February 12th
2009 saw the 200th anniversary Charles Darwin’s birth.. The
beautifully simple idea embodied in his most famous book, Origin of the Species – evolution
by natural selection – was a revolutionary departure with profound scientific
and philosophical implications.&Following the
footsteps of Copernicus and Galileo three hundred years earlier, Darwin battered an
enormous, irreparable breech in the walls of Fortress Theology and for that
reason the book has been the source of intense debate right up to the present
day. Darwin
sought and found an explanation – a mechanism – for the evolutionary changes in
species, which other scientists were beginning to suspect, using a purely materialist method, without any recourse
to God or metaphysics.
Because of its
challenge to religious orthodoxy, Darwinian evolution is still dismissed today
by millions of people who would otherwise scoff at outdated scientific ideas
like a flat earth:
“Gallop Polls conducted in the United States between 1982 and
2004, consistently found that between 44 and 47 per cent of Americans do not
believe in evolution. Instead, they believe that humans were ‘created by God
pretty much in their present form less than 10,000 years ago.’
Meanwhile, a recent survey of more than 400
university professors in Texas,
a largely conservative state, found that nearly 90 percent believe modern
evolutionary biology is largely correct.”[1]
More alarming
still was the survey conducted in Britain among science teachers last year, indicating that a sizeable minority (29
per cent) thought that creationism should be taught as a valid alternative to
evolution! As Steve Jones, professor of genetics at University College London,
put it, “Do these teachers believe that they should also teach the possibility
that water is H3O, that Bacon wrote Shakespeare and that babies are
brought by storks?”
In September
last year, a day after the Church of English apologised for not having
‘understood’ the ideas of Charles Darwin 150 years ago, the Catholic Church
announced that it too was going to hold a five-day conference on the
significance of Darwinism. There were, of course, howls of protest from
anti-evolutionists who still interpret the Genesis book of the Bible as an
exact and literal description of the history of the planet.
The Origin of
Species
Darwin’s starting point in Origin was
the observation that within the population of a species there is a natural variation among its individual organisms. For example, birds of the
same species are recognisable by the general feature that they have in common
and which define the species, but each individual may have slightly different
wing colour, beak length, weight and so on.
The same, of
course, applies to humans: we are not identical copies or clones of our parents
and with the exception of identical twins, all of us have genetic
characteristics that are unique to us, even compared to parents and close
siblings. We all share the general (species) characteristics of homo sapiens and we may resemble our parents, but in regard to
the fine details, we are all unique.
Darwin went on to note that apart from the general characteristics that go to make up the particular species, each
individual would tend to pass on its own
unique characteristics to the
next generation. If, for example, two male pigeons with different wing length
were to mate with similar females, the nestlings of the shorter-winged male
would also tend to have shorter wings and the nestlings of the longer-winged male
would tend to have longer wings.
As Darwin explained, humans
have used the properties of natural variation and inheritance for generation.
By artificially selecting which
domestic animals would be allowed to breed, it has been possible to change –
gradually, and generation by generation – the features of any given domestic
animal population. Dogs, cats, cows, horses, pigeons, not to mention plants,
have been “bred” to have certain useful features for millennia, precisely by selection of which organisms would be
allowed to procreate.
In contrast to
this artificial selection, Darwin posed the issue of
natural selection. Whereas a farmer
may decide which of his horses is allowed to breed, in the wild it is “nature”
which determines which organism is more likely to reproduce, moreover, as a
process effective over a far, far longer period of time. Darwin suggested that there was competition between organisms of the
same species to see which one would be the most successful at breeding. In what
Darwin called “the struggle for life”, those organisms which had
characteristics best suited to the environment in which they lived would be the
most successful at reproduction, by surviving long enough to reproduce more
often or more successfully.
“Owing to this struggle for life, any variation, however slight and
from whatever cause proceeding, if it be in any degree profitable to an
individual of any species, in its infinitely complex relations to other organic
beings and to external nature, will tend to the preservation of that
individual, and will generally be inherited by its offspring. The offspring,
also, will thus have a better chance of surviving.”[2]
Many
characteristics may simultaneously be under environmental “pressure” to change
– leg length, binocular vision, fur colour, digestive processes,
disease-resistance, mating strategies, tail length, teeth size, shape and configuration, etc, etc. Thus a whole animal (or plant) evolves, in all
its complex characteristics and features.
The idea of
evolution by natural selection became ‘survival of the fittest’ under the
influence of Wallace, a collaborator, but was never a phrase embraced with any
enthusiasm by Darwin himself. Wallace’s phrase is suggestive of a population in
constant conflict within itself, struggling selfishly so that only the
strongest and fittest survive on merit. The formulation has been used ever
since Darwin to ‘justify’ racism and class society, with the implication that
those who find themselves at the bottom of the social pile are somehow less
‘fit’ and therefore less deserving than the powerful and wealthy at the top of
society.
Darwin’s Origin of Species used
the expression natural selection, which is a simpler and more accurate
description of the process in question. Having uncovered the mechanism of
evolutionary change in the material
conditions of living things, Darwin
was able to explain “speciation”, the formation of new species. He suggested
that different parts of a species population may become physically isolated
from one another – by mountain ranges or on different islands, for example – so
that they experience different environmental pressures.
The science of
geology was not well developed in Darwin’s time, but we are well aware now of
the movement of continents and the uplift of mountains to see how populations
of plants and animals could potentially be split and subsequently isolated from
each other. Darwin himself used the example of the different islands in the
Galapagos to show how even on this relatively modest scale differences in
environment produced different species of finches and tortoises.
Over time the
different environmental pressures drive the evolution of the two populations in
different directions so that they become physically distinct from each other.
Eventually, as a Marxist would say (although, of course Darwin did not) quantity is transformed into quality and
the differences become so great that two organisms from different parts of the
population, should they come back into contact, would be unable to successfully
interbreed – two separate species would
then exist.
There are
examples today of species that have clearly moved apart through evolution but are
still close enough to breed – like tigers and lions or horses and donkeys. But they
are already far enough apart for them to be unable to breed successfully – their offspring, ligers
and mules, are sterile. In one fell
swoop Darwin
was able to explain, in terms of natural laws, how modern species had developed from earlier species and why there was such an enormous variety
of species – we now know running into millions – on the planet.
It is surprising
that Darwin’s
ideas are often misunderstood, even by other scientists (although not often
those in the field of biology). The astronomer Fred Hoyle once famously remarked
that accepting evolution was like believing that a “hurricane could blow
through a junk-yard and accidentally assemble a jumbo jet”. But what Fred Hoyle
failed to appreciate was that it is the successive
accumulation of ‘useful’, small, incremental changes that leads to the
formation of new species, not a single one-in-a-billion genetic mutation.
The most
significant point about Darwin’s
simple idea was that the rise of species was based on the material conditions faced by organisms and that the evolutionary
process was without aim or purpose. The
most complex organic structures, like eyes, brains and other internal organs,
not to mention the complex social structures we see in ants and bees, have all come
into being as a result of the blind laws
of natural science. Nature, as Richard Dawkins puts it, is a “blind
watchmaker.”
What was also
important is that natural selection knocked human beings off their theological
pedestal. Even where evolution was grudgingly accepted, it was assumed that it must
reflect some purposeful progression
to a ‘higher’ and ‘higher’ level, towards the ideal of Mankind. This idea, too,
was brought to down to earth.
Darwinism, in
short, was a huge blow to the Church and those scientists who held metaphysical
notions of an evolution guided by the hand of God. Darwin’s theory was enormously powerful in
its beautiful simplicity and its undeniable foundation in solid facts and evidence.
Discoveries of the fossil remains of extinct organisms,
alongside other evidence showing the great age of the earth – for example in
the work of Charles Lyell – was already challenging any literal interpretation
of the Genesis story of creation. But it would be a
mistake to underestimate the challenge these ideas faced and the extent to
which religion underpinned so much alleged ‘science’ in Darwin’s time.
The Church
fought back in hundreds of works by scores of professors – mostly in works
understandably forgotten today. Between 1833 and 1840, for example, a series of
eight books were published “On the Power, Wisdom, and
Goodness of God, as manifested in the Creation”, each written by a leading
authority in moral philosophy, natural history, astronomy, physiology,
chemistry, and geology. The books were widely discussed, and extracts often
appeared in sermons.
One of these, on
geology, was written by William Buckland, professor
of geology at Oxford.
Its chapter headings included: “Proofs of design in the structure of fossil
vertebrates”, “Proofs of design in the structure of fossil vegetables”, “Proofs
of design in the effect of disturbing forces on the strata of the earth”, and
so on.
In one chapter, he
discusses the fossil remains – some of which had been provided by Darwin from his Beagle
voyage to Chile
– of a Megatherium, an animal much like a giant sloth. On the
basis of a reconstruction of its shape and physiognomy, Buckland concluded, Megatherium was no “monstrosity” as some
anatomists had argued, but “evidence of God’s wisdom and benevolence as a
designer”.
In the 1840s, another comparative anatomist, Richard Owen,
argued in a series of publications that the animal kingdom was arranged
according to four distinct organisational plans or types (fish, birds,
reptiles, and mammals). These ‘archetypes’, as he called them, were originally
conceived in the mind of the Creator.
Another book, written by the geologist and Calvinist Hugh
Miller, Footprints of the creator (1847), argued that evidence could
be found in fossil formations of the biblical flood. And so on, this being a
tiny sample of the theological ‘science’ of the day.
Darwin’s own ideas of religion
In his lifetime,
Darwin couldn’t
completely break away from the Christian tradition in which he had been born
and raised. Most of his friends, family and associates were part of the
established Anglican Church and he supported the Church as a social
institution. The Church, in any case, pervaded all aspects of academic life and
association with it was often a condition of acceptance into teaching and
research posts. Many of Darwin’s
own former teachers were linked in this way to the Church of England.
Darwin developed the main outline of his ideas many years before he came
to publish them – as long as twenty years earlier – and one of the reasons for
that was his difficulty in reconciling his ideas with established religion and
philosophy. When he did come to publish Origin
he left aside the question of human evolution in one enigmatic phrase: “light
will be thrown on the origin of Man and his history.” However, the implications
were clear and twelve years later he published The Descent of Man, bringing natural selection into human
development.
Nevertheless,
his theories inevitably meant that his supporters frequently found themselves
debating evolution with Church leaders and it is now clear from his papers that
his scientific studies did have an influence on his private thoughts.
In his
autobiography he wrote:
“The
old argument from design in nature…which formerly seemed to me so conclusive,
fails, now that the law of natural selection has been discovered. There seems
to be no more design in the variability of organic beings and in the action of
natural selection, than in the course which the wind blows.”
On the existence
of a ‘Creator’ he wrote to Charles Lyell in September 1874:
“Many persons seem to make themselves
quite easy about immortality and the existence of a personal God by intuition;
and I suppose that I must differ from such persons, for I do not feel any
innate conviction on any such points.” [3]
Again, in a letter to F A McDermott, in November 1880, he
wrote:
“I am sorry to have to inform you that I do not
believe in the Bible as a divine revelation, and therefore not in Jesus Christ
as the son of God.”
Marx and Engels on Darwin
For the founders
of dialectical materialism, the ideas of Darwin
represented a brilliant confirmation of their world view. Darwin did not speak in the language of
dialectical change, but his ideas certainly groped in that direction. But more
importantly, the entire basis of Darwinism was rooted in a materialist viewpoint. In
January 1861, Marx wrote to Engels:
“Darwin’s
book is very important and serves me as a natural scientific basis for the
class struggle in history. One has to put up with the crude English method of
development, of course. Despite all deficiencies, not only is the death-blow
dealt here for the first time to ‘teleology’ [the explanation of phenomena by
their purpose – JP] in the natural
sciences but its rational meaning is empirically explained.”
Writing in Anti-Dűhring, Engels anticipated the
further development of Darwin’s
ideas:
“The theory of evolution is however still in a very early stage, and
it therefore cannot be doubted that further research will modify our present
conceptions, including strictly Darwinian ones, of the process of the evolution
of species.”
Indeed, over the
last 150 years since the publication of Origin,
Darwin’s
ideas have not been refuted by science, but have been clarified, refined,
quantified, deepened and developed by a vast accumulation of experimental
evidence.
Darwin drew upon the geological work of Lyell which emphasised the almost
unimaginably (for the day) old age of the Earth, against the opposition of the
Church, which was created according to one learned bishop in 4004BC on a
Tuesday afternoon. Darwin’s
Origin, following the same pattern as
Lyell, placed the greatest emphasis on the gradual
evolution of species over thousands of generations, putting the biological
processes on the same time-scales as the geological. The emphasis was on slow, gradual change.
Even today, many
Darwinists are gradualists, seeing
evolution as a more or less slow and continuous development. Other ‘Neo-Darwinists’
have refined the idea of speciation to embrace the possibility of rapid changes (rapid in geological
terms, ie thousands rather than millions of years), interspersed with gradual change.
The so-called “punctuated
equilibrium” model of Stephen Jay Gould and Niles Edredge is based on this idea
of mass extinctions and mass speciation at key moments in
biological history:
“…change does not usually occur by imperceptibly gradual alteration
of entire species but rather by isolation of small populations and their geologically instantaneous transformation
into new species.” [4](emphasis
added)
There is indeed,
ample evidence, for example, for an “explosion” in speciation at the beginning
of the Cambrian era, 700 million years ago. Although the authors of this model
don’t use the expression, in fact it comes close to the idea of dialectical change described by Marx and Engels.
Many scientists
now accept that there may be periods of relative equilibrium biologically,
interspersed with rapid, sometimes catastrophic
change. Some changes are ‘gradual’ – like continental drift that moved
enormous land masses across the surface of the earth. (Although tectonic plate
movements are achieved by a long series of minor shocks and earthquakes, all of
which, on a local scale, may be ‘catastrophic’ to the environment.) Other
changes, on a geological time-frame, may be sudden and dramatic. There is now
some evidence that catastrophic volcanic activity or asteroid impact may have
had dramatic impacts on biological processes on Earth.
The important
point is that none of these ideas refute Darwinism, they merely add to it and
develop it.
Mechanisms of evolution uncovered in molecular
chemistry.
Darwin developed his theory from the careful observation and measurement
of thousands of animal and plant species. He examined the principally the
anatomy and to a degree the physiology of
these living organisms. He himself wrote that “the laws governing inheritance
are quite unknown…”[5] –
he had no understanding of the physical mechanism underlying inheritance and
evolution.
In the century
and a half since he wrote these words, scientists have come to understand the
underlying chemical mechanism of
inheritance, through complex molecules like DNA and RNA. There is an entire body of knowledge that
links the genetic make-up of all living organisms – the so-called genotype – to its physical expression as
a living organism – the phenotype.
Giant molecules
like DNA and RNA are now known to be the templates for protein synthesis in all
living organisms and they have the capacity to carry ‘genetic code’ by varying
combinations of the four bases along the length of the molecular chain.
What
dramatically underlines the Darwinian theory of evolution is that it is now
clear that the fundamental genetic make-up of all living things on the planet –
without exception – rely on the same basic biochemical mechanisms. In other
words, the development of all modern
molecular science has reinforced the fundamental ideas of natural selection put
forward by Darwin
150 years ago.
The modern opponents
of Darwinism – chiefly religious fundamentalists inspired by the book of
Genesis – are not just rejecting evolution but are in fact rejecting all of modern biochemistry, which is itself
drawn from the research and discoveries of millions of scientists, all over the
globe, for the last 150 years. In fact, creationists – including the supporters
of so-called Intelligent Design – if they were consistent, would have to reject
all of modern science.
Darwinism has
become one of the most important ‘isms’ of our age. Despite the influence of
religious fundamentalism, it is an idea accepted by the large majority of
scientists today. It is an embedded part of our culture. A Google search on the internet gives 2.8 hits for Origin of the Species, 2.3 m hits for Darwinism and 15.2 million for natural
selection!
Like the ideas
of that other ‘ism’ – socialism – it is rooted in material reality and it will
therefore not go away. As the American philosopher Daniel Dennett has put it,
“(Darwinism)…is securely tied by hundreds of thousands of threads of evidence
anchoring it to virtually every other areas of human knowledge.”[6]
Darwin’s theory
remains today the ‘grand unifying theory’ of biology.
It is entirely
appropriate for Marxists to celebrate the work of Charles Darwin, in his impact
possibly the most influential natural scientist of all time. Although his ideas
were in this or that respect not fully rounded or developed they placed the
entire science of biology on a solid materialist foundation for the first time
and placed the biology of human development firmly within it.