This entry will deal with the thought of Charles Darwin. From the Voyage of the Beagle and The Principle of Divergence to Natural Selection and the Descent of Man, Darwin displays remarkable changes (and consistencies) in the nature of his reasoning. As his ideas emerge into society at large they evolve in remarkably conflicting and often disturbing ways. This essay is a first step towards a better understanding the phenomenon and complex legacy of Darwinian thought.
When Charles Darwin set off on his voyage aboard the Beagle there was absolutely no sign that this relatively simple naturalist would cause such a great wave in western thought. His student years were the epitome of mediocrity––hunting and gambling his days away––and his presence on the ship seems to have been not much more than an after thought. The ship’s captain, a phrenologist, almost denied Darwin passage on the ship because the shape of his nose seemed to indicate undesirable moral tendencies (laziness). But Darwin seemed to have an innate passion for natural history and, through his friend Adam Sedgwick, found himself very interested in geology. The works of Alexander Humbolt and John Herschel were also very influential to Darwin––while Humbolt’s scientific travelogues sparked in Darwin the urge to travel, Herschel’s investigations into natural philosophy introduced him to rigourous philosophical and scientific thought. It was, however, geology that would first inspire Darwin’s theoretical task.
Lyell’s Principles of Geology influenced Darwin profoundly. Lyell presented a rigourously empirical historical view of natural science oriented around five key ideas:
1. The geologist investigates both the animate and inanimate changes that have taken place during the earth’s history.
2. His principal tasks are to develop an accurate and comprehensive record of those changes, to encapsulate that knowledge in general laws, and to search for their causes.
3. This search must be limited to causes that can be studied empirically.
4. The records or ‘monuments’ of the earth’s past indicate a constant process of the ‘introduction’ and ‘extinction’ of species, and it is the geologist’s task to search for the causes of these introductions and extinct ions.
5. According to Lyell, the only attempt to deal with 4 above, that of Jean Baptist Lamark who proposed the idea that species are capable of ‘indefinite modification’, is a failure on methodological grounds; for Lyell all the evidence supports the view that species variability is limited, and that one species cannot be transformed into another.
Well before Darwin arrived in South America, a fiery debate was raging with regards to the geological nature of the earth and the origins of life itself. The Platonic forms and the Aristotelian ‘chain of being’ were being challenged; and the biblical concept of creationism was being modified in an attempt to accommodate compelling new modes of thinking about the nature of life which had been introduced largely because of correlative observations made in the fossil record and geological strata. Although the idea of evolution had been introduced long before, these new observations challenged the Christian values which lay at the centre of 19th century British society in an unprecedented way. The Church countered these challenges as best it could. Arguments were made by faithful scientists with regards to the age of the planet, who claimed that it was too young to allow for evolution, and for the permanence of the geological structure of the earth––the only changes incurred were those brought on by God’s great flood. Change of any type, whether it be evolution, the introduction of new species or the extinction of others, geological or living, was inconceivable. But this was at odds with clear empirical evidence in the fossil record that demonstrated that some animal types disappear while others seem to undergo drastic changes. Christian scientists tried to explain this by putting forth the theory that there had not been one cataclysmic flood but many––God deliberately destroying his creation and recreating it. It soon became clear, however, that what was being observed was a process of transformation: invertebrates in the oldest and lowest level of the fossil records, then fish, reptiles, birds, mammals and man at the highest and most recent level. For a while pious scientists were able to counter this with the claim that these developments were distinct instances of creation and that the idea that new animal and plant types were evolving was merely an illusion.
While other defences were put up with varying degrees of success by the Christian scientific establishment, Natural Theology being chief among them, the growing feeling was that these transformations observed in the fossil record were the result of a gradual process rather than individual instances of creation. As the study of geology improved, the gaps between records became smaller thus reinforcing the idea of a continuous process; the observation of common rudimentary organs, sometimes non functional in certain species, brought Intelligent design into question; the common structure of vertebrate limbs as well as the observed similarities in embryonic development across animal types suggested common ancestry; evidence of the successes in selective animal and plant breeding as well as the discovery of new ‘non-biblical’ species in Australia questioned the permanence of types. All of this evidence, as well as the understanding that animals generally reproduced faster than the available food supply––resulting in a ‘struggle for existence’––led many to begin to view the world as a unity which was slowly changing its appearance under the influence of forces which were acting in the present moment.
Reflecting on his observations in South America and the Galapagos islands, Darwin was indeed confronted with certain facts that did not agree with the accepted Christian model of life and creation. Darwin became convinced that the fossil record and the current distribution of species could only be due to the gradual transformation of one species into another and was determined to articulate a theory to explain this that measured up to Lyell’s principles. He set out describe the process that produced the systematic patterns in the fossil record and the otherwise strange biogeographic distribution of species. He realised that he would eventually need to come up with a causal theory that would account for the transformations implied by his observations; every element of the theory would have to identify ‘causes now in operation’, which could be investigated empirically. For Darwin, the problem, and the methodological constraints, had been outlined by Lyell and defended philosophically by Herschel; but there were, however, other theories put forward by some of Darwin’s contemporaries and predecessors which would also profoundly influence the way he viewed things.
For Lamark, all living creatures––all ‘organic matter’––contained, in a manner of speaking, a will to self improvement. Lamark claimed that the behaviour and needs of the animal would lead to the development of certain traits; as a species inevitably moved its way upwards to greater complexity, matter formed itself into basic creatures which filled in the space opened up by this ascent. This endless process of generation put forward by Lamark––a development on the Aristotelian chain of being––was scorned by Darwin’s hero Lyell, and publicly given very little credence by Darwin himself, although it certainly had an effect on his thought. The Lamarkian position most certainly influenced Darwin’s ‘Theory of Pangenesis’ which we will discuss later. In addition to the concept of the ‘struggle for existence’ proposed by Erasmus Darwin and Buffon, the work of Chambers, which posited that the progression of fossil types was the evidence of the unceasing transformation of God’s initial creation created such a scandalous uproar that it could not have gone unknown to Darwin.
Darwin’s observations across the South American pampas eventually lead him to view the process of transformation as ‘continuous descent with modification.’ He saw a connection between the historical resemblance of organisms and their geographical proximity: different types of ostriches or armadillos seemed to descend from similar ancestors––they did not appear to be representative of separate instances of creation but rather the results of geographic separation. Bifurcating from a common ancestor the ancestors of the different types of ostrich would eventually become so estranged from each other that interbreeding would become impossible. Darwin’s experience on the Galapagos islands confirmed what he had observed on the continent. Despite the fact that the environmental conditions were very similar from island to island, the populations of birds and lizards that populated them bore unmistakable differences. Darwin would come to the conclusion that the separation of these animals had permitted the populations to vary independently from island to island. Ultimately this view would now put Darwin in conflict with Lyell who contended that, while the earth itself undergoes extensive changes, living organisms remain constant. For Darwin, Lyell’s objection to biological change was made incoherent by his belief in geological change.
Like Lamarck, Darwin initially saw biological evolution as being influenced by environmental change, as an adaptive process; but he also realised that, contrary to Lamark, the process could not be seen as a continual line of ascent. His observations had shown him that a given organism could evolve into a more complex organism with out disappearing itself. This developed into a concept of ‘adaptive radiation’ which posited the evolutionary movement of organisms into all possible habitats. Thus Darwin presents his theory of a tree of life in which all life branches out irregularly from a common stem.
But Darwin’s theory was not original. It owed profound debts to Lamark as well as Erasmus Darwin; the theory of common ancestry had also been postulated by Diderot and in the field of linguistics by Jones and Bopp. And, although Darwin had come some way in explaining how evolution works, he still had no idea why it worked––what was driving this process?
As we saw above, Darwin started by taking the position that evolution was prompted by environmental changes which bring about changes in behaviour––he was never able to quite shake off the spectre of Lamark. Darwin then moved to an hypothesis which stipulated that sexual reproduction produced ‘random unsolicited novelties’; and that positive ‘novelties’, or variations, would have the tendency to propagate themselves. While Darwin was very interested in the ways in which plants and animals had been selectively (consciously) bred by humans, he could not bring himself to believe that natural evolution worked in this way. Although Darwin was aware of the idea of the struggle for existence put forward by his grandfather and Buffon, it was only after examining the mathematical model of population growth put forward by Malthus that he came to the conclusion that any organism which found itself in the possession of a favorable variation would be more likely to survive and reproduce––whether it be the ability to move into new habitat (divergence), more easily aquire food and mates, or evade predators. For Darwin the only solution was a theory of blind competition which eliminates the unfit: Natural Selection.
Darwin still had problems. While he now had a theory, it was not one that lived up to the principles of credibility as he understood them. Darwin had always hoped to develop a properly inductive theory, but all he had was an hypothesis. He began to accept the fact that evolution would not be able to be observed directly and that the only way to present his theory in an acceptable manner would be to amass such an overwhelming volume of indirect evidence that deduction of his ideas would be impossible to escape. And, he still had not effectively explained the means by which variation was caused and maintained.
In attempting to explain causes, Darwin was caught between chance variation or the development of ‘random unsolicited novelties’ on one hand, and the idea that environment (Erasmus Darwin, Buffon) and the generational effects of use and disuse (Lamark) played a decisive role on the other. Indeed, the very title he gave to his theory, Natural Selection, is ambiguous in this regard and his texts vacillate between these concepts. At this point Darwin seems to give up on his cherished notions of scientific rigour, postulating theories which had little or no compelling evidence to found them. His theory of ‘Pangenesis’ suggested that physical traits acquired by parents during their life time such as muscle growth or certain talents were inherited by the offspring––this could also work in reverse. As Weismann later showed, the kind of clear rigorous research into observable facts that Darwin so excelled at in his earlier yeas would have been sufficient to prove that no compelling evidence exists for such a theory and that offspring invariably revert to type. Perhaps because of the lack of a genetic model on which to base an understanding of the connection between generations, this profoundly Lamarkian theory found a large audience in the United States where the clear causal––but unscientifically founded––model of the inherited effects of use and disuse and environmental influence were preferable to the chance effects of ‘unsolicited variation.’ Indeed, even with the advancement of modern genetics, many continue out of ingnorance, or preference, to understand evolution in this way.
Darwin’s own vacillations with regards to the interpretation of his observations allowed his audience to interpret the theory itself in a number of ways. And indeed, many began to pose the question: does natural selection work at levels other than the level of Darwin’s focus? Darwin himself offered a social theory in the Descent of Man. While the phrase “favoured races” which appears at the beginning of Origin of Species certainly refers only to pigeons, it does seem to echo throughout Darwin’s ‘Descent’ under the guise of the evolution of races as a driving force of human advancement. This unrepentantly classist and anglo-centric document––the spectre of Malthus looming heavily all the while––contributed greatly to the development of racialism which promulgated wildly speculative ideas regarding the superiority of races while masquerading as science. Again, Darwin vacillates in his understanding of man’s place in natural selection and society, leaving himself open for interpretation. This led to unfortunate consequences such as Social Darwinism and the development of other racist and economically exploitative doctrines that gave themselves credence by associating themselves with the increasingly deified Darwin.
As the figure head for contemporary naturalists and environmentalists, and as the foundation––at least in part––for the “scientific” credibility of laissez-faire economics and colonial military expansion, the iconic name ‘Darwin’ has taken on many guises over the course of the last century. The triumph of Darwin the man was to create the most comprehensive empirical model of the distribution and evolution of species; and indeed, modern genetics still uses his model a fundamental part of the interpretation of its data. But, while Darwin’s thought has inspired an appreciation of the mystery and beauty of nature and has undoubtedly played a crucial role in our understanding of biology and genetics, it has also contributed, directly or indirectly, to the creation of the social nihlism and malaise that are so characteristic of the 20th century––this due, perhaps in part, to the conclusion many have drawn that Darwinism exludes God and shows that man’s special status in creation is not only an illusion, but that mankind itself is inescapably bound up in the savage and bestial struggle to survive.
Clearly, Darwin himself was surrounded by an incoherent buzz of scientific and religious dogmatism and in light of this, the limpid nature of his observations should not be underestimated. What is remarkable, however, is how the observations and ideas this unassuming naturalist came to play such a profound role among the dialectical forces that drive modern history.
READING:
1. Jacques Barzun, Darwin, Marx, Wagner: Critique of a Heritage.
2. Charles Darwin, On Evolution
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