Chapter 1: Evolution in the Animal Kingdom established facts
and gaps in our Knowledge
If we are to believe certain researchers and their statements concerning the
phenomenon of life, there are no more secrets left to discover today “The
origins of life no longer form the subject of laboratory investigation”, stated
an eminent specialist in molecular biology in 1972. Always assuming these words
still carry a meaning, we may conclude that life does not contain any facts we
do not know. In reality, however, the situation is quite different, and there
are plenty of mysteries that still surround the origins of life.
Ingenious experiments have for many years been repeatedly performed by
biochemists and biophysicians in an attempt to prove the possibility of
spontaneously obtaining infinite quantities of certain chemical compounds found
in cells that are structurally highly complex. The scientists in question are of
the opinion that due to favourable physical influences, the compounds were able
spontaneously to combine together in an organized fashion, and by uniting, were
able to produce the fantastic complex we call the cell, or even more rudimentary
living organisms. A statement such as this is tantamount to saying that the
possibility of spontaneously forming steel particles from iron ore and coal at
high temperature could have led to the construction of the Eiffel Tower through
a series of happy coincidences that assembled the materials in proper order.
Even then, this comparison is very weak, for the actual structural complexity of
an elementary living organism is much more complex than the structure of the
Eiffel Tower, considered in 1889 to be a triumph of metal construction.
Those who ardently defend the role of chance base their opinions on experiments
of this kind, which claim to reproduce the possible origins of life. They repeat
the views of Miller, who in 1955 induced the formation of complex chemical
compounds; such as the amino acids present in cellular proteins, using electric
sparks in an atmosphere of gas composed of steam, methane, ammonia and hydrogen.
Needless to say, such experiments do not provide any explanation for the
organization of the components; nor do we have any idea whether this favourably
composed gas really existed in the earth's atmosphere two or three billion years
ago. A theory cannot be built on unknown facts such as these. Even if a gas of
this kind did exist in the earth's atmosphere; even if certain physical
conditions did trigger high-powered electrical phenomena; even if complex
organic chemical compounds had formed as a result of this fortunate combination
of circumstances, there is nothing to prove that they could have induced the
creation of living matter. The determining factor for this phenomenon remains
unknown. Some researchers admit that there is an enigma in this. Others point to
chance a convenient loophole that excuses them from acknowledging their
ignorance. We shall come back later to the reasons why it is impossible to
explain the phenomenon of life in terms such as these.
We must indeed turn to disciplines other than biochemistry to find the first
clues to the problem, and in particular we must look toward palaeontology.
Certain prehistoric animals and vegetals were not totally destroyed after their
death. Their remains lay buried in sedimentary terranes, protected thereby from
disintegration, and thus providing us with vestiges of these prehistoric life
forms. The state in which the vestiges are found sometimes allows us ''to draw
certain conclusions concerning the morphology and age of these once living
beings [The material studied by
Paleontology is limited to the bones and teeth]. It is in fact possible to gain an immediate idea of their age by
establishing the date of the terranes. This can be done by various methods, in
particular by radioactive measurements (radio chronology). For terranes that are
geologically less ancient, carbon 14 tests are used, while strontium and
rubidium tests are employed for older terranes. Having carried out these tests,
experts can then determine the age of the specimens under investigation.
Tests such as these lead us to think that living beings existed in a unicellular
state roughly one billion years ago
[The earth is 4.5 billion years old]. Although it cannot be stated for sure,
other forms may have existed before them. P: P. Grasse', in his book entitled
`Evolution du Vivant' [The Evolution of Living Organisms]
[Published by Albin Michel, Paris, 1973], mentions the
discovery of vestiges of much older organisms: for example, the existence of
organized life forms roughly 3.2 billion years ago in the rock formations of the
Transvaal. These forms could possibly represent tiny bacteria, smaller than 1 /
10,000 millimetres, as well as particles of amino acids. These organisms may
have employed amino acids, or possibly proteins contained in the sea...Other
microorganisms may also have been present in the sediments, such as cyanophilous
algae containing chlorophyll. The latter is a basic agent in photosynthesis, a
process by which complex organic compounds are formed from simple components
through the effect of light. Fossilized vegetation resembling algae and
filamentous bacteria have been found in more recent rock formations (2.3 billion
years old) near the shores of Lake Superior in Canada. The bacteria and certain
algae displayed an extremely simple structure, without the well known
differentiated elements of the cells. Similar samples dating back roughly one
billion years have been discovered in rock formations in Central Australia. This
stage probably gave way to a period in which algae of a different kind displayed
a genuine cell structure, with a nucleus and chromosomes containing molecules of
deoxyribonucleic acid, D.N.A for short. Many facts about these algae remain
unknown, however.
The pluricellular stage was to follow, but "in the animal kingdom, between uni
and pluricellular forms, there was still a hiatus". Two basic notions must be
mentioned immediately
- The aquatic origins of primitive organisms;
- The emergence of a growing complexity, passing from one form to another
combined with the appearance of new organisms.
This growing complexity is ever present throughout evolution: We find similar
fossilized vegetation at a much more `recent' period, 500 million years ago. We
cannot be certain, of course, that today's bacteria are identical to those said
to have appeared on earth as the first living organisms. They may have evolved
since then, although bacteria such as Escherichia Coli have indeed remained the
same for 250 million years.
Whatever the answer, the origins of life definitely appear to be aquatic.
According to today's thinking, it is impossible to conceive of life without
water. Any search for traces of life on other. planets begins with the question:
Has water been present there? On the earth's surface, the combination of certain
conditions including the presence of water was required for life to exist at
all.
The complexity of living matter in those very first organisms is not likely to
have been as great as it is in today's cells. Nevertheless, as P: P. Grasse'
points out: "In order for life to exist, there must be a production and exchange
of energy. This is only physically possible within a system that is
heterogeneous and complex. The established facts at the command of the biologist
provide a reason for him to concede that the first living form was of necessity
an organized entity". This leads Grasse' to stress the important fact that
today's bacteria, which appear to be the simplest living organisms, obviously
attain a high degree of complexity. They are indeed composed of thousands of
different molecules containing systems of catalysis that are themselves highly
numerous, and which enable the bacteria to synthesize their own substance, to
grow and to reproduce. The catalysis relies on enzymes, which act in infinitely
small quantities, each enzyme performing its own specific function.
Like the amoeba, unicellular life forms are composed of differentiated elements.
Their structure is amazingly complex, even though the cells are measured in
units of 1 / 1,000 of a millimetre. Within the fundamental substance of
unicellular forms, called cytoplasm, whose chemical structure is highly complex,
there are numerous differentiated elements, the most important of which is the
nucleus. This is composed of many parts, in particular the chromosomes
containing the genes. These control every single aspect of the cell's
functioning. They give orders through a system of information transfer, using
transmitters and a system to receive the orders as they come in. The chemical
vehicle supporting the genes has been clearly identified: It is deoxyribonucleic
acid (D.N.A.), a molecule of complex structure. The `messenger' is a related
molecule known as ribonucleic acid, R.N.A for short. Within the cell, it is this
system that ensures the formation of new proteins from simpler chemical elements
(synthesis of proteins).
It is difficult not to feel tremendous admiration for the molecular biologists
that first discovered these extremely complex mechanisms systems so perfectly
regulated to maintain life that the slightest malfunction leads to deformities
or monstrous growths (cancer is a case in point) and ends in death. As far as I
am concerned, however, the brilliant analysis of the way this system works (for
each and every cell is a kind of computer comprised of innumerable
interrelations) is just as amazing as the general conclusions cited above
concerning the supposed resolution of unexplained facts on the origins of life.
One very important question immediately springs to mind, based on the results of
these investigations: How could 'a system as complex as this have been formed?
Was it the work of chance, following a host of trials and errors? That seems
most unlikely. What other logical theories are there? It is common knowledge
that a computer will only function if it has been programmed, a fact that
implies the existence of a programming intellect, that provides the information
required to operate the system. That is the problem facing all thinking people
who seek an explanation to such questions; people who refuse to accept mere
words of groundless theories; people who will only acknowledge conclusions based
on facts. Given the present state of knowledge, however, science has not
provided any answer to this precise point.
The Diversity of Living Beings
There is tremendous diversity among living beings. From the most ancient times,
human observers have noted this diversity and have taken great pains to analyse
it in minute detail. Naturalists record the striking precision of certain
primitive peoples in their ability to distinguish between the species of animals
surrounding them. Having received no instruction from outside, these peoples
have compiled inventories that are not far off the work of an expert.
The first distinction to be made between living beings is the separation of the
animal and vegetable kingdoms. Although they share a common basic element the
cell as well as numerous constituent substances, they are different in several
ways. The vegetable kingdom is directly dependent on the earth for its
nourishment. It also requires a much greater capacity for producing complex
chemical compounds from simple bodies and light. The animal kingdom, on the
other hand; depends on the vegetable kingdom for its nourishment (at least with
regard to animals that have attained a certain degree of complexity), and
carnivores depend on other species of animal.
Henceforth, we shall concentrate uniquely on the animal kingdom, which is
extraordinarily varied and large. There may be as many as 1.5 million species
living on our planet. The list has continued to grow, especially in recent
decades, with the discoveries made in the marine world. Ever since the natural
sciences gained stature and importance in the seventeenth century, format
classifications have constantly appeared, each updated in turn as new data are
discovered.
Aristotle drew a distinction between animals with red blood and those without,
but no other studies of a serious nature were undertaken until the seventeenth
century, when more interesting characteristics began to attract attention. For
example: Some observers were struck by the question of respiration through the
lungs or the branchiae (fish gills), the existence or absence of a vertebral
skeleton (backbone), the anatomy of the heart (number of ventricles), or the
existence of hair as opposed to feathers. ' In the classifications that were to
follow, characteristics such as these remained distinctive of certain animal
groups.
The distribution of distinguishing attributes opened the way for classification
by group, with series of subdivisions. Thus the phyla
[Plural of Phylum] characterise the broad
basic divisions of the living beings presenting similar features, allowing us to
put them in the same group. Each phylum can be divided into clearly defined
classes; these are also determined by a certain number of specific
characteristics. Similarly, each class contains several clearly differentiated
orders, which nevertheless maintain the general features of their class and
phylum. An order consists of various families, the families are composed of
genera [Plural of genus], and the genera contain different species displaying both collective
and specific characteristics. Classification is further complicated, however, by
the existence of intermediary forms.
The first phylum of this classification is composed of unicellular forms, known
as protozoans. It includes the most primitive beings, which very probably
divided at some point in time, thus giving birth to pluricellular forms: This is
the first example of evolution in the course of time.
The structure of these pluricellular forms (spongiae, cnidariae and ctenophores)
became more complex as some acquired more specialized functions, without however
constituting organs with clearly defined attributes. For example, some provided
the covering of animals, others developed the ability to contract, or became
sensitive to outside stimuli, and others acquired reproductory functions. The
system grew more involved when a cavity appeared that served as a digestive
tract (cnidariae and ctenophores) and the sensory organs made their appearance.
This group did not as yet possess a head, however.
Embryological data have been of great value in establishing the various
classifications in the animal kingdom. Thus an important stage in the growth of
a structural complexity was reached with the early appearance during embryonic
development of an extra germ layer. The number of layers thus grew from two to
three, each layer ensuring the formation of clearly defined organs. Animals with
three germ layers were in turn divided into 2 groups: those containing a single
cavity (the digestive tract) and those with cavities that developed next to the
digestive tract and which were responsible for the formation of tissues and
various other organs. The broad divisions of the animal kingdom, here reduced to
their most basic terms, already seem to suggest a methodical organization.
The latter guided, the birth of the various phyla, of which 20 emerged (very
unevenly) into the following four groups
- The unicellular forms, constituting a unique phylum;
- The pluricellular beings containing two germ layers in the embryo
[The external layer (ectodern) and the
internal layer (endodern)], these
gave birth to three phyla;
- The pluricellular beings with three germ layers
[The first two layers plus a third (mesodern)
interposed between the two others] but containing only one
cavity, these accounted for six phyla.
- The group of animals with three germ layers and several cavities,
constituting the other twelve phyla, two of which are particularly important:
They are the arthropods which comprise the largest number of species in the
animal kingdom, among which we find the insects and the vertebrates, the latter
including fishes, reptiles, birds and mammals.
Nevertheless, the gaps in our knowledge of the transitions from one of these
groups to another are very wide indeed. In the case of the insects, one of the
most important groups, we know nothing whatsoever of their origins (P. P. Grasse)
Likewise, there are no fossils left to indicate the beginnings of the various
phyla. "Every explanation of the mechanism that governs the creative evolution
of the basic organizational plans is weighed down with hypotheses. This
statement should figure at the beginning of any book dealing with evolution.
Since we have no firm documentary evidence; statements on the origins of the
phyla can only be suppositions, opinions whose degree of feasibility we have no
way of measuring." P. P. Grasse's observation on the phyla should caution any
statement on the origins of the major basic divisions. From this point of view,
the determining causes of the phenomena in question are just as mysterious as
the birth of the most rudimentary life forms.
It is difficult to say at what period prior to the nineteenth century the
question of evolution in the animal kingdom was first raised. In the centuries
before Christ, several Greek philosophers had already perceived that the living
world was subject to transformations. Observers coming after them sometimes
displayed startling flashes of intuitive insight. Inevitably, however, their
conclusions arose from philosophical ideas or pure speculations. The fact that
they later proved to be correct, although the product of sheer guesswork; does
not lend any particular value to these early philosophical concepts. Indeed, we
should always bear in mind that during the same period, the same philosophers
maintained totally inaccurate theories with complete equanimity: the theories
concerning the existence of the universe in an identical state throughout
eternity, for example.
In 1801, however, Lamarck became the very first naturalist to put forward the
idea of evolution.. It appeared in his `Discours d'ouverture' (Inaugural
Speech), eight years ahead .of his `Philosophie zoologique' (Zoological
Philosophy). For the rest of his life, Lamarck collected arguments to support
his theory. Cuvier, the other famous French naturalist of the nineteenth
century, published his `Histoire des ossements fossiles' (History of Fossilized
Bones) in 1812. He compares present day animals with fossilized remains,
demonstrating the existence of extinct species. Cuvier's study does not,
however, support the idea of evolution. J. P. Lehmann suggests the following
reason for this: Cuvier thought that the fossils in question could not be older
than the maximum figure of several millennia allotted by the Bible to the earth
and the animal kingdom. Because, for example, the Egyptian mummy of an ibis did
not indicate that a change had taken place in today's animal, evolution did not
exist. In 1859, Darwin introduced the idea of the natural selection of species,
and it was not long before others attributed to Darwin's theory the general
concept of evolution. J. Roger has indeed pointed out "the actual word
`evolution' is not part of Darwin's original terminology. It did not appear
until the sixth edition of On the Origin of Species, and even then it was used
more as a general denial of the fixity of the created species than an
affirmation of Darwinian transformism proper." Hence, if we are to follow the
theories of P: P. Grasse in `L'homme en accusation' [Man Stands Accused] and of
J. Roger, we shall see that the true father of evolution is Lamarck (even though
his name is always associated with transformism), while Darwin is little more
than a transformist (even though he has always been considered the first
naturalist firmly to introduce the idea of evolution.) Later on, we shall take a
closer look at the ideas of both Lamarck and Darwin.
However that may be, the data provided by zoology and palaeontology combined
clearly furnished firm arguments from which to approach the question at issue.
Zoology strove to classify the different groups of orders, families, genera and
species, basing its distinctions mainly on anatomy, physiology, and embryology.
Palaeontology, on the other hand, ascertained (or tried to ascertain) at what
periods in time life forms appeared similar to those of today, and at what
periods beings now extinct first appeared then disappeared. This is an important
concept to remember, otherwise we run the risk of misinterpreting the
information provided by palaeontology: For example, the discovery of certain
fossil specimens in terranes dating from a precise geological age does not
necessarily mean that these life forms were inexistent before or after the age
in question. Errors of this kind are less likely to occur when fossilized forms
are highly numerous within a certain period, especially when there are no
specimens to be found in fossils pre- or postdating the specific period: In the
case of man, however, whenever there are very few genuine or supposedly genuine
remains, and whenever such vestiges are limited to bone fragments, the way is
open for a host of errors, as we shall see later on.
In spite of these reservations, we can derive many ideas from observing how a
clearly defined anatomical form present at a certain point in time has succeeded
a similar form with a less developed morphology existing in older terranes. This
change over a period of time may possibly reflect a better adaptation to what
may well have been new conditions of life. Observations such as these must,
however, be repeated with many different examples before one can seriously talk
of evolution. Only palaeontology can provide us with proof of this kind. Having
started promisingly in the early nineteenth century Palaeontology really came,
into its own after Darwin. The English naturalist did not employ any decisive
arguments from palaeontology: In most cases, his opinions rested on the study of
present day animals, suggesting an apparent natural selection that did not,
however, explain everything. Thus, Darwin's arguments are by no means
conclusive.
What can we say today about the definite or extremely probable data of
palaeontology when combined with facts drawn from our knowledge of zoology?
As we have, already seen, pluricellular life forms most, probably developed.
from unicellular forms. The most primitive pluricellular beings are likely to
have been the spongiae (sponges), which although not possessing clearly
differentiated organs already display a reproductive organization that is
sexual. From these primitive forms probably derive the cnidarian and ctenophores
mentioned earlier. The latter possess the rudiment's of organs and cells that
have acquired nervous and muscular functions: _ They are likely to have been
formed less than one billion years ago., The first invertebrates probably
appeared 500 or. 600 million years ago, along with molluscs, annulated worms,
and the first insects. The vertebrates came later, roughly 450 million years
ago, and likewise certain fishes, which continued to develop, thereafter. The
first. Terrestrial vertebrates (amphibians and reptiles) appeared some 350
million years ago, and following them came the mammals (180 million years ago)
and the birds (I35 million years ago). Life forms not only appeared however,
they also disappeared, sometimes in. very, large; quantities. The reptiles
provide an example of this phenomenon:: Having predominated for 200~million
years, they went into decline, so that today we have few vestiges to account for
reptile life over the past 60 or 70 million years. The mammals have taken their
`place' if one may call it that.
This deliberately brief and generalized survey shows, the magnitude; of the
evolution toward ever more developed and. complex forms. Also evident is the
extent to which forms could disappear (and not just the reptiles), thus bringing
considerable changes to the general, aspect of: the living world. , Finally we
must mention forms that have remained unchanged for hundreds of millions of
years cockroaches, to take an example from the insect world. There are, however,
many other groups, to which we shall later return, Each and every one of these
data raises considerable problems, thus indicating, the complexity of evolution.
We are forced to account not only for progressions, and regressions, but also,
for extinctions.
In view of this, the problem of the general evolution of life forms is
fantastically, vast and complex. It requires us to search into extremely diverse
fields: the natural sciences (botany and zoology), comparative anatomy,
palaeontology, embryology, and chemistry to mention only those that seem to have
provided the most evidence. There are, however, many evolutionary studies
published by researchers who, though undoubtedly extremely well informed in
their fields, have an unfortunate tendency to draw generalized conclusions
without any detailed knowledge of what experts from other fields have to say oh
the same subject.
The matter at hand is indeed so vast that very few specialists are able to
master each and every aspect of it: To do so would require tremendous
experience, as well as knowledge spanning a whole range of different
disciplines. It is for this reason that the observer who by definition is
willing to accept any proposition providing it is supported by solid arguments
remains very sceptical of conclusions too heavily based on data from a single
field of study. Thus it is difficult to accept certain theories, based on
molecular biology or mathematical research in genetics concerning the evolution
of living forms, when the authors of these theories quite obviously attach very
little importance to the work of their colleagues in other branches of
knowledge. For example, what about the work of researchers in the field of
palaeontology excavating ancient fossilized forms? What about the wealth of
relevant facts supplied by comparative anatomy and embryology? Sadly, we must
note that specialists in the basic sciences, preoccupied as they are with the
origins of life, the beginnings of man and the evolution of living forms, have
lost their appetite for arguments based on solid facts from the past.
This criticism is, in no way intended to undermine the tremendous value of
evolutionary data gleaned from the cell. It is simply aimed at the overly
exclusive use of these data, devoid of any interpretation. Unfortunately, this
shortcoming is very common nowadays. So many problems containing countless
facets are examined by specialists from a wide range of disciplines, only to be
viewed in the light that is most congenial to the eyes of the specialists in
question. A further difficulty is the frequent and unfortunate intervention of
ulterior motives of a religious or metaphysical kind, that quite obviously
underlie the opinions of many researchers. For example, a theorist f may rely
heavily on a material argument, glad to have discovered it if he thinks the
argument will support his cherished materialistic theory. But those who are not
informed may think it is dangerous to acknowledge the idea of evolution, even in
the animal kingdom, for fear that by extending this view to man, they may go
against the religious teachings they wish to uphold. In so doing, they are
unaware of the fact that certain aspects of modern discoveries that are usually
employed to support materialistic views may indeed offer a solid argument to
those of diametrically opposed opinions. All of which is to say, that questions
of this kind ought to be approached without any preconceived ideas at all.
Nowadays, there is a colossal quantity of data at the disposal of the
specialists who seek an answer to the questions raised here. In the past,
however, the material available for constructing a theory was very limited
indeed. The opinions expressed were strongly influenced by philosophical ideas
and religious beliefs. In spite of this however, certain ideas did escape these
influences, and in view of the concepts prevalent at the time, they were
absolutely revolutionary.
In the sixth century B.C., Anaximander of Miletus put forward the notion of
evolution in the animal kingdom. His theory appeared at the time the so called
Sacerdotal version of Genesis was being written on the other side of the
Mediterranean, in which there is mention of the creation of living beings `each
according to its kind'. In the century after, Empedocles appears to have sided
with the general concept of evolution. He does not, however, seem able to have
produced anything but a bizarre account of the origins of man that is entirely
the work of his vivid imagination. Lucretius, on the other, hand, expresses
ideas in his work `De Natura Rerum' [On Nature] that favour the notion of a
process of 'natural selection that preserves the strongest species and
eliminates the weakest.
The Bible was responsible for the widespread notion that the species were fixed
and unchanging, a concept that held sway until the nineteenth century. Even so,
Saint Augustine and several other Fathers of the Church mention certain
possibilities of transformation as a result of the potential attributes that God
bestowed on the world when He created it.
Buffon was the first thinker to uphold the idea of evolution, but he did so with
a certain amount of timidity. Initially, he had considered the species to be
fixed and unchanging, but as he grew older and his knowledge of nature
increased, he came to view them as in a state of evolution. To be precise,
however, he considered the families of animals to have come from a single
species, having acquired various characteristics in the course of time while
remaining within a certain biological framework. The fact is, he was not
prepared to admit that one species could transform itself into another; he only
accepted the existence of limited variations. For Buffon, conditions of life
climate, food, and domestication were the prime factors in the changes that took
place in animals. His doubts and hesitations are mentioned in P. P. Grass6's
book `Biologie Animale' [Animal Biology]
[Co-author M. Aron and P. P. Grasse,
published by Masson, Paris 1935]: “Buffon's work gives the impression
that the naturalist did not want to follow his thoughts through to the very end.
Anxious to preserve his peace and quiet, he was afraid of coming into violent
conflict with the preconceived ideas of his day. When the Sorbonne sharply
called him back into line, he agreed to everything they asked.”
Lamarck, on the other hand, enjoyed a far greater freedom to say what he liked.
Lamarck, the Father of Evolution
Although Lamarck had been the official Botanist to the French king, when the
Revolution broke out, he was lucky enough to secure himself a position where he
could study and teach without hindrance. Thus, in 1794, he occupied a teaching
post at the Museum National d'Histoire Naturelle [French National Museum of
Natural History]. Seven years later, in 1801, he outlined the theory of
evolution in his `Discours d'ouverture du 21 Floreal An 8'
[Inaugural Speech of the 21st: Day of Floreal, Year 8]
[According to the Revolutionary calender] several years before his
masterwork `La Philosophie zoologique' [Zoological Philosophy], which appeared
in 1809. Until his dying day, Lamarck worked tirelessly, amassing copious
evidence to support his theories. Although they are open to criticism on certain
points his opinions are unacceptable today they nevertheless represent a step
forward so enormous, that there is every reason to call Lamarck the `Father of
Evolution'. But for all this, he died in dreadful intellectual isolation;
criticized and mocked by his contemporaries, misjudged and underestimated, in
spite of the importance of his work as a naturalist.
Lamarck had shown the "relative unchangeability" of species, which are "only
temporarily invariable." If their conditions of life changed, Lamarck considered
that the species would change in "size, form, proportion between their various
parts, colour, firmness, agility and industriousness... Changes in their
environment modify their needs or create new ones; new habits lead to greater
use of certain organs and the neglect of others. When an organ is left unused,
it shrinks and may finally disappear altogether". (I owe to P. P. Grasse this
synopsis of Lamarck's ideas on the influence of environment.)
Indeed, it has been observed that the teeth of animals that do not chew their
food (the anteater or the whale, for example) tend to atrophy or not to emerge
at all. Another example is the mole; whose eyes are so tiny they often see
absolutely nothing. Going in the opposite direction, intense use of an organ
leads to its development
The feet of birds that live in water become webbed as a result of swimming, the
tongue of the anteater grows longer as a result of the way it extends its tongue
to catch and coat its victims with a sticky substance. The study of these
variations led Lamarck to conclude that when a change occurred, it was toward a
more complex organ (in the case of organs that develop as a result of intensive
use), and that variations of this kind were transmitted by heredity.
Critical Assessment of Lamarck's Theories
In criticizing Lamarck's theories, one must bear in mind the nature of the data
on which, in his day, Lamarck was able to base his ideas. While there are
undoubtedly points that he treats somewhat superficially, his ideas nevertheless
contain an element of truth. In Lamarck's eyes, the evidence was so striking
that in an age where others denied such evidence, the truth had to be
proclaimed. All the same, Lamarck overestimated the influence of environment,
and his idea that characteristics are automatically transferred by heredity is
no longer acceptable.
Zoologists have indeed pointed to the existence of changes that were induced by
environment the influence of food on the digestive tract, for example. It is a
well-known fact, however, that overworked muscles become hypertrophied.
Similarly, when a duplicate organ is removed, the remaining organ is quite
likely to grow bigger, although it does not change at all from a structural
point of view. An issue is the usefulness to the individual of the change thus
created, a point that has not been proven in the least. Nor is the change
definitive within the history of the species, for the hereditary nature of
acquired characteristics is a purely intellectual notion. Tests carried out
after a change of environment have shown that new characteristics are not passed
on to descendants. This is the sharpest criticism to be made of Lamarck's
theory. Nevertheless, Lamarck did indeed show the existence of a kind of
evolution in the animal kingdom: Where he went wrong was in his assessment of
the amplitude of evolution, as gauged through his observations. The explanation
he provided was unconvincing, and thus Lamarck was unable to gain acceptance for
his ideas. Cuvier, who favoured the concept of the fixity of species, vigorously
challenged him and it was Cuvier and those of his opinion who won the day.
Lamarck's ideas did not come into favour until several decades after his death,
when palaeontologists produced evidence lacking while Lamarck was alive of
morphological changes due to variations in environment. Moreover, the phrase
`influence of the environment' needs to be better understood, for we seem here
to be faced with a question of terminology requiring explanation. If by
`environment' we mean all the influences that are likely to produce an effect on
living organisms, then quite obviously changes may occur under such conditions.
Not all of Lamarck's theories are to be dissuaded.
In order to establish his doctrine, some fifty years after Lamarck; Darwin
advanced many more seemingly significant facts than his predecessor.
Unfortunately, however; Darwin thought everything could be explained through the
postulate of the all-pervading power of natural selection. There is no doubt,
moreover, that Darwin was strongly motivated by sociological considerations,
factors which should have no place in a scientific doctrine, and yet his work is
still very well known today. The following reasons may account for his
continuing fame: Darwin's arguments are extremely cleverly presented, and often
subtlety is more effective than the rigorousness of the arguments themselves.
Nor should we overlook the satisfaction of certain scientists who were quick to
use Darwin's theory to discredit Biblical teachings on the subject of the
origins of man and the fixity of species. Indeed, with regard to the evolution
of species, Darwin's theory was used to prove that man was descended from the
great apes. In fact, however, the animalistic origin of man is an idea that was
first put forward by Haeckel in 1868.
It is quite common today for people to confuse Darwinism with evolution a
misconception that is extremely annoying because it is totally wrong. Darwin
himself presented his theory in quite a different way, as the following extract
from On the Origin of Species [The
full title reads On the Origin of Species by Means Of Natural Selection or
The Preservation of Favoured Races In the Struggle for Life, London
1859. The texts quoted here are taken from the Pelican Classics Edition,
published by Penguin Books, 1982.] shows:
"Hence, as more individuals are produced than can possibly survive, there must
in every case be a struggle for existence, either one individual with another of
the same species, or with the individuals of distinct species, or with the
physical conditions of life... Can it, then, be thought improbable, Being that
variations useful to man have undoubtedly occurred, that other variations useful
in some way to each being in the great and complex battle of life, should
sometimes occur in the course of thousands of generations? If such do occur, can
we doubt (remembering that many more individuals are born than can possibly
survive) that individuals having any advantage, however slight, over others,
would have the best chance of surviving and of procreating their kind? On the
other hand, we may feel sure that any variation in the least degree injurious
would be rigidly destroyed. This preservation of favourable variations and the
rejection of injurious variations, I call Natural Selection."
In actual fact, Darwin indicated that he intended to put forward a theory on the
origin of species by means of natural selection or the preservation of favoured
races in the struggle for life. This became the banner of the evolutionists,
which they brandished in the fight between materialistic philosophy and
religious faith. The same banner is still being waved today in the same spirit.
Darwin has remained one of the idols of the atheistic arsenal, always ready to
support whatever ideas bring grist to their mill. As the reader of the present
book will see in chapter after chapter, the existence of evolution, even when
applied to the human species, no longer constitutes an argument that undermines
religious faith. Indeed, the latest studies of biological processes within the
cell reveal facts that are significant in a different way from the flimsily
based questions, which once formed the subject of discussion. They raised points
concerning the organization of life and in fact lead us in a direction totally
opposite to the main subject of past controversies.
All in all, Darwin's doctrine is very straight forward. He notes the obvious
fact that there is a wide variety in the number of characteristics present in
individuals belonging to a particular species, and he provides reasons for this
that are fairly similar to those of Lamarck. Darwin states that the reproductive
cells are modified as well, and that newly acquired attributes are hereditary.
He goes further than Lamarck, however, when tie talks of the advantages derived
from certain modifications that nature, by means of selection, perpetuates
through the elimination of the weakest in favour of those most able to survive
this pitiless process. According to Darwin, there is also a process of sexual
selection in which the females choose the strongest males...
The concept of natural selection exercised a tremendous fascination, and even
today, the followers of Darwin consider the advocate of natural selection to be
the greatest genius who ever worked in the field of natural sciences. He still
remains one of the most venerated zoologists. The highest honours were accorded
to him at his death. Although his work had provided arguments to support atheism
in the confrontation between religion and science that raged in the second half
of the nineteenth century, his mortal remains were interred by the British
nation in Westminster Abbey, London.
In actual fact, Darwin's work contains two aspects: The first is scientific, but
in spite of the impressive quantity of data observed by Darwin, when all is said
and done, the scientific aspect is far from solid; while his observations are
extremely interesting from the point of view of the various species, they do not
tell us very much about evolution itself and that is quite a different matter.
The second aspect, which is philosophical, is very strongly stressed by Darwin
and very clearly expressed.
The Ideas of Malthus as Applied to the Animal Kingdom
Darwin does not hide the influence of Malthus' ideas on his own concept of
natural selection. The following quotation from Darwin is taken from P. P.
Grasses work `L'homme en accusation'
[Man Stands Accused]: "In the next chapter
the. Struggle for Existence amongst all organic beings throughout the world,
which inevitably follows from their high geometrical powers of increase, will be
treated of. This is the doctrine of Malthus, applied to the whole animal and
vegetable kingdoms." This statement appears 'in the introduction to the second
edition of On the Origin of Species, 1860.
Before applying a socio economic theory to data observed in the animal kingdom a
field that by definition has nothing to do with socio economic theory, Darwin
had indeed pursued very logically his thoughts concerning the natural phenomena
he had so carefully observed. From 1831 to 1836, he accompanied the mission of
the ship the Beagle in the South Atlantic and the Pacific, serving as a
naturalist. The voyage provided Darwin with ample opportunity to observe on
land. Thus he was struck by the modifications displayed in the species studied,
corresponding to the places in which they lived. From this he derived the notion
of an absence of fixity, and he compared this to the selective breeding of
domestic animals by humans in an effort to improve the various species. The
question that sprang to his mind was: How could selection be applied to
organisms living in their natural state? By this I think what he probably meant
was: Do the factors that man uses when making his selections for the purpose of
cross breeding animals possess an equivalent in nature? There does indeed seem
to be spontaneous selection between animals in their natural state. Thus a
question was raised and a hypothesis suggested, but in the answer that followed
there was no certainty whatsoever.
It is very difficult to understand how Darwin could have found justification for
this theory in the ideas put forward by Malthus. The later was an Anglican
clergyman whose initial interest was in demographic factors and their economic
consequences. In 1798, he anonymously published an Essay on the Principle of
Population in which he proposed various solutions. Some of them are totally
inhuman, such as the famous Poor Law, which abolished assistance to those who
produced nothing and lived off the rich. As far as Malthus was concerned,
selection operated among human beings: Only those most able to produce deserved
to survive, those less favoured by nature were destined to disappear. In view of
the dreadful misery present among the working classes at this early stage in the
industrial revolution, such total lack of basic human charity is staggering.
Darwin saw interesting ideas in the propositions of Malthus, and he applied to
human beings the hypothesis of a selective process that ensured the survival of
the fittest and most able at the expense of the weak a selection that nature
itself would operate.
Those are the facts, and if Darwin's statement were not there, written in black
and white, who would ever think of associating his early ideas with the
pitilessly rigid prescriptions of Malthus? In `L'homme en accusation' (Man
Stands Accused) P. P. Grasse is extremely critical of Darwin for having drawn
his inspiration from Malthus and for the unfortunate influence he created:
"Due to its basic precepts and final conclusions, Darwinism is the most
antireligious and most materialistic doctrine in existence." P. P. Grasse is
amazed that Christian men of science do not seem to be aware of this. He goes on
to note that "Karl Marx was much more perceptive. When he read
On the Origin of
Species, he recognized the materialistic, atheistic inspiration of the work.
That is why he admired it so much and why he used it in the way he did. In its
pages, Marx found the material needed to dissolve all religious belief, an
opinion shared by the founders of the Soviet Union, especially Lenin... They
created a Museum of Darwinism in Moscow in order to combat `Christian
obscurantism' with the help of scientific data!"
Criticism of Darwin's Theory
It is patently clear that if left to them, animals or plants that contain a
defect or infirmity will be the first to disappear. There is little need to cite
examples supporting this statement of the obvious. But to go from this to saying
that selection in nature ensures only the survival of the strongest and fittest
is quite a different matter. Our response must be much more subtle.
When we observe animal populations living within a certain territory, we are
well aware that a system of balances is in operation; even though the balances
may not be the same everywhere in one section of the territory a species
predominates, in, another it is supplanted by a different species. In cases such
as this, there is no doubt that selection is operating within a single
population; but it does not influence biological evolution as a whole.
Observations are further distorted by the arrival of cataclysms or extreme
changes in climate over the ages. Such events may affect vast areas, striking
blindly, and without any of the selective influences one might expect to find in
the disappearance of a population: Flooding from rivers or the sea, or fires for
example, can cause great devastation, but that does not mean that their victims
were specially selected. Likewise during the various geological eras,
glaciations struck indiscriminately.
An objection to Darwin's theory that P. P. Grasse raises is the fact that death
does not always make a distinction. It does not always kill the weakest and
preserve the strongest, as Darwin would like us to think. P. P. Grasse gives
precise examples of cases where it is not possible to know, at 'a certain stage
in the metamorphosis of living beings, why it is that one batch evolves normally
and another does not. When animals fight, it is not always the strongest and
best equipped who win the battle: The percentage of animals who are victorious
depends on factors such as chance and circumstance. The idea of sexual selection
is also open to considerable criticism: It is very unrealistic to imagine that
the female always chooses the strongest male, .for the element of chance in such
encounters outweighs individual preferences.
What evidence is there of the power of selection to provoke the emergence of new
forms? Darwin likened natural selection to the artificial selection practised by
.man. In actual fact, however, artificial selection does not create new species;
all it does is influence certain characteristics. The individuals themselves do
not `take leave' of their species, as it were. Artificial selection does not
trigger the formation of new organs, it does not lead to the creation of a new
genus, nor does it engender a new type of organization. These facts are very
clearly stated by P. P. Grasse who cites the example of colon bacillus and
drosophila, organisms, which can undergo mutations while preserving the
characteristics of their species that have been passed down for millions of
years. Thus the minor individual variations mentioned by Darwin are by no means
hereditary a point on which Darwin's theory is just as open to criticism as
Lamarck's.
Data on Evolution in the Animal Kingdom that Contradict Darwinian Concepts
In this section, we shall quote the objections raised by P: P. Grasse, the first
of which is Darwin's own admission that his doctrine was incomplete: "Judging
from letters (and I have just seen one from Thwaites to Hooker), and from
remarks, the most serious omission in my book was not explaining how it is, as I
believe, that all forms do not necessarily advance, how there can be simple
organisms still existing..." (Letter to Asa Gray, May 22, 1860, from
The Life
and Letters of Charles Darwin, by Francis Darwin, 3 vols, published by John
Murray, 1887.)
Darwin speaks of the `progress' that natural selection ought to ensure in living
beings, by which he confuses `progress' with growing organizational complexity,
an essential aspect of evolution to which we shall return. Elsewhere, he
expresses his amazement at the existence of living forms which have not changed
at all over the course of time but have remained at the stage of very simple
organisms: This is a phenomenon that is easily explained today in terms of
modern ideas on mutagenesis. Every living being is affected by mutagenesis,
minor variations which do not, however, cause the organisms concerned to leave
the framework of their species.
For example, zoologists are very familiar with the so-called `pan chronic'
species, which have remained the same throughout the course of time. Blue algae
are a case in point: There is every reason to think that these organisms have
been in existence for at least one billion years, and yet they are still the
same today. Other examples are the ferro-bacteria, sponges, molluscs, and
animals such as the opossum or the famous coelacanth which, though hundreds of
millions of years old, have not changed at all. The coelacanth caused great
excitement when it was discovered off the coast of South Africa in 1938. It is a
fish, over 4 1/2 feet long, that is thought to have appeared roughly 300
millions years ago. Several other examples of this fish have been caught in more
recent times almost to order, for the local fishermen are familiar with the
coelacanth. Examination of these fish provided important information on the
anatomy and physiology of a species, which, like so many others, refused to
conform to the natural selection put forward by Darwin. At the same time
however, none of these organisms has ceased to undergo mutations a process that
is inevitable. As far as the fish are concerned, however, their evolution has
come to an end. If we seek the reason why, we find that Darwin's theory is
unable to provide an answer that both agrees with his doctrine and explains the
preservation of these hereditary characteristics.
According to the law of natural selection, such imperfections as the excessive
development of a single characteristic should not be allowed to develop and
perpetuate themselves, to the extent that they harm the animal or vegetal
concerned. Nevertheless, it is a well-known fact that certain conifer plants
produce chemical compounds that irresistibly attract coleoptera which then
devour them. The production of these chemical, compounds is therefore
responsible for the death of the plant. This process has been going on for
millions of, years: Natural selection does not intervene to save pine and fir
trees from destruction by insects.
Similarly, the antelope is able to escape its enemies by its extreme speed, and
yet there are species of this animal whose hooves contain glands that secrete a
particular odour, which, as the antelope runs, is left on the ground. All the
attacking carnivore has to do is follow the scent in order to track down its
prey. Thus the graceful antelope is left unprotected by the theories of Darwin!
Another example; of a harmful individual attribute is the excessive growth of
horns, which can constitute a handicap. Finally, we are all familiar with the
case of the deer, whose antlers impede its movement through the forest.
Studies of the coelacanth have shown the extent to which this fish contains
characteristics that are paradoxical to the zoologist. If natural selection were
genuinely present, these characteristics ought by rights to have disappeared,
thus providing the coelacanth with a more functional morphology. The fact is;
however, nothing has changed for several hundred million years.
If we examine the argument put forward by zoological specialists who are opposed
to Darwinism, we shall undoubtedly see that it is sometimes quite difficult to
distinguish between a harmful and a beneficial morphological change in an
animal. For example, snakes have lost all their limbs, but that does not mean
they have been placed in an inferior state. Given a case such as this, what
right have we to speak of an animal that has `regressed'? The example of the
snake is indeed extremely revealing, for the loss of its limbs was accompanied
by other major modifications of its skeleton and numerous viscera, affecting its
general anatomy. Zoologists are at a loss to explain in Darwinian terms such
sweeping changes; they are modifications, which were perfectly coordinated over
the course of time, and the succession of phenomena here appears infinitely
complex, from an anatomical point of view. Thus we must seek an explanation
different from the intellectual view that casts everything in terms of finality
in spite of what the Darwinians may say.
In his book `L'Evolution du monde vivant' [The Evolution of the Living World]
[Published by Plon, Paris, 1950. The fac-simile
of Darwin's letter is contained in this book. M. Vernet notes that the letter is
preserved at the British Museum (Ref A DD MS. 37725f.6)],
M. Vernet cites a letter that Darwin wrote to Thomas Thorton Esq. in 1861.
Darwin states quite clearly that he is aware of having failed' to explain
evolution:
"But 1 believe in natural selection, not because, I can prove, in any single
case; that it has changed one species into another, but because it groups and
explains well (as it seems to me) a host of facts in classification, embryology,
morphology, rudimentary organs, geological succession and distribution..."
Darwin was perfectly well aware; therefore, that the theories he advanced
concerned the possible influence of natural selection on
a species that did not,
however, transform itself into another species. Furthermore, when Darwin put
forward the idea of natural selection as a tentative explanation of his
objective observations, he was simply proposing a theory. By definition, a
theory is no more than a hypothesis that for a while serves to link facts of
various kinds by way of an explanation. While it may prove useful at a certain
stage in human knowledge; however, it is the future that determines whether a
certain hypothesis is valid or not. The validity of Darwin's theory has not yet
been proven.
Unfortunately for Darwinism; the theory was used for ideological purposes. We
are now much more familiar with the process of evolution, owing to more
consistent data such as the information provided by paleontology and the natural
sciences, as well as new knowledge, acquired since Darwin, concerning heredity
(genetics) and biology (especially molecular biology.) In spite of this, we are
still, saddled with the theory formulated by Darwin over a century ago; there
are those who do not wish to see its ideological success diminished. That is why
we today have the `neo Darwinians' who hope to use modern discoveries to combine
the basic idea of selection with new data. We shall see later on that a
combination of this kind is also open to severe criticism.
I should like to conclude this discussion of Darwinism proper by turning once
again to the opinions of P: P. Grasse. The reason I have quoted this eminent
specialist in evolution so often is that I consider his opinions to be extremely
well argued and logical. This is what P. P. Grasse has to say about the
influence of Darwin's work as a whole:
“It is significant but often forgotten that Darwin named the book that brought
him fame, On the Origin of Species. He sought the mechanism through which one
species transformed itself into another; he did not envisage the origin of the
basic types of organization. He not only refused to give attention to the
general problems concerning the unity of the organizational plan, but he
actively distrusted them. He expresses this as follows: "It is so easy to hide
our ignorance under such expressions as the `plan of creation', `unity of
design', & c., and to think that we give an explanation when we only restate a
fact." The expression `plan of creation' does indeed suggest a tendentious
interpretation, which we reject. That does not mean, however, that Darwin's
reasoning was correct when he refused to consider the predominant problems of
evolution. In his eyes, natural selection explained everything; he therefore
considered an animal in terms of a species. His whole system of explanation was
conceived in such a way that he referred only to variations that did not go
beyond the species. It is a strange fact; however, that Darwin never took the
trouble to define what he meant by `species', not even in the glossary that
appears at the end of On the Origin of Species.”
[P. P. Grasse, "Biologie moleculaire,
mutagenese et evolution' (Molecular Biology.Mutagenesis and Evolution),
Masson, Paris, 1978 ]
Neo Darwinism
In order to realize the extent to which Darwin is still revered today, one has
to have come into contact with the academic world in America, especially in the
fields of biology, genetics or evolution. Darwin is venerated, however, in spite
of the fact that his theory is outdated and his concepts extremely fragile. The
criticism that may legitimately be levelled at Darwinism, as a result of the
proven data on evolution collected by palaeontologists, zoologists and
botanists, exercises a certain influence on the opinions of specialists in
Europe. It has virtually no impact on researchers in the United States, who
uphold theories that are for the most part conceived in the laboratory. One is
tempted to ask whether it is possible to be anything but a Darwinian in America.
In some people's opinion, the idea of criticizing Darwin is the same as saying
that the theories of Einstein are totally worthless. The difference between them
lies in the fact that Einstein's theories were solidly based and their validity
was subsequently demonstrated. There are indeed people in Europe who persist in
their infatuation with the role of natural selection in evolution, but perhaps
fewer than in the United States.
The predominant idea at the moment seems to be the integration into the system
of newly acquired genetic discoveries: Natural selection no longer intervenes to
favour the survival of the fittest, but rather in terms of probabilities. It
operates through a statistical process that raises the likelihood that the
fittest will be the individuals who transmit their characteristics. Thus the
process of natural selection acts as the agent ensuring the preferential
transmission of attributes registered in the genes. The idea of sexual selection
lives again in the minds of the neo-Darwinians...
Genetics deals with the subject of heredity, and as we shall see very clearly
later on, today's discoveries in this field allow us to arrive at certain very
important theories and practical conclusions for genetics deals with present day
phenomena. With regard to evolution, genetics is currently, attempting to study
mutations that modify certain minor characteristics, concentrating its research
on living beings that reproduce very rapidly. As it happens, however, evolution
that takes place in the animal kingdom over the course of time has a much
greater effect than the minimal variations observed in present day organisms.
That is why zoologists specialising in evolution question the extrapolations of
the geneticists; the latter choose the wrong method of applied study when
investigating present day organisms, and this leads them to mistaken
interpretations of past events. In short, they are not studying the real
questions of evolution.
If evolution had indeed occurred in the manner suggested by the Darwinians and
neo-Darwinians in other words as a result of minimal variations (which as far as
we know leave living beings within the framework of their species) how much time
would have been required for the formation of the organized types that exist
today? Tens of billions of years! Hundreds of billions! In actual fact, the
amount of time needed for the transition from unicellular life forms to the most
recent higher mammals was just over one billion years. Furthermore, examination
of the transitions undergone by man from the Australopithecus to present day
Homo Sapiens indicate that modifications took place at amazing speed within a
very small population (we know this from the rarity of fossils.) This is to be
compared with the fact that for hundreds of millions of years bacteria and
insects such as cockroaches have remained more or less identical in spite of the
tremendous variety of individuals and genetic mutations. Neo Darwinism takes no
account of these fundamental points; thus invalidating the very basis of its
theory.
We need an explanation of the variable speed of evolution that is different from
the spontaneous, unpredictable mutations presented by the neo Darwinians as the
motivating force behind an evolution that is controlled by a so called process
of natural selection. This leads us to think that modern followers of Darwinian
theory have no coherent explanation of evolution to offer us. Their explanatory
suggestions however brilliant do not seem applicable to a real situation that
requires real answers.
Socio-biology
With E.O. Wilson [E.O. Wilson,
Sociobiology. The New Synthesis. Belknap Press of Harvard University
Press, Cambridge (Mass) and London, 1975] and American socio biology, which gave allegiance to neo
Darwinism, the explanatory theories of all human action, based on the strict
correlation between human and animal motivations, have reached the height of
their art. Indeed, E.O. Wilson has given a more detailed view of his opinions in
a work published quite recently [E.O.
Wilson, On Human Nature, Harvard University Press. Cambridge
(Mass). 1978]. Wilson and his followers have studied the behaviour of animal communities, some of which such as the termites are
remarkably well organized, and the conduct of man, whose actions Wilson
considers to be entirely the result of impulses emanating from the genes. This
leads to an `animalisation' of man that is scientifically unacceptable. If the
damage caused by Wilson's ideas only affected the strict framework of
theoretical interpretation, it would not be that serious. What is highly
disturbing is that in the suggestions put forward for the practical application
of this theory, man is relegated to the level of an insect, faithfully executing
orders within an extremely well organized animalistic society.
Wilson and the advocates of socio-biology further suggest that the scientist
ought to exercise the right to modify man at will by genetic procedures. As we
shall see later on, this would transform human society supposedly for the
better, in the eyes of those who uphold these theories according so called
scientific bases. What this in fact amounts to is nothing other than the social
ideal that was once constructed on principles of race. We all know that it led
to the most widespread slaughter in the history of modern times and to the final
collapse of the `master race'. E.O. Wilson and socio-biology open prospects that
are utterly degrading for mankind. I shall return to them in my discussion of
what I call `genetic manipulation' and others euphemistically call `genetic
engineering.
The preceding chapter drew attention to the gap separating two groups: On one
hand the zoologists, whose study of evolution takes serious account of the
discoveries of palaeontology, thus enabling zoologists to establish the
chronological succession of developments (with a few gaps, needless to say.) On
the other hand, there are those who think they can reconstruct the course of
evolution by using data observed in today's living beings, as well as laboratory
researchers working on organisms. that reproduce themselves rapidly, and
studying the descendants of these organisms. Thus this group arrives at
suggestions as to what may have taken place long ago.
No serious study of evolution can be undertaken without recourse to both groups.
The first establishes the facts, and the second (especially the laboratory
researchers) provides extremely helpful data to explain how events take place or
may have taken place, and on a more general level, suggesting answers if there
are any to be found.
What does each of these groups have to offer? The first lays before us concrete
data on events that happened long ago, sometimes with a slight tendency. to
underplay the gaps in our knowledge of the order in which these events took
place. By and large, however, the information provided deals with concrete
facts. The second group seems either to have forgotten or not to have taken
account of these events. Instead, it supplies us with explanatory theories,
which can hardly be said to apply to real facts or events. If we lose sight of
reality, however; the most sophisticated reasoning can only lead to inaccurate
statements: That is exactly what is currently happening in the case of certain
theories, such as neo Darwinism and others, as we shall see later on.
Let us therefore turn to the data supplied by those accustomed to objectively
setting forth the facts of a history for it is indeed a history without deciding
in advance the factors that may have influenced the course of evolution.
From the most elementary books on the natural sciences onward, we have been
taught that the animal and vegetal species in existence today could be grouped
according to certain characteristics. We also learned that there were many sorts
of groups in the broadest sense of the word composed of families that all share
a certain number of features. The number of groups has continued to increase
with the passage of time, owing to knowledge newly acquired by zoology and also
as a result of the discovery of fossilized animals that no longer exist today,
having left us nothing but vestiges. All these data seem to increase the
diversity of living beings.
The groupings established by naturalists and palaeontologists have enabled us to
distinguish compartments into which we can divide living beings who share a
number of common characteristics. From this arise extremely important concepts;
For example, the existence of an order in which the various categories appeared
throughout the different eras, and the fact that each category tended tar
transform itself in a very specific way as time passed.
From the most ancient times onward, organisms began to appear (as stated
earlier) that acquired a more and more complex structure without, however,
creating any kind of disorder or anarchy. After a period of one pr two billion
years, distinguished by the existence of living beings containing simple
structures (although already extremely complex from a biological point of view),
organizational types developed that included today's members of the animal
kingdom; as well as extinct species. The phyla in question did not, however,
continue developing indefinitely to the detriment of more simple forms. A halt
was reached roughly 350 million years ago, the period in which the first
vertebrates appeared. Since then, particular classes of living beings have
formed within a phylum which preserve the main features of the phylum while
acquiring new characteristics. For example, in the case of the vertebrates, the
birth of cyclostomes (fish without jaws, such as lampreys) was accompanied by
the appearance of fish that, in certain instances, led to the formation of the
amphibians (batrachians, such as the frog); among the latter, some amphibians
gave birth to the reptiles, from which one group detached itself to form the
mammals, while another later became the birds. Of all the living beings thus
formed, the birds came last, appearing some 135 million years ago. Since the
birds, no new class has appeared in the animal kingdom.
A remarkable phenomenon is the fact that the characteristics of a class
gradually increase over successive generations, while now and again, secondary
branches appear which acquire, new specific features that constitute the origin
of new forms. Some of the branches proliferate and survive while others
disappear more or less quickly, but these secondary branches never represent the
beginnings of new phyla. There was a period in which the general organizational
plans appeared, and once that period was over and the plans fulfilled, there
were no subsequent plans. Henceforth, all that could appear would be
subdivisions.
The events of evolution took place at highly variable speeds right up until the
time the final form was attained that marked a halt in the process. As a result,
there are species among today's living organisms that quickly acquired their
definitive form and have retained it until the present day: for example certain
molluscs, insects, and fishes that have remained the same, while closely related
forms have undergone a long and far reaching process of evolution. Thus the
coelacanth has not evolved for 200 or 300 million years. Vestiges of primitive
phyla are very common in nature, indicating forms that have remained at an
initial stage without evolving at all
for example bacteria, unicellular organisms, sponges, jellyfishes, various
coral, and particularly prolific insects, of which there exist roughly 100,000
species for a single order (the collembolae, for instance.) As opposed to this,
there are examples of revivals after, a long halt: Zoologists point to families
that experienced an intense period of evolution, only to peter out later on.
While there is quite clearly a lack of continuity in evolution as a whole, this
does not exclude the ever-present order in the general march of events.
Within the complexity of organization, there nevertheless appears a progressive
tendency toward a type that is finally to be constituted, containing of course
variations both small and great. The horse is always cited as an example of a
type whose evolution took place on several continents, gradually arriving at its
definitive form in spite of the diversity of environments.
The irreversible evolution that occurs within an order creates new forms by
increasing the complexity of structures with the passage of time: When all is
said and done, there is a direct link between the passing of time and the
complexity of organization.
One of the best and most readily understood examples of this growing complexity
is the evolution of the nervous system in the animal kingdom. Originally non
existent, a `rough outline' appeared in the form of cells that contained the
ability to feel; this was followed by the beginnings of a system of sensory and
motor relations leading to the tremendous complexity now present in the higher
vertebrates. With the development of the brain; an extraordinary ability to
retain information was acquired, allowing innate features to manifest
themselves, and, in the case of man, permitting the psyche to develop at the
same time as acquired behaviour, while man's innate behaviour correspondingly
decreased. We shall return to these fundamental concepts in Part Two of the
present work, which deals with man.
This notion of the production of new and ever more complex structures completely
rules out the effects of chance. Unpredictable, fortuitous variations even when
corrected by natural selection could never have ensured such progression in
perfect order. The progression implies that the variations were simultaneous and
coordinated so as to obtain a growing organizational complexity. Science is able
to analyse the phenomenon; it knows that the existence of genes implies that a
particular phylum cannot produce a certain class derived from another phylum,
and that a particular family from a specific class cannot one day appear in
another class. Evolution is quite obviously oriented, even though the term may
shock those who will only acknowledge phenomena whose existence can be explained
as if man could explain everything. Since science is unable to solve the enigma,
however, some people cast it aside and refuse to incorporate it into their way
of thinking. Thus the essential features of evolution in the animal kingdom are
not taken into consideration by those who are unwilling to finish a study by
admitting that they are at a loss to account for the reasons behind the
phenomenon. A theory such as `chance and necessity' will provide a clear
illustration of this attitude, as we shall see.
Since the structure of living beings seems to have progressed in a perfectly
coordinated way over the course of time, how is it that in this context people
have paradoxically come to speak of chance? Is there really any need to stop and
examine the theory that chance plays an active part? Certainly not: If we take
account of the known facts of evolution. We must indeed examine the role of
chance, however, in view of the fact that it has been fiercely defended by some
and has attracted so much attention that the inaccuracy of the theory needs to
be pointed out.
As for necessity, whim should here be understood to mean `the impossibility of
the contrary, it is difficult to find any foundation for such an idea. In the
explanation of the phenomena discussed here, the place occupied by necessity is,
to say the least, extremely dubious.
We have already discussed the role of chance in the origins and evolution of
life. The philosophers of Antiquity, ignorant as they were of the realities of
the universe, may be excused for conceiving (like Democritus) that eternal
matter acted to produce all the cosmic systems and everything, in the universe,
animate and inanimate forms alike. While Democritus could not have had the
faintest idea of cell structure, however, the same cannot be said of today's
scientists, especially when they are experts in molecular biology. What is one
to think, therefore, when the role of chance is upheld by people who are aware
of the immense complexity of living matter as a result of their own brilliant
discoveries and analyses of it? Basic common sense tells us that the very last
factor capable of explaining the existence of a highly complex organization is
chance.
Even if we move our attention from the cell itself to its tiniest molecular
elements, we shall see that physicists and chemists have long ago abandoned the
theory that the cell was formed by chance:
Indeed, in order for the smallest macromolecules of a cell to form as a result
of repeated attempts, such enormous quantities of matter would have to have been
processed that they would have filled literally colossal masses on a scale
comparable to the volume of the earth itself. This is totally inconceivable.
Oparine, a modern Russian biologist who is a well known materialist, rejects
outright the theory of chance in the formation of life: "The entire network of
metabolic reactions is not only strictly coordinated, but also oriented toward
the perpetual preservation and reproduction of the totality of conditions set by
the external environment. This highly organized orientation characteristic of
life cannot be the result of chance." (From an article entitled `Etat actuel du
probleme de l origine de la vie et ses perspectives' [The Current State of the
Problem of the Origin of Life and Its Future Perspectives], which appeared in
the French journal `Biogenese' (Biogenesis), Paris, 1967, p. 19.)
In his work, The Origin of Life, Oparine draws particularly relevant comparisons
to help the layman see the logicality of theories pointing toward chance. As he
wrote in 1954:
"It is as if one jumbled together the printing blocks representing the twenty
eight letters of the alphabet, in the hope that by chance they will fall into
the pattern of a poem that we know. Only through knowledge and careful
arrangement of the letter s and. words in a poem, however, can we produce the
poem from the letters."
There are of course certain theories that can be put forward, but some of them
are quite obviously absurd. Oparine cites the following example in his book:
"Physicists state that it is theoretically possible for the table at which I am
writing to rise by chance, due to the orientation in the same direction of the
thermic movement of all its molecules. Nobody is likely, however, to take
account of this in his experimental work or in his practical activity as a.
whole."
I owe these important quotations from Oparine to the highly documented book by
Claude Tresmontant entitled ‘Comment se pose aujourd'hui le probleme de
l'existence de Dieu' [How Does the Problem of the Existence of God Appear
Today?] [Published by Seuil,
Paris 1971] they appear in Claude Tresmontant's commentary on the theories of J.
Monod published in ‘Le Hasard et la Necessite' [Chance and Necessity]
[Published by Seuil, Paris 1970].
As early as 1967, J. Monod had stated in his inaugural speech at the College de
France that `any and every fortuitous accident...' in the reproduction of the
genetic programme throughout evolution explained the creation of new structures:
"Evolution, the emergence of complex structures from simple forms, is therefore
the result of the very imperfections in the system preserving the structures
represented by the cell... It may be said that the same fortuitous events which,
in an inanimate system, would accumulate to the point where all structures
disappeared, lead, in the biosphere; to the creation of new and increasingly
complex structures." Claude Tresmontant quotes another passage from J. Monod
which appeared in a French journal entitled `Raison presente' [Present Reason],
no 5, 1968: "The only possible source of evolution has been in the fortuitous
accidents that have occurred in the structure of D.N.A. They are what are known
as `mutations'."
It is difficult to understand why J. Monod therefore decided that chance alone
was the intervening factor in this case. After all, he himself stressed his
ignorance an ignorance we all share concerning the origins of genetic
information: "The major problem is the origin of the genetic code and the
mechanism by which it is expressed. Indeed, one cannot talk so much of a
`problem' as of a genuine enigma." In fact, however, the enigma is twofold: It
not only affects the origin of the genetic code, but also the increase in the
data contained in the genes leading to the birth of more and more complex
structures; an increase which, as we shall see later on, is expressed through
chemical compounds.
The theory of chance as the force creating highly organized structures is at
odds with the facts. We have already seen that evolution, in all its shapes and
forms, takes place in an ordered fashion, complete with genuine lineages
observing an orientation that is perfectly clear: We cannot logically argue
therefore, that `fortuitous accidents' to use J. Monod's phrase could have
produced anything but chaos. We know in fact that within the same overall plan;
concordant variations must combine over periods of time, which are often very
long, in order for entirely new forms to appear. It is hardly surprising,
therefore, that eminent zoologists such as P. P. Grasse, who are thoroughly
familiar with the question, are incensed by explanations, which take no account
of the real situation. Among P. P. Grasses many critical comments, I shall quote
the following observation concerning an aspect of the evolution of the mammals
from the reptiles, an event that lasted some 50 million years: "In the mammal,
all the sensory organs evolved at more or less the same time. When we try to
imagine just what their formation required in terms of simultaneous, or almost
simultaneous mutations, all of them taking place at the right moment and capable
of fulfilling the needs expected of them, we remain speechless at the sight of
so much harmony, so many fortunate coincidences, all of them due to the unique
and triumphant role of chance." (`L'Evolution du vivant' (The Evolution of
Living Organisms].)
In view of the fact that J. Monod received the Nobel Prize for Medicine, it
behoves us to ask the following question: How is it possible for such an eminent
scientist to put forward a theory such as this? The answer is quickly found: It
lies in a doctrinal system that rests .on a postulate that its author calls "the
postulate of the objectivity of nature... the systematic refusal to admit that
any interpretation of phenomena cast in terms of a `final cause' meaning plan
can lead to a `true' knowledge... While the organism observes the physical laws,
it also surpasses them, thus devoting itself entirely to the pursuit and
realization of its own plan..." This means that henceforth only those factors
that add new possibilities to the organism will be acceptable... We must also
show our admiration for the "miraculous efficiency in the performances of living
beings, ranging from bacteria to man..." The ideological ulterior motive is
patently obvious: It consists in the refusal to accept the existence of any
organisation in nature, and it leaves room only for individual `performances.'
In referring to the accidental alterations in the genes of living organisms and
their influence on the evolution of .living beings, J. Monod employs terms that
do not even allow us to think that his personal view might one day be subject to
revision: "We say that these alterations are accidental, that they take place by
chance. Since they constitute the only source of possible modifications in the
genetic code, which is itself the only repository of the organism's hereditary
structures, it must necessarily follow that chance, and only chance is the
source of any new development or creation in the biosphere. Pure chance, and
only chance freedom, blind but absolute the very root of the edifice we call
evolution: This central concept of modern biology is no longer a mere hypothesis
among other possible or conceivable hypotheses. It is the only conceivable
hypothesis, the only one compatible with facts acquired through observation and
experimentation. There is no reason to suppose (or to hope) that our concepts on
this point should or even can be revised."
In fact, however, the concept of `pure chance', `chance and only chance',
`freedom, blind but absolute the very root of... evolution' has received some
hard knocks from P. P. Grasse.1n `L'Evolution du vivant' [The Evolution of
Living Organisms], the eminent naturalist indicates that the problem of the
transfer of information within the cell could be much more complex that J. Monod
had foreseen when he stated that it was inconceivable henceforth to approach the
problem from any angle other his (i.e. Monod's) own point of view.
Let us first stress the fact that in the genes, as we shall see further on,
D.N.A. (deoxyribonucleic acid) is the basic chemical material or vehicle for
biological information. The information is transferred to the cellular cytoplasm
by a different substance, R.N.A. (ribonucleic acid). In Monod's theory, the
transfer of information is always referred to in terms of a flow from the D.N.A.
toward the R.N.A., and never in the reverse direction. In actual fact, however,
the unexpected and the unforeseen can indeed occur.
The following is the objection presented in `L'Evolution du vivant' (The
Evolution of Living Organisms):
"The dogma of the immutability of D.N.A., which is always presented as the
unique keeper and distributor of biological information destined to flow in one
direction only, has been put forward by eminent biochemists (Watson, Crick,
etc.) and geneticists (Jacob, Monod, etc.) Three years ago, in 1970, J. Monod
made the following statement on the subject in 'Le Hasard et la Necessite'
[Chance and Necessity], pp. 124 125: "It has never been observed, nor is it even
conceivable, that information is ever transferred in the reverse direction..."
P: P. Grasses objection continues in the following terms:
"The ink of these lines was hardly dry when the denial came, sharp and
incontrovertible. The logic of living things, which, by the way, was the logic
of the said biologist and not of nature, was totally overturned and the fine
edifice deeply flawed.
"The discovery of enzymes able to use viral R.N.A. as a matrix for the synthesis
of D.N.A. is regarded as a revolution in molecular biology.
"It is also considered", writes P: P. Grasse in a footnote, "to be the most
important discovery concerning the role of viruses in the formation of cancers.
Several R.N.A. viruses create D.N.A. replicas that are carcinogenic."
Further on, P: P. Grasse outlines the new contributions made by studies
conducted before (1964), during (1970) and after (1971 and 1972) the publication
of J. Monod's work. P. P. Grasse then draws the following conclusion:
"The studies outlined above show that a mechanism exists which, in certain
circumstances, supplies information that comes from outside the organism and
integrates it into the D.N.A. of the genetic code. For an evolutionist, this
fact is of immense importance."
The dogma of necessity put forward by J. Monod is a long way from explaining why
the organisms the zoologists call .`stock forms', which are the great ancestors
of today's types, have survived down to the present day and even live side by
side with the modern forms descended from them. The same may be said of the
unicellular organisms that still survive today, or even of older members of the
living world; such as bacteria: How can their survival be explained?
In order to support his theory of the `miraculous efficiency in the performances
of living beings', J. Monod records in his book the following story (which is
not based on any palaeontologic data whatsoever)
"The reason the tetrapod vertebrates appeared and were able to develop into the
extraordinary range of animals that we know as the amphibians, the reptiles, the
birds and the mammals, is that a primitive fish originally `chose' to explore
the dry land. There, however, it was only able to move about by leaping
awkwardly. ('Le Hasard et la Necessite' [Chance and Necessity], pp. 142 143."
P. P. Grasse concludes with the following remarks on the above statement
"What makes us particularly unwilling to accept the story of the little fish the
`Magellan of evolution' is the fact that the boleophthalmidae and
periophthalmidae (mud skippers) perform this very `experiment'. They scuttle
across the mud, climb the roots of mangrove trees, and raise themselves on their
pectoral fins, just as if the fins were short limbs. They have lived in this way
for millions of years, and although they never stop leaping about awkwardly or
not their fins insist ow remaining as they are, rather than transforming
themselves into limbs. These animals really are not very understanding."
Now that we have reviewed the explanatory theories of Antiquity and have shown
that more recent theories such as Darwinism, or the concept of chance and.
necessity are unacceptable, it is time to try and find our way through highly
complex scientific discoveries toward a clearer view of the problem. In several
instances, we have indeed already touched on some of these discoveries in order
to ensure a better understanding of the subject at hand, but if we are to arrive
at a more accurate idea of the causes that engendered the sequence of events
whose broad outlines we know already, we must enter into detail. This means
knowing more about the organization of the cell, and in particular the role of
the genes contained in the chromosomes. It was indeed the events that took place
within the cell that determined the progression of changes that as a whole
constituted evolution.
The following account of facts concerning the cell may perhaps seem a little
complex to some, while to others, who already know something of the subject, it
may seem over simplified and in need of more detailed information. I would ask
the former to try and grasp the data described, for they will be of help in
understanding what is to follow, and I entreat the latter to refer to the
publications I shall cite, in which they will find facts that complement my own.
Specialists in molecular biology, genetics and the study of chromosomes have
provided information on cellular functions and heredity that is extremely useful
in interpreting phenomena connected with evolution. The present work is. not
intended to provide an exhaustive study of the question; those wishing to
consult a bibliography on these subjects are advised to turn to the three
excellent articles in the Encyclopaedia Universalis contributed respectively by
P. Kourilsky, P. L'Heritier, and, for the study of chromosomes, M. Picard and J.
de Grouchy. I shall moreover be using many of their data and ideas in the
following section.
Essential Data Concerning the Biochemical Organization of the Cell
Chemical changes are constantly taking place within each and every cell. The
living matter contained in the cell is constantly renewed, and the cells renew
themselves by division within the organs, some of which such as the blood
possess a very marked capacity for self-renewal. In this context, the
reproductive cells should also be mentioned, which ensure the perpetuation of
the species.
In order for all these functions to continue, constant exchanges of matter and
energy with the surrounding environment must take place, resulting in the
production of macromolecules in the cell from simpler chemical elements. For
this to happen, the two components that are to combine must be present, there
must also be what are called catalysts, agents that have the property of acting
in infinitely small quantities to trigger the chemical reaction but which remain
unchanged once the reaction has taken place. Each catalyst is specific to the
reaction required. The production of protein in living matter, which results
from the' synthesis of simpler components, calls for the intervention of
catalysts which in this case are enzymes, each enzyme containing the unique
property of provoking the synthesis of a particular protein.
In their turn, the enzymes must be produced, and every cell possesses a system
for this purpose. The basic element of this system is a proteinic macromolecule
of tremendous complexity, called desoxyribonucleic acid (D.N.A.) The other
chemical components `hook onto' this basic substance, and with varying degrees
of complexity ensure the production of the enzymes that are to provoke the
proteinic syntheses required for life to exist..
In the simplest living organisms, D.N.A. is in direct contact with the substance
of the cell, the cytoplasm: An example of this is the bacteria, which do not
contain a nucleus. In other, more organized animal and vegetal cells, however,
the D.N.A. is located inside the nucleus of the cell within the chromosomes.
This means that it only intervenes indirectly in the process of synthesizing
living matter: It simply acts as the keeper of all the data (which taken
together constitute a parcel of information) required by the reactions, using
the intermediary of `messengers' that take copies from it (the D.N.A.) and carry
them to other parts of the cytoplasm, such as the ribosomes. The `messages' are
transmitted via ribonucleic acid, or R.N.A.
The message transferred from the nucleus to the cellular cytoplasm via R.N.A.
does not arrive directly however. The messenger R.N.A. in fact operates with the
help of a second R.N.A., a transfer R.N.A., which is effective in transmitting
the message, after which the messenger R.N.A. is destroyed. This detail
indicates the complexity of the communications system, which is in fact far more
complicated than it appears in this simplified outline, for the message is
actually transmitted in code...
Thus we begin to gain an idea of the countless interrelations that exist within
the cell, complete with its central command `headquarters', its messengers, arid
its intermediary organs, which play a part in the renewal of living matter.
Another important point is that the central command addresses its orders to
specific messengers in order to trigger the vast number of chemical syntheses
that condition an infinite variety of tasks to be performed. We are therefore in
the presence of an organized system that is of considerable functional size,
even though its volume is very tiny indeed. It is a system that conditions all
the activities of the cell; including its reproduction, which is how it comes to
play its part in heredity and thereby in evolution.
Every cell contains D.N.A. chains: In the case of bacteria, whose dimensions are
measured in l/ 1,000 of a millimetre, D.N.A. forms a tape whose length is
measured in millimetres. The tape is therefore quite short in this instance,
although in the case of Escherichia Coli, it has been calculated to be roughly
5,000 times longer than the maximum dimension of the bacteria in question. A
length of one millimetre is quite considerable in molecular terms, and on one
millimetre of D.N.A. tape are placed an infinite number of complex chemical
components, each of which conditions every single function of the bacteria: In
the case of man, for one single cell, the D.N.A. tape is long enough to be
counted in metres. As for the total length of D.N.A. tape contained in a human
being, it is greater than the distance separating the earth from the sun (P:
Kourilsky.)
The D.N.A. tapes, which measure over one metre in length for each cell, are the
keepers of the hereditary characteristics transmitted to us by our parents. They
convey alt the information that each and every cell in our body can use. As the
life of the embryo progresses, the cells become differentiated, acquiring
special functions and constituting all our organs in accordance with commands
issued by the genes. This entire system is miniaturized to an extreme degree; a
D.N.A. tape that is over one metre long is infinitely thin, its thickness being
measured in angstroms (one ten millionth of a millimetre.)
D.N.A. has a spiral structure in the shape of a double helix, one tape being
twisted around the other. Specialists in molecular biology have compared it to a
photograph accompanied by its negative. When a replica of the tape is produced
during cellular division, the two chains separate and each chain serves as a
mould for the production of a complementary, chain; exactly as the negative of a
photograph provides us with a positive print and vice versa. Thus we arrive at
two copies that are identical to the original, providing nothing has gone wrong
during processing.
The system's capacity for production and the diversity of the end result are
quite considerable. Bacteria such as Escherichia Coli can synthesize as many as
3,000 different, kinds of proteins. Over half of these have been identified.
Human cells contain a thousand times more D.N.A. than Escherichia Coli. Thus we
see the immense capacity of cells in higher organisms to produce extremely
diversified living substances: The list of proteins that can be synthesized in
this way is far from complete.
It is important to note the fantastic manner in which the D.N.A. tape grows
longer and longer as it passes from the cells of primitive organisms to the
higher organisms: At the bottom of the scale it is one millimetre long, but when
it reaches man, it is over one metre long (P. Kourilsky.) Later on, we shall see
that we may speak of an increase in the genes that corresponds, to the growing
complexity in the functions and structure of all living beings. The list of the
genes is no more complete, however, than that of the cellular proteins. The
implication inherent in these observations is that evolution must have been
intimately linked with the acquisition of new genes, which was henceforth to be
its sine qua non. The quantity of information recorded continued gradually to
increase over the course of time. .
The above information concerning the length of the tape on which the genes have
been placed seems to be more meaningful than the weight of the D.N.A. contained
in each cell. In P. P. Grasses book, `L'Evolution du vivant' [The Evolution of
Living Organisms], figures are provided relative to the weight of D.N.A. in the
cells of living beings located at a more or less high level in the scale of
structures. The weight of D.N.A. varies considerably from one species to
another, but without any apparent connection with the degree of evolution. This
does not seem to contradict what has been said above, however, for there is not
just one D.N.A. but several D.N.A.'s whose molecular weight fluctuates
according to the source from which it was extracted (thymus, wheat germ,
bacteria, etc.), the proportion ranging from one to several hundred (M. Privat
de Garilhe.) The chemical complexity depends on the number of elements held by
the tape. For example, the D.N.A. of Bacillus subtilis has a molecular mass of
at least 230 million, while the D.N.A. of herpetic virus has a mass on the order
of 100 million, and the mass of the single stranded D.N.A.. of bacteriophage is
some 1,600,000 (M. Privat de Garilhe.) For a simple body, such as water, which
is composed of two atoms of hydrogen and one of oxygen, the molecular weight is
18, the figures representing the degree of chemical complexity: A fact that
needs to be kept in mind.
The above comments concerning, D.N.A. contain reservations, for it is obviously
not possible to use a regular balance to weigh D.N.A. (the scale of measurement
is in this case counted in billionths of a milligram.) These estimations are
based on our knowledge of the simplest D.N.A. (simplest from a chemical point of
view), corrected by extrapolations derived from measuring the length of
molecules with the aid of an electron microscope. The figures are subject to
revision, and so are the conclusions we may draw from them. These observations
are presented simply to give an idea of the complexity of the organization in
question. They illustrate the notion that in order to grasp what evolution
means, one must take account of ultra microscopic studies of the cell and of
data provided by molecular biology, both of which have considerably increased
our knowledge. Sometimes, however, we encounter contradictions on points that
some people consider .to be of little importance, while others regard them as
highly significant. There are certain currently accepted ideas that will be
subject to revision in the future. The fact remains however, that science has
accumulated a sufficient number of established facts for certain general
concepts to emerge both clearly and logically from the data acquired by cellular
biology.
The Chromosomes
In describing the extraordinary biochemical complex we call the cell, we have so
far only briefly mentioned the role D.N.A. plays in retaining hereditary
characteristics, among its many other functions. As we have seen, in the case of
the most primitive unicellular beings, such as the bacteria, only one D.N.A.
tape is present: There is no nucleus. In the case of cellular organisms
containing a more elaborate structure however, the nucleus appears, in which the
chromosomes are concentrated: It is in the chromosomes that we find the genes.
Before proceeding, however, to an analysis of the role played by the genes
(especially in evolution), we must refresh our memory of certain ideas
concerning the chromosomes.
Their very name is a direct reference to one of their characteristics: The
reason Waldeyer gave them this name in 1888 was that he had noticed how these
differentiated elements within the nucleus could be stained with colourings the
moment the cell began to divide. In organisms that possess a sexual reproductive
system, the chromosomes are arranged in identical pairs: This distribution is
extremely important because it maintains the number of chromosomes always the
same in the same species during the reproductive process. When it arrives at
maturity, each cell whether spermatozoon or ovule possesses only half of the
chromosomes of the species. As soon as the two reproductive cells unite, the
even number of chromosomes is re established (46 in the case of man.)
One of the chromosomes has a role to play in determining sex; it belongs to the
male. The following is an outline of how the process works: The female possesses
a pair of chromosomes that are arbitrarily designated as XX; the male possesses
another pair designated XY. Since the number of chromosomes is reduced (meiosis)
during the formation of reproductive cells, the spermatozoa are divided into two
groups. One group contains X and the other Y. If the X ovule is fertilized by a
spermatozoon carrying an X a female (XX) will be formed. If it is fertilized by
a Y spermatozoon, the result will be a male (XY.)
The distribution of X and Y factors in the spermatozoa is almost exactly equal,
which is why the number of girls and boys born is practically the same.
Nevertheless, if the spermatozoa of the future father were successfully
separated into two groups and the woman artificially inseminated with one of the
groups, a couple would be able to decide whether they wanted a boy or a girl.
This is not at all a utopian vision, for the `manipulation' of human spermatozoa
is now sufficiently advanced for a project such as this to become a reality:
with the consequences that such a practice would entail, as may well be
imagined. Fortunately however, human reproduction has so far continued without
factors such as the above intervening in the distribution of sex the balance has
been maintained by nature.
Chromosomes are composed of D.N.A., R.N.A. and various proteins. The D.N.A.
carries the genes; these are not subject to renewal, contrary to the other
components of the cell. D.N.A. can only be renewed when the cells divide. The
quantity of R.N.A. varies from one cell to another and from one moment to
another. In performing its role as messenger carrying the information contained
in the genes, R.N.A. is constantly being renewed in the chromosomes; it
constitutes a, witness to the activities of the genes and ceases to be produced
when the genes have no message to transmit.
Irregularities in the chromosomes can produce extremely serious consequences;
spontaneous abortion (30% of such cases are due to failures in the regular
division of the chromosomes), and various illnesses that occur with differing
degrees of frequency, the most well known of which is Mongolism (trisomy 21, an
illness that affects roughly one child in 700.) Modifications such as these
either result in the death of the embryo or the birth of severely deformed
individuals. Over and above this however, living organisms are able to change
during the course of reproduction, even within the framework of a reproductive
pattern that tends to conform to the model provided by the individual's
forebears. The classic experiments carried out on vegetals by the Czech monk
Gregor Mendel in the mid nineteenth century (which did not become famous until
after his death) provide theoretical support to the research undertaken at the
beginning of the twentieth century: They led to the discovery of the genes and
their localization in the chromosomes.
The Genes
Today, it is an established fact that the genes are segments of D.N.A.
molecules. Through the action of the D.N.A., the process of which has already
been outlined above, they command the renewal of the proteinic molecules that
constitute the living matter of the cell. This biochemical activity modifies the
properties of the molecules in the cell, thus influencing the way the cell
functions as well as the production of specific structures which allow the cells
to play clearly defined roles. From this point of view, one might say that the
gene is the smallest part of the D.N.A. molecule capable of inducing a permanent
characteristic.
While the basic idea is admitted that the more complex the structure of an
animal, the more likely it is to possess a larger quantity of genes, specialists
in genetics are not in agreement on the number of genes involved. When they lead
to mutations; the genes are the objects of close study. In the case of the
drosophila, a fly which, from this point of view, particularly lends itself to
laboratory study, the number of genes counted is quite large: anything from
5,000 to 15,000! How many genes does man contain? No one really knows
[Estimates range from 100,000 to 1,000,000;
lower figures have also been suggested (30,000?)] . Besides,
the relationship between the number of features and the quantity of genes is not
at all clear. Some observers claim that a specific enzyme corresponds to each
gene, but a single enzyme may in fact give birth to several features.
The genes are responsible for may different functions. From this we may deduce
that the primordial functions that characterize a phylum depend on certain
genes, which have been operating, as it were, since the very beginnings of the
phylum in question. As evolution progressed, however, and one after another the
class, order, family, genus and species appeared, the genes intervened
successively and specifically for each major characteristic. The interventions
occurred at more and more recent periods in time, and they were perfectly
coordinated chronologically; it is to them that living beings owe their form.
Zoologists have many questions to ask on this subject. In `L'Evolution du
vivant' [The Evolution of Living Organisms], P: P. Grasse raises some extremely
important points, as follows:
| D.N.A. is just not present in the chromosomes; it is also active in the
mitochondria and other differentiated cellular elements. But what is the role of
this extra nuclear D.N.A.?
|
| The hormones play a part in triggering genetic activity. "A constant flow of
information streams from the nuclear D.N.A., while another floods toward it,
thus is setting it into action. Mutual communications between the cytoplasm and
the chromosomes, and vice versa, are a constant necessity" (P. P. Grasse.) He
goes on to cite experiments proving the influence of the cytoplasm on the
chromosomes. As we have already seen above, in P: P. Grasses criticism of J.
Monod's theory (according to which information could only flow toward the D.N.A.),
the dogma. of 'a one way stream of information has today been completely
disproven. |
All of the observations quoted above lead us to suppose that environment has an
influence ou the genes, which in their turn modify structures. P: P. Grasse
gives examples taken from the vegetable kingdom and concludes that: "The rule
stating that a gene will always determine the same characteristic unless it is
the subject of a mutation is too rigid." In all likelihood, "the gene emits the
same information, but the substances replying to its messages react in different
ways according to circumstances." All these comments indicate the fantastic
complexity of the system and the suggested importance of multiple interactions.
We have come a long way from the `freedom, blind but absolute' put forward in
the theory that attempts to explain everything in terms of `chance'.
The Role of the Genes in Evolution. Mutations
In the light of the data described above, how can we approach the role of the
genes in evolution? Simply expressed, there are two radically different ways of
tackling the problem: the geneticists employ the first. It is based on the
observation of present day facts; for example, calculations of genetic
variations in populations that exist today, from which are drawn explanatory
theories. Zoologists and palaeontologists use the second method. It involves the
examination of material from the past, data to which the first group do not
attach the same importance. In the survey that is to follow, we shall see that
the opposition of the two methods has repercussions on the concepts of evolution
entertained by the two groups.
In view of what we have already said about the infinite complexity of the
chemical structure of the genes, and in view of the manner in which copies are
produced during cellular division, it is perfectly possible to suppose that the
slightest modification in the structure of the D.N.A. molecule may affect the
cell concerned and all those engendered by it. This is indeed the case when the
modification affects the male and female cells responsible for reproduction
(germinal cells): It causes an alteration in the genetic code. In such
conditions, a new characteristic appears in the individual, which is passed on
to its descendants: This constitutes a mutation, and the phenomenon is known as
mutagenesis. It affects animals and vegetals alike, the most primitive life
forms as well as those with a more complex organization (i.e. those containing a
nucleus.) In the case of primitive forms, the mutation affects the D.N.A.
present in the cytoplasm (bacteria are an example of this), in the case of more
complex forms, it influences the chromosomes held by the D.N.A. in the nucleus.
The reason the mutation is considered to be fortuitous is that it is totally
unpredictable, both in terms of the moment it will strike and also the place in
which it will affect the D.N.A. molecule.
The impact the mutation has on the individual may be so great that the form
concerned cannot survive the mutagenesis (in which case the mutation is said to
affect lethal genes); on the other hand, the phenomenon may induce minor
modifications which may prove to be recessive over the following generations:
In this way, on the D.'N.A. tape of human cells, which is over one metre long,
tiny genetic alterations are present which provide the individual with the
characteristics that make him different from other people. It is these
alterations that cause him more or less to resemble his parents or grandparents,
and which even pass down the generations distinctive family features, such as
the nose typical of the Bourbon kings of France. Sometimes, very serious
phenomena can occur, such as illnesses connected with sex which affect the
female X chromosome: A case in point is haemophilia, which mainly affects males,
even though it is transmitted by females who remain immune to the disease. The
male descendants of Queen Victoria of England suffered from this illness. Apart
from these basically pathological mutations, most minor mutations tend to be
recessive.
In view of the above, the question of evolution might at first glance seem
fairly simple: The phenomenon of mutagenesis could tie seen to account for all
the hereditary variations which have accumulated over successive generations,
thereby causing the evolution of living beings. There are a number of
geneticists who subscribe to this theory. What is difficult to accept, however,
is that in order for this theory to be valid, the mutations would have had to
occur in a chronologically perfect order at exactly the right moment in time to
arrive at the addition or subtraction of organs, or to effect a change of some
kind in certain functions. It is perfectly clear, however, that these mutations
essentially occur in a disorderly fashion. At this point, the geneticists who
put forward hypotheses founded on calculations concerning present day
populations and who claim to have found an answer in this, part company from
those who study the events of the past. The latter have perfect confidence in
the findings of the former, as regards the properties of the genes, but they
claim to see many shortcomings in theories that account for the inscription on
the D.N.A. tape of new data that will become hereditary in the course of time.
The second group does indeed seem to be infinitely more exacting than. the first
about the demonstrative value of certain perfectly proven facts concerning the
genes.
First of all, however, the geneticists would have to arrive at a figure for the
possible number of spontaneous mutations: So far, this figure has not been
found. For one gene over an interval separating two generations, the estimated
number is 1 % 10,000 (P. L'Heritier.) There are also a number of mutations that
are neutral from the point of view of evolution. They form the source of
individual characteristics, but they do not go beyond the framework of the
species, and the individual thus retains all the attributes of that species. "We
are a long way from the billions of billions of `usable' variations mentioned by
certain geneticists. The so called usable variations are far fewer in number, a
fact which renders even more problematic the idea of a `good' mutation occurring
at the right moment" (P. P. Grasse.) We should not confuse the process of
fortuitous mutation, which is responsible for the personal characteristics of
the individual, with the active part played by mutations as the prime force
behind the process of evolution.
The idea of evolution signifies progressive transformations on a very large
scale. For example, the evolution of insects affected their entire organism in
very strict order. The transformation of organs took place slowly but steadily
over successive stages for example, it took the mammals 80 million years to lose
their reptilian features and in an order that is incompatible with the arrival
of random mutations.
In addition to the facts noted above, which result from pale-ontological
investigation, genetic research provides us with data based on the most
primitive organisms living today. These. are the bacteria, an easy subject of
study because they reproduce within the space of twenty minutes. It is thus
possible to follow the progress of thousands of generations, among which
mutations are, found in the D.N.A. molecule. But what is the practical result of
these mutations? Small scale variations: The species remains the same, as it has
done for hundreds of millions of years! As for the transition from the bacteria
or the blue algae to organisms containing a cellular structure with a nucleus,
an event that may well have occurred one billion years ago, it is reasonable to
suppose that environmental conditions were very different from those of today.
Because of this, it is difficult to imagine that the mutations observed in
today's bacteria are exactly the same as those produced in past ages.
The same mystery surrounds plants and animals that have not evolved at all in
millions of years, even though they may have undergone fortuitous mutations. In
this context, zoologists, cite the case of the common cockroach, which; as far
as they can tell, has hardly evolved at all since the primary era. The same
applies to the `pan chronic' species, thus named because they have survived
through the ages without any change, such as the opossum, certain limuli (marine
insects with gills, commonly called king crabs) and various vegetals, none of
which have been affected by mutations.
Objections have been raised on the above point, for certain observers maintain
that panchronic species survive unchanged because they live in confined
environments where conditions are not subject to much variation (for example,
animals living in caves or in the depths of the sea.). While this may hold true
for certain species living in such environments, it is not easily accepted by
anyone who has travelled and has seen cockroaches present in many different
parts of .the world.
Other Points Which Need to Be Explained
It is very difficult to say whether the location of the genes on the helix
shaped D.N.A. tapes at the level of the chromosomes has any effect on the
properties of the genes. Experiments have enabled scientists to separate and
reunite fragments, even from one chromosome to another, but they have given
positive and negative results that do not lead 'to any conclusions. As far as
our own origins are concerned, the normal position of certain genes on human
chromosomes is no more conclusive than the above.
It is possible for the number of chromosomes within a single species to vary: We
find this in certain small nocturnal rodents (jerboas), which, in Senegal, have
varying numbers of chromosomes
One group counts thirty seven for the males and thirty six for the females;
another group possesses twenty Three for the males and twenty two . for the
females. Nevertheless, the two groups are identical, displaying the same genes,
but without reproducing between each other.
We have good reason to suppose that among the genes of today's living beings;
the genes that once played an active role in the evolution of their species are
still present. The existence, for example, of rudimentary organs that constitute
relics of what were once fully developed organs indicates that the corresponding
gene has survived down to the present day. This does not mean; however, that it
is able to induce the formation of the entire organ (such is the case of the
equidae, and of the four winged drosophilae whose special feature, represents
something of a monstrosity.) We may well ask whether there is a repressive
genetic system, which phases out the ancestral genes that generate certain
characteristics in special cases, for paleontological studies have not indicated
a possible re-emergence of vanished organs.
Even before our knowledge of the genes enabled us to envisage the creation of
hybrid forms by crossing two different species or to attempt other kinds of
chromosomic manipulations, observations indicated that in the case of vertain
vegetals, it was possible to arrive at. a new species through interbreeding. In
1928, Karpechenko created the cabbage radish, a form that possesses the
chromosomes of both vegetals. Most of these newly formed vegetals are infertile,
but there have been a few examples whose seeds contained a double number of
chromosomes and which were indeed fertile, although only within the limits of
this new species. While it is possible to induce the doubling of the chromosomes
in certain vegetals, the same does not apply in the animal kingdom. There can be
no hybridisation between two lineages; zoology and palaeontology do not provide
a single example of this.
Genes and Regeneration
Examples of regeneration indicate beyond a shadow of a doubt the extraordinary
capacity the genes possess for triggering the growth of new tissue after major
amputations and even following the division of a body into several segments,
such. as we find in certain species.
In our discussion of regeneration, however, we shall not enter into detail on
the subject of the tremendous capacity that certain organs in the mammals (man
included) contain for development after an amputation: The liver is just one
example among many of an organ which is perfectly able to regenerate, and the
intestine is another. In the case of the latter, the mucosa is produced without
difficulty to ensure the healing of a wound after the two segments have been
surgically stitched together.
What concerns us here is regeneration that goes beyond the scope of the organs.
In the case of certain animals, it affects localized segments of the body,
which, when amputated, provoke the renewed development of the section removed.
The triton is an example of this: Like other batrachians, when its muzzle;
crest, tail, limbs or even its eyes are removed, the part that has disappeared
is entirely reconstituted. The earthworm is another well known example of
regeneration: The anterior part of the worm containing the head will be replaced
providing it is not cut at a point too far behind a clearly defined section of
the body, and similarly the posterior part will reform providing the worm is not
sliced at a point too far forward.
Examples of total regeneration are present among the invertebrates. In certain
cases, the animal is entirely reformed from a single segment of the body any
segment. In animals that figure lower down on the scale of organization, there
are many common examples, such as the water hydra : The process of regeneration
reconstitutes a number of new hydra that is equal to the number of segments into
which the hydra has been cut. This animal also renews its tissues spontaneously
in the course of its life. The most spectacular reconstitutions, however, take
place in the bodies of the planarians and the nemertians. These are flat worms,
which possess a digestive tract. The planarian, which is anywhere between one
and two centimetres long, can be carved into three parts by two transversal
cuts, for example: Ten days later, three new worms will have formed. A
regenerative 'bud' grows in the section left exposed by cutting, and in that
bud, muscles, digestive and glandular tissues nerves, etc. begin to appear which
will gradually replace all the missing organs in each of the three sections,
brains and eyes included.
Even more extraordinary is the case of the nemertians; these are another variety
of worm measuring some 20 centimetres to one metre in length. Like the
planarians, the nemertians also regenerate, but they possess the added ability
to cut themselves into segments (autotomy), an ability which is. more highly
developed than in other species. Autotomy is a defence mechanism used by an
animal that is under attack. In such cases, the animal separates itself from the
part of its body that has been caught by its attacker (the lizard leaves behind
its tail, the crab jettisons its pincer) and that part subsequently reforms. The
nemertian goes further than this, however. As P. P. Grasse writes in his `Precis
de. biologie animale' (Handbook of Animal Biology), when the nemertian undergoes
a "brutal shock, whether chemical or mechanical, it spontaneously cuts itself
transversally into sections which subsequently constitute new, individuals.
Furthermore, when completely deprived of food, it is able to survive through an
extraordinary process of involution. Its cells devour each other, and the
organism gradually shrinks. Dawydoff has been able to obtain examples of Lineus
Lacteus measuring 100 µ [i.e. one tenth of a millimetre] and composed of one
dozen cells! P. P. Grasse does not state whether the tiny number of cells that
still remain are able to reconstitute an entire worm, but the performance. of
these animals remains all the same quite staggering.
However that may be, while the anatomy of the worm indicates regeneration
processes triggered by the remains of the differentiated cells contained in the
anterior part of a carved segment, it is not possible to talk of regeneration
from these same vestiges when they are located in the posterior extremity (i.e.
the tail end.) We are obliged to admit that throughout the body of the animal,
from one end to the other, various cells are distributed that have .a
specialized regenerative function. Such cells are called `neoblastic cells', and
they constitute a kind of `reserve pool' of embryonic cells, which by a process
of differentiation reconstitute all the tissues and organs.
What a remarkable wonder of organization this is! It is difficult to imagine the
wealth of information that must be recorded on the D.N.A. molecules in the genes
in order to arrive at such results at exactly the right moment, in other words
at the moment circumstances bring all the appropriate mechanisms into play (such
as the cutting of the worm into several distinct parts.) All these events take
place in perfect order, and, to and behold, ten days later the planarians have
reconstituted themselves into normal individuals again! The autotomy of the
nemertians is another marvel of organization, for these animals can divide
themselves into sections under the effect of a specific stimulus. The genes,
which govern all these perfectly coordinated actions (this cannot be repeated
often enough) within the cell and which set in motion the process of
reconstruction, are genes that under normal conditions lie dormant. Phenomena
such as these raise extremely complex genetic problems; they open the door to
the question of the normal existence of `inoperative' genes, or `adaptative'
genes, in other words genes that make adaptation possible.
Genes and Animal Behaviour
The behaviour of familiar animals and the often quite spectacular exhibition of
certain abilities shown by others has led many people to attribute to these
animals powers of reasoning that far exceed their real capabilities. Many
animals do indeed give the impression that they are able to think through a
certain situation and come to a decision, which causes them to act with apparent
logic. In fact however, a large number of animal activities are hereditary; the
extent of automatic behaviour varies according to the degree of structural
complexity of the species.
A particular outside situation can cause' a stimulus in the more highly
developed species, which the animal in question integrates into its' memory
bank', and which subsequently conditions its response. Some people think that
this capacity is very closely akin to human faculties, but we shall see later on
the very considerable difference between human behaviour and that of even the
most highly developed animals. The difficulty arises from the fact that we are
inclined to judge animals in terms of our own mental faculties, whereas we ought
to judge them in terms of the faculties of the animals themselves.
The beings that are lowest on the scale of the invertebrates are capable only of
automatism. A certain amount of information needed to induce and condition
animal reactions is kept in the D.N.A. molecules, part of the genetic code.
Chemical reactions continually occur as the environment changes: It is to these
that the animal owes its behaviour.
A further degree of complexity appears when 'the activity concerned is cyclical
or regular; interspersed with periods of rest. The building of nests by insects
is an example of this: We see the same complexity present in the automatic act
of stinging: The female mosquito invariably obeys an inner impulse when the
stimuli are present that provoke heat and humidity on the human skin, especially
when the mosquito smells the odour of butyric acid present in infinitely small
quantities on the skin's surface. Here again, it is a case of innate behaviour;
the appropriate information is registered in the genetic code of the species the
animal is simply obeying orders like a robot.
Nevertheless, some invertebrates are capable of conditioned reflexes. We should
bear in mind that as opposed to the unconditioned reflex where the involuntary
action results from a single stimulus, we are dealing here with a conditioned
reflex, which requires some `preparation', as it were, before it can take place.
At an initial stage, the real stimulus is associated with an accompanying
neutral stimulus. In .the second phase, the animal responds in the same way to
the neutral stimulus alone. Reflexes such as this are present in 'bees and
butterflies for example, where the animal is guided by the shape and colour of
the flowers from which it gathers nectar; in the case of the bees, scent also
plays a part. This is as far as the `learning process' of these insects actually
goes, however, for it is not possible to tame or train insects.
The vertebrates are the only animals capable of acquiring reflexes such as these
and of recording and making use of information from the outside. Mammals can be
trained; dogs are a particularly characteristic example, on account of their
ability to integrate into human society. Here again, however, innate behaviour
still persists, such as courting patterns, the preparation of various
habitations which often requires very complex techniques, the raising of young,
the marking out of territory for defence purposes, the search for food, sexual
relations, etc.
As the level of organization rises, innate behaviour persists, even though the
animal is able to alter its response according to the given situation. Even in
the case of the higher mammals, such as the primates, the automatic, invariable
response dictated by the genetic code merely diminishes; it does not disappear
completely. P. P. Grasse' provides two very important examples of this:
Chimpanzees that have not lived in a forest since the day they were born, when
set free, know exactly how to build a night shelter in the trees. They put
together a kind of habitation that is identical to the dwellings constructed by
chimpanzees that have lived all their lives in the natural environment of their
species. Similarly, gorillas are always terrified by the sight of snakes in
their native forests: The same reaction occurs in young gorillas faced by the
sight of a dead snake, even though they are seeing a snake for the very first
time. These are undoubtedly examples of innate behaviour: The animal is obliged
to react in a certain way because it possesses in its D.N.A. molecules the gene
or genes that induce the coded responses to the specific stimulus.
Perhaps one of the most spectacular examples of an animal capable of
`memorizing' or `stockpiling' the information contained in the genetic code is
the case of a bird native to Australia. The extraordinary migratory pattern of
this particular bird is described in a work by J. Hamburger entitled `La
Puissance et la Fragilite' (Power and Fragility)
"On May 27, 1955, a Japanese fisherman caught a bird which was marked with a
ring on March 14 of that same year on the Australian island of Babel. In that
part of the world, the bird is known as the `mutton bird' or `short tailed
shearwater.' The catch was the first of a series of discoveries leading to the
reconstitution of the immense tour that this migratory bird undertakes every
year. Its point of departure is the coast of Australia; from there, it flies
east into the Pacific, turns north along the coast of Japan until it reaches the
Bering Sea, where it rests for a while. After this halt, it sets off again, this
time toward the south, hugging the west coast of America until it reaches
California. From there it flies back across the Pacific to its starting point.
This annual voyage of some 15,000 miles in the shape of the figure 8 never
varies, either in terms of the route covered or the dates involved: The journey
lasts six months and always comes to an end during the 3rd. week in September on
the same island and in the same nest that the bird left six months previously.
What follows is even more curious: On their return, the birds clean their nests,
mate, and lay their single egg during the ten last days in October. Two months
later, the young chicks hatch out, grow rapidly, and at the age of three months
watch as their parents fly away on their enormous journey. Two weeks later,
around mid April, the young birds take wing in their turn. Without any guidance
on the way, they follow the exact same route described above. The implications
of this are clear: Within the material transmitting their hereditary
characteristics contained in the egg, these birds must possess all the
directions required for such a journey. While some people may argue that these
birds are guided by the sun and the stars, or by the winds prevailing along the
route covered by their round trip, such factors clearly do not account' for the
geographical and chronological precision of the voyage. There can be no doubt
that whether directly or indirectly, the instructions for this 15,000 toile
journey are recorded in the command giving chemical molecules located within the
nuclei of the cells of these birds.
How is it possible to imagine the colossal mass of coded information that must
of necessity be adapted to a host of different conditions, all of which take
account of the various environments through which the birds must pass alone and
unguided - from Australia to the Bering Sea and back again - while at the same time
respecting a staggeringly precise timetable? How can we even begin to conceive
of the fantastic number of orders that must be issued in the space of six
months, orders that inevitably change according to circumstances, especially as
the climate alters? Every possible contingency must be anticipated within the
total fund of information held by the D.N.A. One wonders how the programme
originally came to be written, and whether there is a being who knows the
answer.
In today's computer age, such questions of programming cannot fail to make us
think of some of man's own material achievements in recent years. We are filled
with admiration for the magnificent technological results obtained by the
American space shuttle which having completed its test flight, returned to earth
at the moment calculated in advance. As scientific observers have repeatedly
stressed, the launching of the shuttle, its orbiting around the earth, its
descent back to earth, and many other manoeuvres, were aided by powerful
computers working in coordination. The computers issued orders to the shuttle's
engines, and in certain instances rectified the original orders in accordance
with positions, which were themselves plotted by computer. In order for the
venture to succeed, split second timing was required for the recording of data,
the processing of information, and the issuing of commands; an ensemble of
operations that was far beyond any human capacity. Although piloted by two
spacemen, .the shuttle relied on pre-recorded information to complete each and
every manoeuvre. Our Australian `mutton bird' would have had as much difficulty
completing its lone voyage for the first time across unknown continents and seas
as the astronauts would have had in completing their mission, had it not been
for the back up supplied by information recorded in advance. In its genetic
inheritance, the `mutton bird' simply has to possess all the instructions
required for its six-month journey. Surely there is no one naive enough to
imagine that the space shuttle and all its computers could have been built and
fed with highly complex programmes by the effect of mere chance? Anyone who
thinks that has obviously lost touch with reality., In actual fact, the shuttle
is programmed by highly trained experts who supply all the information required
for its missions. Why should we not therefore accept the idea that the `mutton
bird' just as much as the space shuttle must of necessity be put in possession
of the information it requires in order to return to its point of departure?
This is the logical conclusion we must draw from our comparison with the
programmer.
Genetic Manipulations
Although this is a subject that affects man's future rather than his past, and
although genetic mutations are `experimental' and offer nothing in terms of the
origins of man, they must be mentioned here on account of the legitimate anxiety
they provoke.
The genes are responsible for each and every function of the cells. Some
scientists have had the idea of supplying the cells with new properties by
modifying the genes. In actual fact, they began by experimenting on organisms
with a structure that is even simpler than the cell, namely the bacteria. By
`grafting' various genes onto Colon Bacilli, they triggered the production of
certain therapeutic and nutritional substances; owing to the rapid reproduction
of bacteria, they were able to obtain very large quantities of these substances.
The experiment was particularly successful in the case of several hormones.
From this, it was suggested that experiments might be performed on more highly
developed animals with the unspoken idea of creating new characteristics by
`grafting' new genes or modifying existing genes. Some scientists have even
thought that, should these experiments prove successful, they might be applied
to human genetics, in order to `improve' man...
The above would imply a perfect familiarity with the genetic map of the D.N.A.
tape, which is not the case at all. We may therefore assume that experimental
successes of arty importance within the animal kingdom are not likely to occur
just yet. The extremely complex problems that remain to be solved would probably
protect humanity from experiments such as these, but we must fear the worst as
far as innovations deriving from human ingenuity are concerned: Man is capable
of the worst as well as the best.
In an instance of this kind, man's dominance overman could reach to absolutely
abominable extremes. The consequences of such practices, if they eves became
feasible, are chilling indeed, for it is not difficult to imagine the abuses
that would follow.
Nevertheless, these are precisely the practices currently being put forward by
certain scientists. E. O. Wilson and the socio-biologists, whose theories have
already been mentioned in connection with neo Darwinism, have used their
position as scientists to assume the right to organize human society in terms of
their own theories, relying on genetic manipulations which they euphemistically
label `genetic engineering.' In their published works, they outline the process
by which, in their view new human beings could be produced. For example, in
order to increase man's sense of family, what simpler solution would there be
than to contribute the corresponding gene found in certain gibbons? Among these
apes, there are certain individuals who are endowed with a distinctive
anatomical characteristic, which, more than in other apes of the same species,
displays this highly developed sense. All that would have to be done would be to
`graft' the characteristic onto man by means of the appropriate genetic supply.
Suppose we wanted to increase people's enthusiasm for work: The simple transfer
to us of the gene that conditions this function in worker bees would
automatically turn us into total `workaholics.'
The above examples of genetic manipulations, which were put forward by Wilson
and his followers, were reported at a round table conference on May 26, 1981 at
the, Palais de la Decouverte in Paris. On the same occasion, brilliant papers
were delivered on the subject by eminent scholars, among them P. Thuillier and
P: P. Grasse', while several of their colleagues commented on the extreme
seriousness of the proposed projects. It would indeed be most unwise to treat
lightly the proposals suggested above, for they are put forward by genuine
experts who declare that by virtue of their superior position as scientists,
they have the right to change their fellow men as and how they please, using
procedures over which they alone have jurisdiction. This new 'master race' of
scientists is also able to take advantage of the tremendous media coverage open
to their theories in the United States. During the round table conference at the Palais de la Decouverte, P. Thuillier noted that socio-biology was gradually
becoming institutionalised in France. It is indeed difficult at present to see
how the socio-biologists can arrive at a technique for `grafting' genes that are
not yet isolated. But if they were one day able to isolate these genes and
thereby realize projects, which put man in the same category as laboratory
animals, the abominable extremes at present feared would become a reality.
Let us not forget the extent of the scientific aberrations and contempt for men
that in the long run were caused by Darwinism.
The term `creative evolution' is not intended to carry any philosophical
connotation in the sense in which it is used here. It is not often employed by
modern scientists, as a way of describing evolution, perhaps because the
reference to `creation' might come as a shock to the true researcher for whom
the term suggests the idea of transcendence. In view of the facts described in
the preceding pages however, it seems to me that we are simply stating a
primordial truth when we use the term to qualify evolution in the animal
kingdom: Indeed, we must accept the facts as they are, for when taken as a
whole, evolution in the animal kingdom does not provide any possibility for a
return to more ancient forms; complex structures do not revert to a simpler
state. Quite the opposite happens in fact. Thus we are forced to take account of
new forms that develop in the course of time, forms which are non transitional,
and which contain new organs that condition new functions. We may therefore talk
of the creation of organisms that did not previously exist, either in terms of
forms or functions.
In the latter case, the example of the Australian `mutton bird' is extremely
revealing: Its migratory performances alone tell us that at a certain moment,
the information required for the bird to undertake its fantastic journey must
have been introduced into it's genetic code. The informational data specific to
the bird's organs must necessarily have been recorded in a genetic code that
contained the specifications for all birds, at a time therefore when the birds
were already in existence, i.e. after their emergence from a certain category of
reptiles, some 135 million years ago.
Evolution as we know it is quite obviously dependent on a process of successive
additions of information over the course of time. Scientists can argue ad
infinitum about the causes determining the fact, but they cannot get away from
the fact itself because it is patently obvious. Theories such as `random genetic
mutations' and the `necessity of natural selection' may represent a satisfactory
explanation of the past for some, but for others they are nothing more than
unacceptable or half-baked hypotheses. It is blindingly clear, however, that the
phenomena of evolution each had their beginnings marked by particular events.
When certain of today's theorists (who claim to have an explanation for
everything) are asked just where the point of departure or origin of genetic
information lies, they are at a loss for words. How could they fail to be? J.
Monod has already acknowledged this inability to explain in the passage quoted
earlier from his book 'Le Hasard et la Necessite' (Chance and Necessity): "The
major problem is the origin of the genetic code and the mechanism by which it is
expressed. Indeed, one cannot talk so much of a `problem' as of a genuine
enigma." We have started with an `enigma', passed on to `fortuitous mutations'
which modify structures, and ended up with the `necessity of natural selection',
and not one of these theories has told us anything. They have not explained how
highly organized matter came to be formed, complete with informational data to
control its functioning and reproduction; nor have they enlightened us as to the
complexity of the system which controls each and every aspect of the behaviour
of entire organisms, as in the cases mentioned above.
Once we begin with complete objectivity to sort through the various ideas
expressed on animal evolution by specialists from disciplines as disparate as
the natural sciences, palaeontology, molecular biology and genetics, the
discrepancies become very striking. If we continue to remain impartial, we shall
be forced to admit two facts: while there are palaeontologists who take account
of the data provided by the natural sciences, there are few specialists in
molecular biology or genetics who turn to zoology, botany or palaeontology to
support their theories. In contrast to this, there are highly experienced
specialists in the natural sciences, such as P. P. Grass6, who constantly refer
to the data supplied by chemistry and ultra-microscopic studies of the cell in
their interpretation of the salient features of evolution. I turn once again to
the data used by P. P. Grasse to uphold and spread his concept of evolution, in
which he tries to separate established fact from unproven speculation.
We have already examined the reasons why the theories of Lamarck and Darwin do
not provide an explanation for the genesis of the basic phyla, each of which
arrived at an organizational plan for an entire lineage. Fortuitous mutations do
not adequately account for the emergence of major variations: They cannot create
new forms with modifications that affect several organs in a coherent manner.
All of these events took place in very long stages; at the beginning, there
appeared the first signs of particular features, followed by a period of
accentuation of these phenomena, which was rounded off by a phase during which
events slowed down and the creation of new type's finally ground to a halt. At
the present time (`present' meaning at this point on a scale of millions of
years), we would appear to be in this final stage. As we shall see later on
however, in the case of man, evolution came to a halt much more recently.
All the major organizational types were laid down at a very early stage. From
the moment a type engendered certain forms that oriented themselves in a
particular direction, no new organizational types emerged from specialized
forms. "Creative evolution has its roots in prototype forms; without them, no
new types of organization can ever appear" (P. P: Grasse').
The last great wave of evolution in fact took place during the early stages of
the tertiary era with the emergence of the birds 135 million years ago. From
that time onward, the amplitude of the variations diminished, until there were
virtually none at all at the time man appeared. As for the causes of the
variations in the speed of the process and the halt in the creation of new
types, no one knows the answer.
At the cellular level, evolution raises questions, which can now be answered by
molecular biology and genetics. No new phenomenon can occur in the cell without
the intermediary of the D.N.A. molecule, which, by means of the R.N.A. molecule,
is responsible for the formation of a protein that constitutes the origin of a
chemical synthesis. For every important morphological variation, the D.N.A.
molecule must acquire a new gene, thus adding to its fund of chemically held
information, or modifications must occur in. a gene that already exists. P. P.
Grasse was the first to put forward the idea that evolution could be explained
by the creation of new genes. In his book, ‘L'Evolution du vivant' [The
Evolution of Living Organisms], he quotes the statements of the American
geneticist Ohno, who in 1970 said much the same thing. It has not of course been
possible to demonstrate the formation of new genes over the course of time.
Nevertheless, we shall see in a moment why it is unthinkable that this formation
did not take place.
The acquisition of new information by living organisms, is broadly outlined by
P. P. Grasse in the following passage:
"The responses to the stimuli conditioning evolution are recorded in the
individual's genetic inheritance; this is what makes adaptation possible.
Certain conditions must be present for these responses to be recorded. Now we
know for certain and this is a fact to bear in mind that evolution diminished,
as the living world grew older. It is vain to ask, however, why these responses
became more and more infrequent, for the present state of knowledge can provide
no answer. Perhaps one day, when molecular biology is more refined and precise,
we may find a reply to these questions.
"We do however possess certain facts which, while they may not solve the problem
of evolution, at least enable us to gain a better understanding of the phenomena
it entails, and thus help us direct our research into hitherto unexplored
regions.
"An animal would not be in a position to survive if it had no information about
its environment, taking the word in its widest sense. The sensory organs receive
messages and transmit them in modified form to the nervous centres where they
are interpreted and thereby trigger responses appropriate to outside stimuli.
Acting as the `computers' of the organism and capable of receiving various
programmes, the nervous centres function in accordance with the specific and
innate information that permanently controls their actions.
"The specific information lies within each cell, recorded on its D.N.A. tapes
and contained in the genetic code. It is the intelligence of the entire species;
which finds its material expression in an extremely miniaturized form. It is
also the intelligence of the lineage at a particular time `T' in evolution. The
information settles on the D.N.A. tape into which it is integrated and recorded
during the stages through which the successive species pass. It is the result of
a slow process of development, during which a balance was struck between the
living organism and its environment.
"Specific information is transmitted in the form of chemical signals emitted by
the segments or genes in the D.N.A.
"Nevertheless", as P: P. Grasse stresses, "the formation of new genes has not
been observed by a single biologist; and yet without that formation, evolution
becomes an inexplicable phenomenon."
P. P. Grasse completes his theory in the following manner:
"In our opinion, new information, which materializes and integrates itself
permanently into the genetic code in the form of sequences of nucleotids, can
only arise from preliminary intracel-sequences of reactions. It has nothing
whatsoever to do with mistakes in the copying process or anomalies in the D.N.A.:
It is in fact the result of an orderly development that takes place over
successive generations. The evolutionary process operates when very precise
conditions are present; for the moment, those conditions do not appear to arise
very often. The moving forces behind this remarkable process are most probably
stimuli received from outside, internal impulses, and the general responses of
the organism which affect it right down to the level of the molecule."
The main theories we have passed in review may be narrowed down to two
hypotheses: The theory of mutations resulting from `errors in the copying
process' of the genetic code, the product of chance, with the possible control
of corrective procedures such as natural selection or other factors; and the
theory of creative evolution, which cannot unfortunately be based on a
demonstration of the existence of new genes. Even though the material recording
of new information in the genes remains to be shown, there can be no doubt that
the concept of new data as the determining factor of evolution provides a
perfect explanation for the phenomena observed.
So which of the two theories do we choose?
- The theory, which relies on the basic role of chance, is untenable for the
reasons we have already discussed.
- The theory based on creative evolution via new information is perfectly
logical. Its validity is clearly illustrated by P: P. Grasse in his book `Precis
de biologie generate' (Handbook of General Biology)
:
"If we deny the formation of new genes, what we are in fact saying is that the
Amoeba or the Monera
[Author's Note: A primitive
unicellular organism, which, according to Haeckel, did not possess a nucleus.], as Haeckel would have expressed it, possessed all the
genes which, in the course of evolution, were distributed among the various
species in the animal kingdom.
"This mystical conception of the living world, in which everything is considered
to be preformed, comes as a shock to any biologist who sets great store by
reason and scientific precision. How can one seriously acknowledge that the most
primitive living being could genuinely and substantially have contained within
itself all the genes of the animal kingdom, or even the vegetable kingdom,
without thereby lapsing into tacit animism?
"The acquisition of genes is the absolute prerequisite for evolution. We cannot
avoid this possibility, for our whole comprehension of evolution and its inmost
mechanisms depends on it, and it alone."
Jean Rostand does not appear to have been perturbed by the term `creative
evolution'. This celebrated biologist has never made any secret of his
materialistic ideas: Let us therefore conclude the first part of the present
book with a quotation from him on the opposed theories of creative evolution,
and chance and necessity.
"I have only to watch a cricket leap or a dragonfly dart through the air, in
order to feel more akin to Pierre P. Grasse than to Jacques Monod."
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