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Origins of Darwinism
Darwin, according to the legend, had
pondered hard over this theory for several years before making it public.
Shortly after his return from a five-year-long voyage abroad H.M.S. Beagle in
1836, he had started writing his secret notebooks on “Transmutation of
Species”. He had come back with, what the legend describes, “an enormous
store of material from South America” where he had found fossils of extinct
armadillos that were similar but not identical to the living animals. In
Argentina he had seen species vary geographically; for example, the giant
ostriches (rheas) on the pampas that were replaced to the south in Patagonia by
much smaller species, both of which were akin to but different from the African
ostrich. He had also observed and had been disturbed by the fact that the birds
and tortoises of the Galapagos Islands off the western coast of Ecuador tended
to resemble species found on the nearby continent, while inhabitants of similar
neighbouring islands in the Galapagos had quite different animal populations.
But let us also note that according to
his own account, he had left England little disposed to question the literal
truth of Genesis and he had come back with little left of that belief. Thus,
when upon his return, Darwin learned that the finches he had brought from the
Galapagos belonged to different species, not merely different varieties, as he
had originally believed and that the mockingbirds were of three distinct species
and that the Galapagos tortoises represented at least two species and that, like
many of the specimens from the archipelago, they were native to the islands but
to neither of the American continents, his doubts about the fixity of species
quickly crystallized into a belief in transmutation.
Within a short span of a few months
after his return, March 1837 to be exact, he confided in his notebook that
species changed from one place to another or from one era to the next. In
October 1838, when Darwin read Thomas Malthus’ “An Essay on the Principle of
Population” in which Malthus argued that population growth is geometric, while
the food supply increases only arithmetically, and thus that population increase
is always checked by a limited food supply, Darwin hit on the exact term he had
been struggling for. Later, he noted in his Autobiography, that
“favourable variations would tend to be preserved, and unfavourable ones to be
destroyed...The
result of this would be the formation of new species. Here, then, I had at last
got a theory —the principle of Natural Selection—by which to work.”[1]
To be sure, this was not the first time
that someone had noted the savagery of the natural world, the brutality of
species against species; lions have always been devouring lambs. What Darwin saw was
competition
between individuals of a single species. He recognized that within a local
population the individual with, for example, the sharper beak, the longer horn,
or the brighter feather might have a better chance to survive and reproduce than
other individuals. And if such advantageous traits were passed on to new
generations, they would eventually be predominant in future populations. Darwin
thus shifted the focus of evolutionary analysis from between
to within
species. He saw natural selection as the mechanism by which advantageous
variations passed on to succeeding generations and by which the traits of
individuals that were less competitive gradually disappeared from populations.[2]
Darwin had realized that the data he had
collected during his voyage abroad H.M.S. Beagle and since his return fit so
well with the idea of natural selection. This realization, which was perhaps a
result of a fever-stimulated brain as much as it was the product of more than
thirty years of mulling over an impressive range of observations, produced The
Origin of Species by Means of Natural Selection[3]
which was to add a novel and transforming idea to the repository of concepts of
Origins that humanity had formulated.
It is interesting to note that Darwin
himself had initiated the tradition of providing a cursory “historical
background” to his theory by starting off with a passage from Aristotle’s Physicae
Auscultationes[4]
with a stinging remark (“but how little Aristotle fully comprehended the
principle, is shown by his remarks on the formation of the teeth”). Note that
this reference to Aristotle is immediately followed by a mention of the “first
author who in modern times has treated it in a scientific spirit”—Buffon who
is also dismissed with a cursory remark. Then Darwin goes on to state that
“Lamarck was the first man whose conclusions on the subject excited much
attention. This justly celebrated naturalist first published his views in
1801.”[5]
Between Aristotle (384-322) and Lamarck (1744-1829) lie two thousand years of
human endeavours to understand the enigma of creation! But this summary
rejection of two thousand years of history to understand the mysteries of the
origin of life is not specific to Darwin alone; it was characteristic of the
nineteenth century science, which was remarkable in gathering an unprecedented
amount of data about the natural world. But it suffered from the snobbery of
self-conceit.
A direct result of this historical
reductionism is that the contemporary discourse on Intelligent Design is simply
unintelligible to a vast majority of humanity. As a result, this discourse has
remained limited to a small part of the planet. This myopia, which not only
restricts but also distorts the very nature of the discourse, has serious
consequences for the very nature of inquiry.
It may be argued that those non-western
scientific traditions have nothing to add to the contemporary discourse; that
modern science is a universal phenomenon and that the parameters of the
discourse are entrenched in non-cultural, non-religious soil. But all of these
assumptions have been shown to arise from the same epistemological frame that
has produced the myopic vision we just described. It is illogical to assume that
the real nature of Creation would only become intelligible to us after centuries
of human existence just because we have refined our tools of measurements and
have been able to penetrate the vast uncharted realms of sea and space, which no
previous generation has done. It is illogical because here the extent of
quantification is taken as a measure of the knowledge of Reality. The knowledge
of Reality does not increase or decrease with quantification: a drop of water
can provide as much knowledge about the reality of water as an ocean.
The Historical Background
This was not a totally unfounded
conceit. After all, behind the nineteenth century science lay the unshakable
belief that reality is made of nothing but the physical world which can be
perceived, measured, explained and mathematized with the help of sciences. By
the time Darwin appeared on the scene, this idea, which has its origins in the
Cartesian dualism, had solidified into a firm belief. Already in the fifteenth
century, mathematics had regained its position as the queen of sciences. It was
this zeal for mathematics that enormously affected young Nicolaus Copernicus
(1473-1543) when he was a student at Bologna and the later, the triumph of his
astronomical theory added fuel to the process of mathematization of the physical
universe. Kepler (1571-1630) wavered between the transcendental Platonism and a
flattened universe made up of mathematical equations but Galileo (1564-1642) had
no qualms about turning his attention downward, to the forces which bring down
moving objects and to mechanics, which had already become a craze in the
fourteenth century when every European community was bent upon having gigantic
astronomical clocks. “No European community felt able to hold up its head
unless in its midst the planets wheeled in cycles and epicycles, while angels
trumpeted, cocks crew, and apostles, kings and prophets marched and
countermarched at the booming of the hours.”[6]
By the seventeenth century, a clockwork universe was very much in the final
stages of transforming the intellectual landscape of Europe, as Professor Smith
has noted in his perceptive[7]
Cosmos &
Transcendence. However, it was left to Descartes
(1596-1650) to articulate the signs of times. But “we need not attempt to
follow Descartes in his solitary meditations, wherein he sought to touch the
bedrock of human knowledge. Suffice it to say that he emerged from his garden
retreat fully convinced that the universe is precisely what it must in fact be,
if it is to submit to mechanical description.”[8]
A detailed discussion of the rise of a
mechanistic worldview would take us away from the topic at hand. But let us just
mention that the mechanical world thus perceived, constituted as it was entirely
of res extensa
(which, later, became Newtonian “matter”), had an independent entity,
matter, that was subjected to mechanical laws and everything else had to be
relegated to res cogitans, the
thinking substance. This Cartesian duality was not without its own problems as
Descartes himself knew and spent the rest of his life in attempts to extricate
himself from the web of his own postulates. He fluctuated a great deal,
sometimes being left with no recourse but to invoke Deity to solve philosophical
problems. Nevertheless, what he gave to the scientific world was a revolutionary
idea which, in the hands of subsequent English materialists, went through
further mutations until “by a curious reversal of Cartesian logic, the res
extensa gained precedence over the res cogitans, or as one
might almost say: the conjecture swallowed up the dream.”[9]
One of the most striking metaphors of
the seventeenth century—the century of “mechanical philosophy”—was the
clock but in general, the main thrust of the mechanical philosophy was to
explain everything in terms of matter and motion. Descartes’ main contribution
in rise of mechanical philosophy was his conception of the whole cosmos in terms
of matter and motion. In his cosmos, humans differed from animals because they
posses rational souls, had capacity to think rationally and articulate
intelligibly. In order to clearly differentiate humans from animilas, Descartes
tried to formulate their existence on a separate plane. He thought that animals
“have souls of an entirely different nature from ours... [The] fact is that
they have no intelligence at all.[10]
Thus in spite of the emerging mechanical
and materialist worldview, Kant (1724-1804) was to re-affirm at the end of the
eighteenth century that “as the single being upon earth that possesses
understanding, and, consequently, a capacity for setting before himself ends of
his deliberate choice, he [human being] is certainly titular lord of nature,
and, supposing we regard nature as a teleological system, he is born to be its
ultimate end.[11]
The eighteenth century was also a
century in which most naturalists were obsessed with the idea of finding the
“ultimate system” that would explain all variety. A young student of
medicine, Carl von Linné (1707-1778), better known as Carolus Linnaeus, had
undertaken an extensive expedition into northern Sweden to study the animal,
vegetable and mineral kingdoms. At the young age of 28, he published his Systema
Naturae (1735); this was followed by a stream of
other publications, the last one being Systema
Vegetabilium, published in 1774, four years before
his death.[12]
He spent the better part of his life teaching natural history at the University
of Uppsala in Sweden and inspired a whole generation of students who would
travel in other parts of the world to collect data which would feed into the
taxonomic systems conceived by their mentor. The whole nature was divided into
three kingdoms, each kingdom had successive classes, genera and species, all of
which were presented in the form of a table.
Linnaeus’ was a biblical cosmos. His
taxonomies were attempts to discover the order of God’s design, his tidy
tabular ordering of the taxonomic systems kept the three kingdoms of animals,
plants and vegetables in separate categories. His animal kingdom, limited as it
was to a small number, was ordered in a natural, rather than an artificial way:
Quadrupeds, Birds, Amphibia, Fish, Insects, Worms.[13]
His plant kingdom, likewise, was restricted to the flora of northern Europe and
he could classify plants on the basis of number of stamens and carpels in the
flowers. The number of stamens determined the classes (Monandria,
Diandria, Triandria, etc.) and the number of
carpels determined the orders (Monogynia,
Digynia, Trigynia, etc.) More importantly, note
that Linnaeus’ was atemporal world. As a firm believer in the Biblical account
of Creation, Linnaeus was looking for the Divine order, not creating a human
order. His obsession with order was also at work behind the redesigning of the
botanical gardens at Uppsala on the basis of his plant taxonomy. He sowed plants
of his taxa in separate beds, thereby reproducing the original plant creation.
In 1909, these Linnaeus’ gardens were restored to their eighteenth century
condition and visitors to Uppsala now have the opportunity to walk back into the
botanical plan of the world.
But this orderly and atemporal world was
increasingly being threatened within the life time of Linnaeus. In 1741, an
Uppsala student, Magnus Ziöberg, discovered a
plant which Linnaeus considered to be a hybrid. But according to his scheme,
hybrids were supposed to be sterile (like mules); this plant, now thought to
have been produced by a process of gene recombination (Peloria from Linaria),
was, however, fertile. This was a sort of crisis for Linnaeus whose orderly
world had proven to be less stable than he thought. The solution proposed by
Linnaeus was that God originally created the upper levels of the taxonomic
hierarchy but genera and species could be regarded as the ‘offsprings of
time’:
We may suppose God at the beginning to have
proceeded from simple to compound, from few to many; and therefore at the
beginning of vegetation to have created just so many different plants, as there
are natural orders. That He then so intermixed the plants of these orders
by their marriages with each other; that as many plants were produced as there
are now distinct genera. That Nature then intermixed these generic plants by
reciprocal marriages (which did not change the structure of the flower) and
multiplied them into all possible existing species; excluding however,
from the number of species the mule plants produced from these marriages, as
being barren.[14]
It is also pertinent to note that the
neo-Platonic doctrine of Great Chain of Being, which had gone through several
modifications at the hand of Muslim thinkers, was still alive in the eighteenth
century. G. L.L. de Buffon (1707-1788), the keeper of the Jardin du Roi (the
Royal Botanical Gardens) in Paris and the editor of a massive work on natural
history¾the
celebrated Histoire
Naturelle which appeared in forty-four volumes
between 1749-1804[15]
was one of the champions of this doctrine, though, he shocked many readers with
his bold claim that “the first thing that emerges from this thorough
examination of nature is something that is perhaps rather humbling for man; it
is that he must himself be ranked among the animals,” he wrote in the first
volume of the Histoire
Naturelle.[16]
Buffon believed that the systems like
the one proposed by Linnaeus in his Systema
Naturae were useless because there was an infinite
number of forms shading into one another. He insisted that the Classes, orders
and genera existed only in imagination. This anti-Aristotelian, nominalist[17]
position could be traced back to John Locke (1632-1704) and further, into the
medieval period.
But Buffon’s position went through
modifications over the course of years. By the time he published the fourth
volume of the Histoire
Naturelle in 1753, he was offering a precise
definition of the concept of species which was based on the phenomenon of
self-replication, rather than general similarities of forms. Note the stress in
this latter stance on functionality.
Species could be defined on the basis of functional observables.
Buffon was, however, aware of the
problems his theory raised. There was, for example, no way to explain the
appearance of fertile hybrids and the whole scheme was far less elegant and
orderly than the neat systems of Linnaeus. In 1766, when he published the
summary of the natural history of the quadrupeds, Buffon suggested that
environmental conditions might cause an initial group to split up into a set of
related but distinct species. Thus, it was possible for zebras and asses to
appear from a single stock (souche)
of horses. It is also important to recall that Buffon referred to this process
of splitting of a group into sub-groups as a process of “degeneration” and
though he had placed man in the first rank of the animal hierarchy of the Great
Chain of Being, Buffon still considered the gap between apes and man an
unbridgeable separation owing to the ability of human beings to articulate
rationally.
Linnaeus and Buffon thus present two
opposite trends of the eighteenth century views on the nature of species.
Linnaeus belonged to the Aristotelian tradition, Buffon to the neo-Platonic;
Linnaeus constructed orderly systems, Buffon aspired to place everything in the
Great Chain of Being, Linnaeus thought in terms of categories and systems. Both
were concerned with the outward aspects of the organisms and both were
interesting in descriptions, definitions, classifications and nomenclature. And
though Buffon dealt with geographical distribution and variation under
domestication, he was clearly not thinking in Darwinian terms. We have, thus, a
movement toward evolution, but not quite a Darwinian movement yet.
Thus behind Darwin’s bold assertion
lay two hundred years of scientific tradition which had seen the emergence of
such men as Galileo (1564-1642), Isaac Newton (1642-1727), Luigi Galvani
(1737-1798), Carl von Linné (1707-1778), better known as Linnaeus, Antoine
Lavoisier (1743-1794), William Herschel (1738-1822), powerful inventions like
the telescope and the steam engine and transforming discoveries like the
gravitational force and theories of planetary revolutions.
The point we wish to make is that the
nineteenth century had inherited the belief in the ability of science to
describe everything and Darwin was merely articulating what was already in the
air. In other words, the scientific data Darwin was trying to interpret was
interpreted in the backdrop of an emerging scientism[18]
and in an intellectual climate that was rapidly working to eradicate belief in a cosmos created
by God, a belief that had dominated the intellectual space of Europe for
centuries. Thus Darwin’s own firm belief in his discovery was strengthened by
the general intellectual trend of the age in which he lived, the age of
“scientific certainty”.
This is not to say that this emerging
scientism was unchecked. There were scores of dissenting voices that spoke
against these trends and attempted to check the flow. But they were drowned,
ignored or silenced. A case in point is that of William F. Warren, the first
president of Boston University. As early as 1883, he wrote in his Paradise
Found, the Cradle of the Human Race at the North Pole, a Study of the
Prehistoric World:
As to the primeval condition of our race, a
truly scientific mind will wish to base its conception not on the air-hung
speculations of mere theorists, but on an immovable foundation of fact, attested
and confirmed by the widest, oldest, and most incontestable of all concurrences
of divine and human testimony. According hereto, as in its beginning light was
light, and water water, and the Spirit spirit, so in his beginning Man was
Man. It says that the first men could not have been men without a
human consciousness, and that they could not have had a human consciousness
without rationality and freedom. It says that they could not have possessed
conscious rationality and freedom without the perception of ethical qualities
and the personal taste of moral experience. It boldly asserts that, according to
every principle of just analogy, the notion that it took the earliest men one
hundred thousand years to get an idea of the conditions of normal intellectual,
and ethical, and social living is as incredible as that it took the first-born
mammal one hundred thousand years to find it’s mother’s milk.[19]
But Warren’s clear affirmation that
primeval human life, while progressive in
everything which accumulating human experience would of necessity improve, was
almost god-like intelligences, as daring ultimately in evil as potent originally
for good was lost on the champions of the new humanism. His passionate defense
of the moral authority was also a voice out of tune with the currents of its
times: “It holds on the same authority that after centuries and possibly
millenniums of such history as great natures undisciplined by virtue are ever
reproducing, the social organism was incurably corrupted, and the moral
world-order itself defied. As Plato’s Egyptian priests told Solon, ‘the
divine portion in human nature faded out;’ the purely human ‘gained the
upper hand,’ and, spoiled by the very excellence of their fortune, ‘men
became unseemly...’[20]
One can cite more examples of this
nature from the nineteenth century but suffice it to say that the prevalent
trend of the 19th century was to look back at history with contempt.
This attitude was based on the unshakable belief in progress.[21]
Since everything was evolving, so was human knowledge and one day this progress
hoped to find out all that there was to be found, and the only sure vehicle to
this quest was science. This belief was furthered strengthened by the inventions
of ever-more sophisticated instruments and discoveries which created the
illusion of quantum jumps in human knowledge by generating a process which
churns out information at an alarming rate.
What was forgotten in this intoxication
with the idea of progress was a vertical axis which had pivoted human
consciousness in a primordial metaphysical realm that had made Man, as well as
everything else that existed in the cosmos, an integral part of an orderly whole
that rested on a metaphysical foundation which is the fundamental essence of all
ancient traditions.
The Descent of Man
For the sake of clarity, let us mention
in passing certain revisionists theories which try to rehabilitate Darwin’s
theism/teleology.[22]
These recent trends in rehabilitation of Darwin as someone who did not really
try to “throw God out the picture” have no solid basis and merely cloud the
debate. This is a strange but not unexpected trend in modern scholarship on
Darwin. These attempts at rehabilitation are not only against Darwin’s stated
position, they also go against the well-established historical realities of the
nineteenth century science to which we have briefly referred above. What is
missing in the Origin
of Species can easily be found in The
Descent of Man.[23]
In the introduction of this work, a
triumphant Darwin declared:
During many years I collected notes on the
origin or descent of man, without any intention of publishing on the subject,
but rather with the determination not to publish, as I thought that I should
thus only add the prejudices against my views. It seemed to me sufficient to
indicate, in the first edition of my ‘Origin
of Species,’ that by this work light would be
thrown ‘on
the origin of man and his history;’ and this implies that man must be included
with other organic beings in any general conclusion respecting his manner of
appearance on this earth. Now the case wears a wholly different aspect. When a
naturalist like Carl Vogt ventures to say in his address as President of the
National Institution of Geneva (1869), ‘personne,
en Europe au moins, n’ose plus suoutenir la creation indépendante et de
toutes pi èces, des esp èces,’ it is manifest that at least a large number
of naturalists must admit that species are the modified descendants of other
species; and this especially holds good with the younger and rising naturalists.
(p. 2) The first chapter, “Rudiments”, ends with the assertion: “Thus we
can understand how it has come to pass that man and all other vertebrate animals
have been constructed on the same general model, why they pass through the same
early stages of development, and why they retain certain rudiments in common.
Consequently we ought frankly to admit their community of descent; to take any
other view, is to admit that our own structure, and that of all the animals
around us, is a mere snare laid to entrap our judgment... It is only our natural
prejudice, and that arrogance which made our forefathers declare that they were
descended from demi-gods, which leads us to demur to this conclusion.” (P.
36-37) In any case, I use the term Darwinism to mean exactly what Darwin himself
meant: a dysteleological evolution based on random selection.
If there is any doubt left about
Darwin’s construction of Origin hypothesis, consider the following passage
from The Descent:[24]
The early progenitors of man must have been
once covered with hair, both sexes having beards; their ears were probably
pointed, and capable of movement; and their bodies were provided with a tail,
having the proper muscles. Their limbs and bodies were also acted on by many
muscles which now only occasionally reappear, but are normally present in the
Quardrunmana.[25]
At this or some earlier period, the great artery and nerve of the humerus ran
through a supracondyloid foramen.[26]
The intestine gave forth a much larger diverticulum or cæcum[27]
than that now existing. The foot was then prehensile,[28]
judging from the condition of the great toe in the foetus; and our progenitors,
no doubt, were arboreal[29]
in their habits, and frequented some warm, forest-clad land. The males had great
canine teeth, which served them as formidable weapons. At a much earlier period
the uterus was double; the excreta were voided through a cloaca;[30]
and the eye was protected by a third eyelid or nictitating membrane. At a still
earlier stage the progenitors of man must have been aquatic in their habits; for
morphology plainly tells us that our lungs consist of a modified swim-bladder,
which once served as a float. The clefts on the neck in the embryo of man show
where the branchiæ[31] once existed. In the lunar or weekly recurrent periods
of some of our functions we apparently still retain traces of our primordial
birthplace, a shore washed by the tides. At about this same early period the
true kidneys were replaced by the corpora wolffiana.[32]
The heart existed as a simple pulsating vessel; and the chorda dorsalis[33]
took the place of a vertebral column. These early ancestors of man, thus seen in
the dim recesses of time, must have been as simply, or even still more simply
organized than the lancelet or amphioxus.[34]
The case for Darwinism and neo-Darwinism
has always been helped by interpretation of scientific data and not on data per
se, for data does not speak. But even that data¾the
so-called “biological facts”¾which
were the bedrock of the “transformist illusion”, a telling term used by
Douglas Dewar as the title of his book,[35]
is eroding. Before I treat the question of evolution from cosmological
perspective, let me briefly mention some recent studies from a number of
scientific disciplines that have eroded the bedrock of Darwinism.
Let us also us recall what he wrote at
the beginning of the third chapter of The Descent of Man:
We have seen in the last two chapters that
man bears in his bodily structure clear traces of his descent from some lower
form; but it may be urged that, as man differs so greatly in his mental power
from all other animals, there must be some error in his conclusion. No doubt the
difference in this respect is enormous, even if we compare the mind of one of
the lowest savages, who has no words to express any number higher than four, and
who uses hardly any abstract terms for common objects or for the affections,
with that of the most highly organised ape. The difference would, no doubt,
still remain immense, even if one of the higher apes had been improved or
civilised as much as a dog has been in comparison with its present-form, the
wolf or jackal. The Fuegians rank amongst the lowest barbarians; but I was
continually struck with surprise how closely the three natives on board H.M.S.
Beagle, who had lived some years in England, and could talk a little English,
resembled us in disposition and in most of our mental faculties. If no organic
being excepting man had possessed any mental power, or if his powers had been of
a wholly different nature from those of the lower animals, then we should never
have been able to convince ourselves that our high faculties had been gradually
developed. But it can be shown that there is no fundamental difference of this
kind. We must also admit that there is a much wider interval in mental power
between an ape and man; yet this interval is filled up by numberless gradations.[36]
Darwin’s doctrine, presented in the Descent
of Man, was eagerly taken up by Ernst Haeckel in
Germany who had flair for graphic representations. He prepared a schematic
“history of man’s slow progress to the present” which shows how man
evolved from the lower forms [Fig.1]. Note that number 23 in the evolutionary
chain, is obviously human and
black.[37]

Figure
1
: Ernst Haeckel’s representation of the Descent of Man
Thus taken as a whole, the central tenet
of the Darwinian gospel claims that evolution is a gradual, undirected process
and it is the result of natural selection acting on small heritable differences.
In other words, living organisms evolve through continuous tiny changes and
without leaps, through a process that is opportunistic. Variations arise by
chance and are selected on the basis of the demands of the environment. In its
modern version, the evolutionism considers genes as the determinants of the
traits selected by the environment, defined as “heritable units of information
governing structures, development and function.”[38]
Neo-Darwinism: Scientific
Evolution of Evolutionism
During the last one hundred and fifty
years, Darwin’s ideas have gone through several changes and mutations. Since
the mid 1930’s, there has been a dramatic increase in literature that attempts
to prove these notions on the basis of biological sciences. The modern
synthesis, often referred to as “neo-Darwinism”, has tremendously changed
the original notions of Darwin’s theory and there now exist a vast amount of
data on mechanisms of evolution in various disciplines such as genetics,
microbiology and molecular biology, the central idea of Darwinism has not been
superseded by any new theoretical framework. This synthetic theory of evolution
has numerous fine tunings. For example, in one of its modern versions,
evolutionism considers genes as the determinants of the traits selected by the
environment, defined as heritable units of information governing structures,
development and function.
During the early twentieth century, many
young scientists who had been influenced by Darwin’s bold assertion produced
mountains of “scientific data” to support theory of evolution. During the
first two decades of the century, there were several variations of Darwin’s
theory. For example, Ernst Haeckel (1834-1919) claimed that “ontogeny
recapitulates phylogeny”, that is to say that there existed a parallel between
embryological development (ontogeny) and evolutionary history of the species
(phylogeny) such that the embryo passed through certain “lower” evolutionary
stages. Haeckel’s embryology arose from a combination of Darwinism and
Lamarckian notions of inheritance—the idea that traits acquired in an
organism’s lifetime could be inherited and become the basis for progressive
evolutionary change (Fig. 2).[39]

Figure
2
: Picture of Evolutionary Tree by Ernst Haeckel
August Weismann (1834-1914), on the
other hand defended natural selection and opposed any synthesis of Lamarckian
theses and Darwinism. Interested in microscopic studies, Weismann was convinced
that there is no force other than natural selection that controls evolution.
Thus at the dawn of the twentieth
century, scientific research followed certain clearly discernable lines:
biometry (statistical analysis of variations), cytology (studies of chromosomes
during cell division and fertilization), analysis of embryological development
and regeneration and the analysis of the inheritance by means of controlled
breeding experiments (Mendelism and mutation theory).
During the first three years of the
century, Hugo de Vries (1848-1935) came up with The Mutation Theory,
which sought to revise Darwin’s ideas. de Vries argued that slow, cumulative
selection of minute variations was not the way of evolution of new species;
rather novelty in population was the result of discrete discontinuous changes,
which he called “mutations”. He tried to show how his theory could account
for the appearance of a “genuinely new” species in one step. Basing his
theory on his knowledge of agricultural breeding practices and controlled
experiments designed to trace the appearance of mutations, de Vries argued that
natural selection, acting on these small populations or “elementary species”
merely determines which ones would survive.[40]
Hugo de Vries was influential in
creating enthusiasm among American biologists who studied a large variety of
plants and claimed discoveries of mutations at an astonishing rate. The interest
in the theory of discontinuous variations and the possibility of controlling
that discrete and abrupt change which produces new species was influential in
reviving interest in Mendelism.[41]
In 1906, William Bateson of the
University of Cambridge launched the term “genetic” at a scientific
conference and revived interest in Mendel’s work. But within three years
—the centenary of Darwin’s birth—Bateson was under attack by the
supporters of Darwin. The notions of continuity of species were re-emphasized
and Batesonians and Mendelians were accused of exaggerating the prevalence of
discontinuous variability in nature.
The publication of Genetics
and the Origin of Species by the Russian
naturalist Theodosius Dobzhnaksy (1937)[42]
who came to New York in 1927 and remained in the United States for the rest of
his life, established the field of genetics on experimental footings. Dobzhansky,
a trained entomologist, cooperated with experimental geneticist Alfred H.
Sturtevant in the 1930s and focused on wild populations of fruit flies for the
study of evolution in nature. Dobzhansky argued that microevolution (genetic
processes that produce small evolutionary changes) and macroevolution (broader
patterns of evolution observable in the fossil record) were part of a single
continuum and thus all evolutionary patterns could be explained by the ordering
of small genetic changes by natural selection.
Dobzhansky’s work was further
supported by others who focused on causal mechanisms¾the
how and why of evolution¾rather
than on simple description of the evolutionary record. Thus “C.D.
Darlington’s The
Evolution of Genetic Systems (1939), Ernst
Mayr’s Systematics
and the Origin of Species (1942), George Gaylord
Simposon’s Tempo
and Mode in Evolution (1944) and G. Ledyard
Stebbins’ Variation
and Evolution in Plants (1950) refocused attention
on the detailed study of evolution as a process, with an emphasis on how natural
selection operated and what its effects were.”[43]
In the 1940s, the “hopeful monster”
theory of geneticist Richard Goldschmidt became famous. It basically proposed
that occasionally large, coordinated changes might occur just by chance. In
1958, when J. C. Kendrew determined the structure of myoglobin using X-ray
crystallography, it came to light that proteins were not a simple and regular
structure like salt crystals; they were extremely complex. With the advancement
of Nuclear Magnetic Resonance (NMR), it became even easier to determine the
structure of complex proteins but one thing these instruments could not do: they
could not produce evidence for even a single new species formed by the
accumulation of mutations.
With the development of more
sophisticated instruments, computers, and through investment of millions of
dollars of research funding, evolutionism became the mantra of post World War
western science. The postwar decades also saw the reemergence of interest in the
mathematical approaches. Population geneticists and population ecologists joined
hands with biologists and mathematicians to produce an enormous body of
literature in which flew all kinds of theoretical constructions, theological and
philosophical baggages along with such theories as game and information
theories. Von Frisch, Konrad Lorenz and Niko Tinbergen, the winners of 1973
Nobel Prize for their work in ethology focused on the experimental analysis of
behaviour. Von Firsch published his renowned work on the “dance language” of
bees, revealing the complexity of behaviour of “lower organism” and
Lorenz’s pioneering work on birds demonstrated how experiments could cast
light on instinctive behaviour. This renewed interest in ethology stimulated
research in the field of behavioral ecology and in the study of genetics in
relation to behaviour, opening up new areas of research in evolutionary biology.
But before fading into history, these
debates produced another controversy. In 1975, a Harvard biologist, Edward O.
Wilson, published Sociobiology:
The New Synthesis. The book claimed to open a new
field of sociobiology at a time when Francis Crick and James Watson were riding
the wave of popularity following their discovery of the double-helical structure
of DNA. Wilson’s emphasizes on the biological basis of behaviour over cultural
and historical causes and his extrapolation of results from zoology to humans
were considered to be highly speculative. Social behaviour was seen as adaptive
traits molded by natural selection and genetic reductionism was considered a
valid methodology. Richard Dawkins’ best selling book The
Selfish Gene (1976) created further uproar on the
question of genetic determinism.
There were surely voices against these
trends. Those who found the methodology of sociobiology speculative and unsound
were, however, not always successful and the evolutionary and genetic study of
behaviour arched over to such fields as anthropology and psychology; it also
revived interest in primatology. The use of primates for research into the
questions of origins was nothing new but new primatology became a tool for
feminine approaches to science and other studies which focused on sexual
selection.
The early 1970s also saw the rise of the
theory of “punctuated equilibrium”. First proposed by the American
paleontologist Niles Eldredge and then developed and aggressively promoted
by Stephen Jay Gould. This non-gradualistic model, proposed by Stephen J.
Gould and Niles Eldredge, postulates that for long periods most species undergo
little observable change, then a rapid change occurs in small, isolated
populations and this explains why no fossil intermediates have been found.[44]
Punctuationists emphasized speciation over phyletic evolution. This model
contradicted views of gradual, linear, slow evolutionary change. The model
itself was not totally new. Mayr, for example, had proposed years ago that
evolution might proceed rapidly in small, isolated populations. Punctuational
model emphasized the abruptness with which the new forms appeared, including the
sudden appearance of humans. It suggested an episodic sequence of events and not
the gradual directional change. It gathered strength from the discoveries in the
1960s and 1970s in Africa, which cast doubts on the earlier assumptions of a
graded morphological series. Dating of the African fossils had pushed the age of
hominides back to between three and four million years; thus raising new
controversies about the relations of the fossil forms to each other and to
modern humans.
However, all of these mutations of the
original theory need the same blind force that produced the original: chance and
necessity; they merely differ in detail. The so-called Cambrian explosion, which
rests on the findings that only a small number of fossils of multicellular
creatures are found in rocks older than about 600 million years whereas rocks of
slightly younger age have a profusion of fossilized animals, demanded that a new
explanation has to be advanced. The estimated time over which this explosion is
thought to have occurred is 10 million years. This prompted Stephen Jay Gould to
argue for mechanisms other than natural selection. Once hailed as biological Big
Bang, the Cambrian explosion has, however, also passed into history as further
evidence was piled up for more detailed theories.
These theories come by the dozens. For
each theory, there exists another refuting it. A case in point is the famous
exchange between Francis Hitching, the author of The Neck of the Giraffe,[45]
and Richard Dawkins, the author of The Blind Watchmaker.[46]
Hitching had described the remarkable defensive system of the bombardier beetle
as proof against blind chance. This somewhat inaccurately described passage from
The Neck of the
Giraffe states:
Brachinus,
commonly known as the Bombardier Beetle, squirts a lethal mixture of
hydroquinone and hydrogen peroxide into the face of its enemy. These two
chemicals, when mixed together, literally explode. So in order to store them
inside its body, the Bombardier Beetle has evolved a chemical inhibitor to make
them harmless. At the moment the beetle squirts the liquid out of its tail, an
anti-inhibitor is added to make the mixture explosive once again. The chain of
events that could have led to the evolution of such a complex, coordinated and
subtle process is beyond biological explanation on a simple step-by-step basis.
The slightest alternation in the chemical balance would result immediately in a
race of exploded beetles (p. 68).
Dawkins, in turn, proceeds to show the
basic flaw of this statement by mixing the two chemicals in question. After
describing the case from Hitching, Dawkins writes with relish:
A biochemist colleague has kindly provided
me with a bottle of hydrogen peroxide, and enough hydroquinone for 50 bombardier
beetles. I am now about to mix the two together. According to the above, they
will explode in my face. Here goes... well, I’m still here. I poured the
hydrogen peroxide into the hydroquinone, and absolutely nothing happened. It
didn’t even get warm... (p. 87).
Dawkins then goes on to explain that
though the bombardier beetle does squirts a scalding hot mixture of hydrogen
peroxide and hydroquinone at enemies, these two chemicals do not react until a
catalyst is added. And he makes the point that these chemicals were present in
the body for other reasons and the ancestors of the bombardier beetle just
evolved the mechanism of using these chemicals for defence—chemicals which
“happened to be around”. And he finishes his case by making the statement:
“That’s often how evolution works.” (p. 87)
With the discovery of the
deoxyribonucleic acid (DNA), the battleground was shifted to even smaller
scales. Evolutionary processes had to be placed in the DNA of a reproductive
cell. Here too, we have a plethora of theories, each claiming to solve the
ultimate problem of Origins. But each, with its antithetic. Thus from DNA, the
hope of neo-Darwinists shifted to RNA (ribonucleic acid), a single-strand
molecule which was thought to be an integral collaborator of DNA in protein
synthesis.
Through these successive failures, what
has become obvious is the fact that there exists an irreducible complexity at
the beginning and this irreducible complexity could not have arisen out of
chance.
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