Context
Charles Darwin (1809-1882) was a naturalist and evolutionary biologist. He lived during the Pax Britannica when the British navy became the dominant european force. The UK held colonies in India and Australia as well as informal commercial ties in the Mediterranean, East Asia and South America.
It was the materials and exchange with these markets that helped to sustain the industrial revolution. This ensured more productivity and cheaper consumer goods for the population, but also social disruption and poverty among the exploited factory workers. Political changes accompanied technogical progress and restrictive Poor Laws and workhouses were designed to hold political activism at bay. Capitalist factory owners gradually replaced landowners in Parliament and electoral reforms were introduced. 50 years after the 1832 electoral Reform Bill the right to vote rose from 3% of the population to 60%. Material progress also encouraged the middle classes to cultivate their interests in artistic and scientific projects and Darwin benefitted from the latter. Dickens summarised this Victorian era as:
“It was the best of times, it was the worst of times.” (A Tale of Two Cities)
In 1831 Darwin embarked on the HMS Beagle in a five year surveying voyage to South America and New Zealand.
The biologist was on board as gentleman's companion to the captain, Fitzroy. Darwin was a self-supporting scholar, like many budding scientists of his time who pursued their interests backed by family wealth. Victorian Britain understood scientific pursuits as informed by natural theology, that is, a quest to comprehend God through his Creation. This conservative idealism concept opposed a more materialist approach inspired by the empiricist tradition and the French Enlightenment. Much of the frenzy over Darwin's On the origins of species was the result of a philosophical clash between these binary attitudes to scientific discoveries, especially as the science departments in British universities were controlled by clerics.
Darwin returned from his Beagle voyage in 1838. British society had been upturned by the Industrial Revolution, making capitalists very rich while the many workers needed Welfare to survive. Critics maintained that the Poor Laws to sustain the needy would only lead to increased dependence and encourage childbirth, leading to more hungry people.
In an attempt to comprehend the social situation Darwin read Thomas Malthus, a political economist. In An Essay on the Principle of Population (1798) Malthus argued that populations increased exponentially, whereas resources increased linearly. Applied to society this suggests that more resources would result in population growth, not in improvement in socioeconomic conditions. Malthus concluded that the number of children should be restrained or the scarcity of food woukd lead to a struggle for existence because of the growing population. Darwin applied these ideas to the Nature where there is no restraint. He realised that when animal populations bred beyond their food sources, there would be losers and also survivors. The latter would be the better suited in the struggle to survive. He then saw that the survivors would leave more offspring than the losers and would eventually dominate the population in the form of a new species. This was his theory of natural selection, explained in On the origen of species:
"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. As many more individuals of each species are born than can possibly survive; and as, consequently, there is a frequently recurring struggle for existence, it follows that any being, if it vary however slightly in any manner profitable to itself, under the complex and sometimes varying conditions of life, will have a better chance of surviving, and thus be naturally selected. From the strong principle of inheritance, any selected variety will tend to propagate its new and modified form."
Malthus's theory about the struggle for survival probably foreshadowed Darwin's theory of competition in the natural world.
Summary
On the Origin of Species by Means of Natural Selection of the Preservation of Favoured Races in the Struggle for Life was published in 1859.
In the Introduction the author tells of formulating his theory while voyaging on the Beagle and drafting some conclusions in a journal before having evidence. He explains that he had not published previously because of fear of public rejection. He had only gone to print when he received a letter from Alfred Russell Wallace outlining similar findings.
Chapter 1 offers an illustration of his ideas with the example of domesticated plants and birds, like pigeons. Humans breed them for certain characteristics in a model Darwin names artificial selection.
Chapter 2 focuses on the great individual variability in plants and animals. He asserts that the same species generates more variation in a wide geography than in local areas.
Chapter 3 examines the “struggle for existence.” On reading Malthus the author realised that more progeny are born than reach adulthood. This results in competition for resources, fiercest among members of the same species.
In Chapter 4 there is a full description of natural selection. He demonstrates how this principle works across all species, how it explains extinction and the variation in modern forms. He presents the concept of sexual selection and the competition for mates.
Chapter 5 examines possible causes for natural variation. He admits that the Lamarkinan model of 'use and disuse' may explain this. Flightless birds, for example, may have become so for not using their wings over time. (Modern genetics have shown that the correct explanation is natural selection, not use and disuse.)
In the following chapters he examines the weak points in his own theory.
Chapter 6 recognises the problems in finding fossils in a good state. He also questions the evolution of eyes and the changes involved in mammals moving from land to water. These seem too complex for transformation through natural selection.
Chapter 7 notes that complex instincts such as honeycomb production by bees are difficult to explain through natural selection. However he bases his reasoning on individual variations which may account for natural selection.
Chapter 8 analyses hybridism and how related species are crossbred, resulting in sterility.
Chapter 9 relies on Lyell's geological work to comprehend the great age of the earth and its changes, as well as the defects in fossil records.
Chapter 10 reiterates imperfections in the fossil record but emphasises that the fossils in hand point to natural selection.
Chapters 11 and 12 examine the distribution of plants and animals geographically. He demonstrates how natural barriers contribute to new species and viceversa, using the Galapagos Islands as examples.
Chapter 13 considers how people catalogue species by similarities which reflect biological links. He also refers to anatomical and embryonic similarities.
Chapter 14 is a summary of the main points. In his conclusion he allows that the Creator may have breathed life into the first organism and that a natural process took over after that.
Themes
Natural selection
The scientific controversy in the middle of the 19th. century was about how species became so varied. Some believed that each species was created individually, probably by God, and that they were immutable. Darwin, as a devout Christian, did not dispute divine creation but suggested that all species descended from a few, or even one, ancestor.
"I have called this principle, by which each slight variation, if useful, is preserved, by the term of Natural Selection."
This concept was not new in the 19th. century and had been defended by Erasmus Darwin, his grandfather, Lamarck and even voiced by Anaximander.
However, in the second part of his theory Darwin believed he had discovered the mechanism which generate variation in species: the struggle for existence and the survival of the best adapted to the environment. He called this cause of variability natural selection.
Following Darwin's theory all life is immersed in a struggle to survive due to limited resources. The plants and animals which best adapt to their environment have the best chance of survival and will pass this on to their descendants. As the living things adapt to survive it can become a new variety, or a new species. Given a huge timescale this natural selection may account for the great diversity of species, without divine intervention.
Scientific methodology
Darwin's book, On The Origin of Species, sets out to convince the reader through reasoned arguments about the theory of natural selection. Knowing that religious people in particular would disagree with his theory, the author devotes many sections of the book to answering criticisms, using hard evidence:
"I have steadily endeavoured to keep my mind free so as to give up any hypothesis, however much beloved (and I cannot resist forming one on every subject), as soon as facts are shown to be opposed to it."
Darwin relied on observation and experimentation throughout the book, particularly his experiences on the Beagle, to support his argumentation. He also used the efficient Victorian postal service to obtain specimens from around the world.
His reasoning is inductive, unlike the deductive assumptions of his critics. Darwin constructed his arguments methodologically: identification of possible criticisms, recognition of their value, proposal of evidence to surmount the objections. The whole work was based on reason as a fundamental value in understanding Nature. On the Origin of Species demonstrated how science possesed the tools for the discovery of truth.
Adaptability
One of the principal ideas in Darwin's book was that, given time, living things constantly adapt to their habitat. The less adapted organisms die out and those that survive do so because they fit in with their environmental resources. The author believed that even complex structures like the skull, the eyes and wings could evolve from simpler ones. Adaptation is a complex process, since changes in the environment and in other species also require plants and animals to self-adjust.
"It is not the strongest of the species that survives, not the most intelligent that survives. It is the one that is the most adaptable to change."
Nature is not immutable but, on the contrary, ever-changing. Since variation is random and unpredictable it occurs incrementally over extended periods. However natural selection creates species which are always better adapted, never less adjusted to their environment than their ancestors. Darwin's theory presents the evolutionary process as positive with species always perfecting adaptation.
Collaboration
Darwin presents the concepts in his book as ideas learned from other scholars. This is partly an argumentative strategy which bolsters the acceptation of his theory and minimises his personal implication in it.
However it is also clear that the author relied on experts in other fields for evidence of his natural selection hypothesis. Charles Lyell's geological discoveries were of importance to Darwin in comprehending how natural selection worked over time. In later editions Darwin acknowledged criticism of his own model and its deficiencies and answered his critics' questions.
He also recognised in the Introduction that Wallace, who had provided him with evidence, had had the same insight as himself. Both men had been inspired by Malthus' observation that individuals compete for limited resources. It was through scientific collaboration that the brilliant theory of natural selection came into being.
Social Darwinism
Darwin's theory of natural selection focused on giving a scientific explanation to observations on plant and animal diversity. He proposed that only those best adapted to their environment would survive to have offspring and so transfer their genes. The others would die off.
When attempting to communicate his ideas to the public Darwin adopted well-known concepts such as Herbert Spencer's "survival of the fittest" and Malthus' "struggle for existence". Followers of Spencer and Malthus seized on darwinian theory to confirm the protestant ethic beliefs about society described by Max Weber: the fit had the inherited, and God-given, qualities of diligence and capacity to enrich themselves; the unfit were sluggish and foolish.
Spencer himself applied Darwin's theory to economics to support Adam Smith's laissez-faire capitalism, where government regulation is minimised. Unlike Darwin, Spencer asserted that morality and frugality could be genetically inherited. He opposed the Poor Laws to support the exploited working class during the Industrial Revolution. According to him this help would only prolong the life of the "unfit" and impede the evolution of civilisation. (This concept was implemented as policy by the 1980s Thatcher government in the UK naming the unemployed "scroungers".)
Another famous social darwinist was William Graham, a US economist, author of Sociology (1881). He opposed the welfare state, viewing competition for property and status as a way of eradicating the less able and immoral in society.
Francis Galton, Darwin's half-cousin, presented a novel concept to improve the human race which he called eugenics. He proposed to better humanity by spreading the British elite. He maintained that welfare and asylums helped inferior people to reproduce more than their higher class compatriots. Eugenics was embraced in the USA, and previous to 1950 thirty-two States sterilised over 64,000 citizens deemed 'unfit' to have children.
Adolf Hitler began to read about social darwinism during his emprisonment after the failed Beer Hall Putsch in 1924. He believed that the German master race had grown weak because of non-Aryans in Germany. It became necessary to purify the gene pool. The inferior races were targeted for extinction: Jews, Roma (gypsies), Poles, Soviets, the handicapped and homosexuals.
After World War II eugenics was decried as completely unscientific.
Influence
A new science was founded through Darwin's scholarship: evolutionary biology. He contributed to this science in several ways: the idea of the evolution of species; the common descent of all organisms; the gradualism of evolution; the mechanism of natural selection.
Darwin also contributed to a new branch of the philosophy of science: the philosophy of biology. His contribution was to include historicity in science. This means that the biologist must explain events in time. This involves constructing a historical narrative to account for the events observed. For example the extinction of the dinosaurs had three competing explanatory narratives: an epidemic, climate change and an asteroid impact. The last account is now accepted as best fitting the evidence. Experimentation takes second place in evolutionary biology, eclipsed by classification, comparison, observation and assessment of historical accounts.
The philosophy of final causes, which guided teleological thought from Aristotle onwards, was also discarded in favour of a new vision: natural selection. There is no ultimate purpose and no predetemination, just the struggle to adapt, which is both random and necessary. It can be argued that Darwin's theory also led to the understanding of the genetic programmes common to all living organisms, and which are the result of natural selection. These activities are governed both by the universal laws of physics and chemistry and by a genetic program, itself the result of natural selection, which has molded the genotype for millions of generations.
Darwin has also influenced the modern secular worldview. In his time philosophers and scientists held Christian values. The world was a creation of God. Contrary to this the author explains natural phenomena avoiding all supernatural references. His theory of natural selection is purely materialistic and excludes God as Creator. This positivist outlook encouraged a strictly scientific account of Nature, a thinking revolution which still affects us today.
Dating from the ancient Greeks the idea of diversity underlined its essence, stability and invariability. Darwin's concept of variability is accidental, not essential. Essentialism in biology has led to the inability to integrate variability so that, for example, the typology of human races arose where Caucasians, Africans, Asians or Inuits were considered different ethnic groups. This encouraged racism. Darwinian thinking introduced the concept of population where each human is different because varieties in populations are not judged through their essences, but statistically. This change in perspective allowed science to conclude that there is only one human race, thus preempting racist theories.
Through natural selection Darwin introduced the modern concept of universal randomness, contradicting the idea of determinism held until then. This is true, of course, only for the production of variation, since the second step in natural selection is directional. Physicist nowadays accept the notion of contingency and chance in natural processes, so much so that many biologists reject universal laws in their subject and rely on probabilities. (Probability was to become the basis for quantum mechanics in the 20th. century, in spite of Einstein's objection that "God does not play dice with the universe.")
Darwinian theory provided a new view of humanity's place in the natural world. The philosophy and theology of his time believed that humans held a unique position as regards their origin, made in the image and likeness of God, according to Genesis. Aristotle, Descartes and Kant agreed on this. However, evolutionary studies demonstrate that humans have a common ancestry with apes. This has deprived humanity of its unique position.
"Man is descended from a hairy, tailed quadruped, probably arboreal in its habits."
Darwinism has provided a base for ethics, too. In The Descent of Man (1871), the author applied the concept of selection, not only to the individual, but also to the group. The cooperation within the group is a crucial element in its survival and development. This conduct has its base in altruism, which in turn favours the individuals of the group. This adds up to a natural selection of altruistic behaviours which appears to favour cooperation in social groups. This vision was adopted in the 21st. century by Noah Harari in Sapiens: A Brief History of Humankind.
"In the long history of humankind (and animal kind, too) those who learned to collaborate and improvise most effectively have prevailed." (2011)
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