.' [29]

 

 

The reason for this is simple: neo-Darwinism does not possess the
theoretical tools to tackle the problem. The only explanation it has
to offer for the incredibly complex instinctual skills of animals is
that these too are produced by random mutations somehow affecting the
neural circuitry in the animal's brain and nervous system, which are then
preserved by 'natural selection'. It would be a wholesome exercise for
graduate students in biology to repeat this explanatory formula like a
Sanskrit mantra while watching a spider constructing its web, a blue-tit
shaping its nest, a badger constructing a dam, an oyster-catcher carrying
its prey skyward and dropping it on a hard rock, the social activities in
the welfare state of the honey-bee, and so on. One could fill a library
with illustrations of the staggeringly complex patterns of instinctual
activities of various species of animals which defy any explanation in
terms of the Darwinian mantra. I shall quote one of the less well-known
examples from Tinbergen:

 

A female of this species [the so-called digger wasp], when about to
lay an egg, digs a hole, kills or paralyses a caterpillar, and carries
it to the hole, where she stows it away after having deposited an
egg on it (phase a). This done, she digs another hole, in which an
egg is laid on a new caterpillar. In the meantime, the first egg has
hatched and the larva has begun to consume its store of food. The
mother wasp now turns her attention again to the first hole (phase
b), to which she brings some more moth larvae; then she does the
same in the second hole. She returns to the first hole for the third
time to bring a final batch of six or seven caterpillars (phase c),
after which she closes the hole and leaves it forever. In this way
she works in turn at two or even three holes, each in a different
phase of development. Baerends investigated the means by which the
wasp brought the right amount of food to each hole. He found that
the wasp visited all the holes each morning before leaving for the
hunting grounds. By changing the contents of the hole and watching
the subsequent behaviour of the wasp, he found that (1) by robbing
a hole he could force the wasp to bring far more food than usual;
and (2) by adding larvae to the hole's contents he could force her
to bring less food than usual. [30]
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