A century and a half has passed since Charles Darwin published On the Origin of Species, yet this book is still surrounded with controversy. It would not be an overstatement to say that the ideas of Charles Darwin on evolution sparked a revolution in human thought. But like most revolutionary ideas, Darwinism was, and still is, contested.

A recent New York Times article described the struggles of a science teacher in Orange Park, Florida, presenting evolution to a classroom of students, many whom believe in biblical creationism, the idea that all living creatures were each created separately by God.¹ The teacher’s careful strategy in presenting Darwinism in accessible ways that did not make his students feel their religion was threatened mirrored the manoeuvres Darwin himself made 150 years ago. Both plotted and schemed to ensure the theory of natural selection became the standard explanation of biological change. They were both motivated by a conviction that science should win over superstition. But they also were concerned with their reputation and sought to avoid conflict and controversy as much as possible.

Darwin’s theory of evolution asserted that new species arise through a combination of descent with modification and natural selection.² Darwin proposed that all life evolved from a common ancestor. The theory of natural selection is premised on a few key ideas: variability, scarcity, differential rates of survival and reproduction, and heritability, all of which result in natural selection.

The setting

Darwin has been called “the essential socially embedded scientist” by the eminent evolutionary biologist Stephen Jay Gould.³ Darwin’s social moment, the political and economic changes taking place around him, deeply influenced how he thought about the world and how he fought for the dominance of his ideas. This moment also made the widespread acceptance of his ideas more likely.

A quick glance at Charles Darwin’s family speaks volumes about the setting in which his ideas could take shape. Erasmus Darwin, grandfather to Charles, earned a living as a physician, but his lasting contribution was his materialist theories about evolution. At a time when England was politically dominated by the corrupt Anglican Church, Erasmus called even the reform-oriented Unitarian Church, “a feather bed to catch a falling Christian.”⁴ In his famous work Zoonomia, he asked, “would it be too bold to imagine, that all warm-blooded animals have arisen from one living filament, which the great First Cause endued with animality ... possessing the faculty of continuing to improve by its own inherent activity, and of delivering down those improvements by generation to its posterity, world without end?”⁵ This was heresy at the time, as the Anglican Church insisted that species were each created by God and that humanity was the special creation designed in God’s image for greatness above all animals.

The Unitarian Church, by contrast, was full of Whig Party political reformers opposed to slavery, and it argued that all things, including the human mind, were governed by physical laws, not divine whims.⁶ An influential portion of the rapidly rising business class of the early 1800s were Unitarians, and this rejection of the doctrines of the entrenched elites and the Anglican Church was one front in the larger battle waged between old and new during the Industrial Revolution.⁷ Charles Darwin’s maternal grandfather Josiah Wedgwood was one of these Unitarian merchants, still famous today for the fine china produced under his name. Although they never abandoned their fierce opposition to slavery, as the Wedgwoods grew in fame and wealth, they increasingly took on the mantle of Anglican respectability.

Charles’ father Robert was a renowned physician to those of wealth and privilege in the West Midlands region near Shropshire. Dr. Darwin sent his son Charles to Edinburgh University for his medical training and expected his son to return and take over his practice. But Edinburgh exposed Charles to a number of experiences that changed him forever. He encountered a group of radical thinkers at Edinburgh who had a lasting influence on his outlook. The Plinian society was a group of young devotees of natural history who were “fiery, freethinking democrats who demanded that science be based on physical causes, not supernatural forces”.⁸

Darwin left Edinburgh with all the most burning questions of the day in the front of his mind. He also was gaining an understanding of the discipline of science as more than just careful observation, but instead one of the many arenas in which political battles are waged. Given his love of natural history and his family’s interest in respectability, Charles decided that he must choose the profession that provided him the time and opportunity for both: the Church. His father pressured him to choose this avenue, reasoning that the church was the best place for his idle and aimless son.

The Anglican Church prospered luxuriously off of tithes and endowments, and a fine parish to oversee was often sold off at an attractive price to provide a calling for some second son. This was precisely the indolent and conservative route most resented by the free-thinking young men in Edinburgh. But Darwin was convinced that complete devotion to God was not a requirement of the job and he longed for a settled life as a gentleman naturalist. This shift sent him to Cambridge in 1828 to be educated to take the cloth.

During his studies, Charles absorbed himself in natural science, refining his lifelong love of collection, eventually creating an extensive collection of impressively mounted beetles. His devotion to natural history made him a favourite for the layer of professors who were gentleman naturalists themselves. Darwin added breadth to his knowledge of a variety of fields by striking up friendships with prominent professors Reverend Adam Sedgwick and John Stevens Henslow. These men trained him in geology, mineralogy, and botany with both private tutoring and fieldwork.

Voyage of discovery

In 1831, Darwin was given a rather prestigious offer by Captain Robert Fitzroy of the HMS Beagle to accompany him as a traveling companion (he later supplanted the ship’s official surgeon/naturalist, Robert McCormick) on a two-year survey of the South American coast.⁹ This came against the wishes of his family who saw the offer as a distraction from the clergyman’s life they wanted him to live. Although uncomfortable at the thought of disobeying his father, his excitement at the possibility of such an adventure eventually triumphed.

As much as he wanted to live a sensible and proper life in the eyes of his peers, the young Darwin felt a greater calling – that of science. Charles, packed with cumbersome scientific gear, notebooks, and sketchpads, became the official traveling companion to Captain Fitzroy. The journey, which actually lasted nearly five years, turned out to be a windfall for Darwin; he sent thousands of specimens back to England, making a name for himself as a prestigious naturalist within London’s scientific community. It was through examination of these specimens that he became convinced that evolution was the only reasonable explanation for the fossil record and ecological specialization of living species.

Darwin was determined to become a respectable gentleman naturalist. But his scientific theories were not compatible with the lifestyle he hoped for; evolutionists were radicals, part of the rabble. He initially settled on a London home but soon retreated to the relative seclusion of a home in Kent. He also found a respectable wife, his first cousin, Emma Wedgwood. Darwin then began the slow and patient process of refining and rephrasing his ideas to make them completely convincing and less controversial.

Darwin used his collections from the Beagle to build a reputation as a prodigious collector, naturalist, and geologist. He also outsourced some of the work of describing the specimens. Importantly, his bird collections from the Galapagos Islands went to the famous taxidermist John Gould, who informed him that what Darwin had assumed were a variety of different types of birds were, in fact, all finches. The example of the Galapagos finches was to be central in his later work on proving the evolutionary adaptation of organisms to their environment.

At this time the ideas of the East India Company’s economist, Reverend Thomas Malthus, were becoming in vogue among the Whig business classes. The East India Company was established to control exports from India on terms favourable to England. It came to directly rule large swathes of the country, exercising military power and assuming governmental functions. Malthus argued that population increases more rapidly than food supply, therefore a struggle for existence, with winners prospering and losers starving, was inevitable. Malthus also argued that any kind of welfare only prolonged the losing battle of the poor and retarded natural progress. These ideas found a happy home in certain segments of English society, especially the business classes, resulting in the Poor Law Amendment Bill that ended any relief for all but the most impoverished.¹⁰

Later, as a severe depression raged in the 1830s, the new Poor Law was introduced, which mandated harsher conditions in workhouses so they would serve as a deterrent for unemployment.

Although Darwin had already been exposed to Malthusian ideas, when he finally read the piece he was struck by the idea of competition for survival within a species. More specifically, it opened up his conceptual framework of biological life to the level of a mathematical analysis of population dynamics.¹¹ In developing his theory of natural selection, this level of analysis was the principle inheritance from Malthus.¹² The influence of Malthus has been overstated, however, as there is clear evidence from his notebooks that the essence of his theory was in place before he read Malthus’ “Essay on Population”. But the Malthusian struggle for survival was also attractive to Darwin politically. It allowed him a means to sell his evolutionary ideas as being far from the street radicalism that usually espoused it. Here was the way he could provide a devastating blow to creationism without losing potential allies.

“At last he had a mechanism that was compatible with the competitive, free-trading ideals of the ultra-Whigs. The transmutation at the base of his theory would still be loathed by many. But the Malthusian superstructure struck an emotionally satisfying chord; an open struggle with no handouts for the losers was the Whig way … He had broken with the radical hooligans who loathed Malthus … From now on he could appeal to a better class of audience–to the rising industrialists, free-traders, and Dissenting professionals.”¹³

Theory revealed

For the 20 years following 1838, Darwin patiently collected a group of fellow scientists whom he won to his evolutionary views but who were not beyond the pale, radical democrats. Botanist John Hooker and the comparative anatomist Thomas Henry Huxley were, over a period of years, won to Darwin’s side, although Huxley disagreed with Darwin on some of the details.

Darwin’s 20 years of careful planning and positioning came to an abrupt end when the geologist Charles Lyell informed Darwin that the English naturalist and explorer Alfred Russel Wallace had hinted at a mechanism for natural selection in a recent article.¹⁴ Finally, Darwin told his friend his full theory, and although Lyell was deeply shaken by the implications, he pressed his friend to publish his ideas before Wallace beat him to the punch. In 1858, after Darwin had already compiled massive amounts of evidence for natural selection, he received a letter from Wallace that laid out an almost identical theory, although it was much less well supported than the examples Darwin had amassed over the years.

Despite his desire for acclaim, Darwin placed the quandary of independent discoveries of natural selection in the hands of his scientist friends. Hooker and Lyell arranged for a joint paper and presentation to the prestigious Linnaean Society. The presentation was met with stunned silence, as much in response to the tacit approval shown by Lyell and Hooker as by the evolutionary content of the paper. It took over a year for Darwin to whittle down his writings on evolution to a publishable abstract. This volume came to be known as On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. During this time, both the anti-evolution camp and Huxley, Hooker, and company were organizing, gathering supporters, planning meetings and presentations, and preparing for the storm. The first edition numbered 1250 copies in November 1859 and by January, a second edition of 3000 copies was flying off the stands.

The lines were drawn around Darwin’s Origin: the Unitarians and reformers loved it, while Darwin’s Cambridge mentors with their Anglican respectability loathed it. The battle raged for some time, but the tide had clearly turned as the most respected of the young generation of scientists began to cohere around Darwin’s mountain of evidence for the theory. Darwinian evolution was used as a lever against the crusty gentleman naturalists who had dominated the discipline for so long. Darwin continued to update new editions of Origin, six in total (with only the fifth and sixth editions using the phrase, coined by Herbert Spencer, of “survival of the fittest”).

Darwin’s theory of evolution by natural selection was shaped by social and political factors, and in turn shaped them. Clearly, the history of biology has two eras – before and after Darwin. However, the field of evolutionary biology has, appropriately, not remained static. While elaborations and expansions of Darwin’s central themes about biological change occur constantly, one of the most significant contributions to evolutionary biology, the theory of punctuated equilibrium, was considered by some to be an attack on Darwin’s theory of evolution, specifically his emphasis on gradual change.¹⁵ Darwin’s work stresses the very slow, progressive nature of the changes that occur among biological life. Darwin’s strongest influence in this was his mentor Charles Lyell, who wrote the amazingly rich volume Principles of Geology.

Lyell emphasised uniformity of process and the slow rate of geological change. Lyell argued that only the processes at work on the Earth today were those that shaped its natural history, thus ruling out catastrophic or accelerated change. While his materialist, as opposed to supernatural, explanations for the contours and features of the earth was progressive, his single-minded insistence on gradualism was not as healthy for the scientific community. Stephen Jay Gould points out that Lyell’s insistence on uniformity of process has, “complex roots. In part, Lyell merely ‘discovered’ his own political prejudices in nature – if the Earth proclaims that change must occur slowly and gradually … then liberals might take comfort in a world increasingly threatened by social unrest.”¹⁶

In the realm of biology, the idea that all change, including speciation, must be gradual has also been challenged by a layer of dialectical biologists, among them Gould himself. These biologists, in addition to emphasizing the way in which social conditions and class interests shape scientific inquiry, consciously apply dialectics to scientific questions. A dialectical approach to natural phenomena sees them not only in constant motion and change, but that change is the product of contradictory forces, and that the quantitative, gradual changes can also give way to breaks in continuity or to qualitative leaps.

Gould and his collaborator, Niles Eldredge, used this approach to take a fresh look at the fossil record in the 1970s.¹⁷ After years of searching for the missing gradual steps between what appeared to be explosions of new species and mass extinctions, they concluded we should accept the simplest explanation of the evidence. They put forward the theory of punctuated equilibrium. This theory claims that natural history of any particular species is characterized by long periods of relative stasis, or “equilibrium”, which are then “punctuated” by periods of rapid change.

This theory of punctuated equilibrium was an elaboration on Darwinian evolution in that it still uses natural selection as its method of adaptive change and asserts that most periods are characterised by non-directional change (equilibrium). But the punctuation proposed was strongly outside the Darwinian tradition. The question is, why? York and Clark argue: “The preference for gradualism common in the natural sciences … cannot be justified on scientific grounds. Rather, to some degree at least, it reflects a social bias, likely stemming in part from an ideology of the social elite, for slow, predictable change and against the notion that dramatic historical change occasionally occurs in brief, revolutionary moments.”¹⁸

The 150th anniversary of the publication of On the Origin of Species occurs this year. The ideas presented therein both resulted from, and in turn caused, huge shifts in the way we view the world. According to Gould, “Darwin was a gentle revolutionary. Not only did he delay his work for so long, but he assiduously avoided any public statement about the philosophical implications of his theory.”¹⁹ Yet Darwin’s ideas were revolutionary, and their implications are still seen by many as threatening today.

“Why does Darwinian evolutionary theory remain so hard for so many to accept”, writes Richard York, “even though the scientific evidence in support of it is as firmly established as that for the Copernican theory of the heliocentric solar system (which dethroned the earth as the center of the universe), which no one has seriously suggested be excised from school curricula? The materialism inherent in the theory, which obviates the arguments for a ‘higher’ meaning or purpose to the universe and life, is surely the aspect many people find the most unpalatable … Darwin vanquished the opponents of reason in the last great intellectual battle of the Enlightenment … showing how the magnificence of life itself could be explained by natural causation, without the invocation of supernatural forces. In this, he shared much with Karl Marx, who sought to understand the world and the human place in it without recourse to irrationalism, philosophical idealism, or theism.”²⁰

Darwin also argued against a static conception of the natural world, overturning in biology the remnants of the static biblical formulation, “At the time of creation God created them all, each after its kind”. Karl Marx’s collaborator Frederick Engels put it this way: “Nature works dialectically and not metaphysically … she does not move in the eternal oneness of a perpetually recurring circle, but goes through a real historical evolution. In this connection, Darwin must be named before all others. He dealt the metaphysical conception of Nature the heaviest blow by his proof that all organic beings, plants, animals, and man himself, are the products of a process of evolution going on through millions of years.”²¹

1. Amy Harmon, “A teacher on the front line as faith and science clash”, New York Times, August 24, 2008.
2. Charles Darwin, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life (London: John Murray, 1859), 119.
3. Quoted in Adrian Desmond and James Moore, Darwin: The Life of a Tormented Evolutionist (New York: W. W. Norton & Company, 1991), i.
4. Ibid., 5.
5. Erasmus Darwin, Zoonomia (Philadelphia: E. Earle, 1818), 397.
6. John Seed, “Unitarianism, political economy and the antinomies of liberal culture in Manchester, 1830–50”, Social History 7.1 (1982): 1–25.
7. Ibid.
8. Desmond and Moore, Darwin, 31.
9. Stephen J. Gould, Ever Since Darwin (New York: W. W. Norton & Company, 1977). 28–31.
10. Desmond and Moore, Darwin, 169.
11. John Bellamy Foster, Marx’s Ecology (New York: Monthly Review Press, 2000), 186–87.
12. Silvan S. Schweber, “The origin of the Origin revisited”, Journal of the History of Biology 10 (1977): 229–316.
13. Desmond and Moore, Darwin, 267.
14. Ibid., 438.
15. Richard York and Brett Clark, “Natural history and the nature of history”, Monthly Review 57.7 (2005): 21-29. Stephen J. Gould makes the same point in his essay, “Uniformity and catastrophe”, in Ever Since Darwin, 147-52.
16. Gould, Ever Since Darwin, 12–13, 192.
17. Niles Eldredge and Stephen Jay Gould, “Punctuated equilibria: an alternative to phyletic gradualism”, in Models in Paleobiology, ed. T. M. Schopf (San Francisco: Freeman Cooper, 1972), 82–115.
18. York and Clark, “Natural history and the nature”.
19. Foster, Marx’s Ecology, 192–94.
20. Richard York, “Darwin’s materialism”, Monthly Review 57, no. 11 (2006): 56–60.
21. Frederick Engels, Socialism: Utopian and Scientific (New York: Mondial, 2006), 48.

[Abridged from International Socialist Review, bi-monthly magazine of the US International Socialist Organization. Rebekah Ward is an author, activist, and postdoctoral fellow in the Department of Microbiology and Immunology at Emory University, Atlanta.]