November 1859 saw the publication of Darwin's highly controversial theory on evolution. Martin Charlton looks back on his legacy
Ask people to name a place associated with Darwin’s theory of evolution, and most will probably say the Galapagos Islands. However, they were, like the other locations Charles visited aboard HMS Beagle, only the seeds to what would become the most controversial theory in human history.
A catalyst was needed, something or somewhere to allow those ideas to germinate, and in 1842, Darwin found it in the form of Down House, in the village of Downe near Orpington. Here, in his garden and the surrounding countryside, he noticed the same struggle for life that he had observed around the world.
Over the next 20 years, he would conduct a number of experiments on animals and plants, the result of which would be the publication of On the Origin of Species by the Means of Natural Selection in November, 1859. But even after the book’s publication, he continued his experiments, for he knew that his theory had a number of holes; holes that would be — and still are being — filled by latter generations of scientists.
It was while living in London that Darwin began to question the accepted view of how life was created. In 1838, he read Thomas Robert Malthus’s Essay on the Principle of Population (1798), which stated that the human population increased faster than the means to support itself. Darwin took this theory and applied it to the natural world, determining that, in hard times, only the strongest survived and the weak perished. He called it natural selection.
By the summer of 1842, he had sketched out the main outline of this evolutionary theory. However, it was still hazy and, without sufficient scientific evidence, it would not stand closer scrutiny. The hustle and bustle of London made it difficult for him to concentrate on his ideas. He also had a young family and their home in Bloomsbury had become inadequate.
With financial help from his father, Charles moved his family to Kent, but the move was soon blighted by the death of two of his children (for more on Darwin’s home life see Bygone Kent, Vol 30 No 2).
Darwin set about gathering the scientific evidence needed to justify his theory. He turned the house and its garden into a living laboratory, observing, recording and interpreting everything he saw. His study was a strange mixture of mahogany furniture, brass microscopes, instruments for dissecting, and piles of specimens and papers. From here, he corresponded with a variety of people: philosophers, scientists, mariners, breeders — anyone who could offer the relevant information needed.
He was particularly interested in the varieties of domesticated animals, such as dogs and pigeons, and in the way that breeders chose a particular characteristic and enhanced it in subsequent generations. This prompted him to wonder if the same process existed in nature and, if it did, then it must happen over a considerable period of time — which meant that the Earth was far older than the 6,000 years claimed by theologians.
One of his experiments on plants consisted of soaking seeds in saltwater for a month, then sowing them to see if they would still germinate. Some did, and this showed that it was possible for the seeds of certain plants to cross on ocean currents and colonise new lands, evolving into new species. Another involved removing a square section of his lawn, and leaving the bare earth to the elements. Darwin then recorded the number of seedlings that germinated, noting which survived and which perished.
He started breeding pigeons and primulas, observing and hoping that the characteristics he wished to develop would show in the offspring. The garden began to fill with all manner of contraptions used to measure the growth of animals and plants, including netting and muslin sheets to keep off pollinating insects, cloches for controlled plant growth, and accoutrements to keep pigeons and rabbits.
As was the custom of middle-class Victorian Britain, the Darwins entertained during the weekends. Among the guests was Sir Charles Lyell, author of Principles of Geology (1830), a book that had greatly influenced Darwin. In it, Lyell expressed the view that the Earth changed in a slow and uniformed manner, which caused Darwin to wonder what effects these changes would have on local biology.
What impact — if any — did the environment play on the development of species? What amounts of time were needed for evolutionary change to occur? Was it gradual or something that happened after a catastrophic event? Or were people like Richard Owen (1804–1892, founder of the Natural History Museum and a creationist, known for his outspoken opposition to Darwin’s theory) right in their belief that species appeared fully formed?
When his weekend guests had departed, Charles would return to his solitude of work and thought. During those early years at Down House, he wrote his species theory, in essay form, as well as working on other papers. Darwin then sealed it in an envelope, locked it away in the drawer of his study, and left a set of instructions to his wife on how to handle its publication on the event of his death.
With each new insight into the natural world, he became more anxious about the impact that his theory would have on the rest of society, as well as the reaction of friends and scientific colleagues. Not confident that he had enough evidence to support his ideas, he wrote: “I cannot possibly believe that a false theory would explain so many classes of facts, as I certainly think it does explain. On these grounds I drop my anchor, and believe that the difficulties will soon disappear.”
He continued with his experiments and observations of the wildlife in his garden and the surrounding countryside, and in 1846, turned his attention to the life-cycle of barnacles. Over the next eight years he dissected, examined and classified thousands of specimens, some sent to him from all round the world. The work was painfully slow, and his health, already fragile, began to suffer terribly.
Barnacles are found on almost every shoreline worldwide, and Darwin discovered that they had all evolved from a common ancestor. He wrote a two-volume book on them — leaving out their evolutionary ancestry — which won him the Royal Society Medal in 1854.
However, during the course of this research, tragedy again struck the family. In spring 1851, Darwin’s eldest daughter, Annie, died from a “bilious fever with typhoid character”, aged 10. For Charles her “bitter and cruel” death destroyed any remaining belief in a moral, just, universe.
Darwin’s eureka moment came in May, 1855. He was travelling from Orpington station back to Downe by cab, when he ordered his driver to stop. He leapt out, shouting: ‘I know it! It’s going to work.’ He had been watching the countryside when it finally dawned on him how all the animals and plants were ‘bound together by a web of complex relations’. He observed how bumblebees alone visited the flowers of red clover, because other bees could not reach the nectar. His research showed that two thirds of bumblebee nests were destroyed by field mice, except around farms and villages where domestic cats kept the mice under control. In places where there were no cats, there was little or no red clover, concluding that the survival of one species depended on the survival of another.
He began sorting his notes for his “species theory”. Aided by his friend, Thomas Huxley, he also began studying the fossils of prehistoric horses, and was able to follow its evolutionary progress from the small four-toed Eohippus of 55 million years ago up to the modern horse.
Then, on 18 June, 1858, he received a package from Ternate, a small island near New Guinea. Inside was a manuscript written by Alfred Russell Wallace, who had also read Thomas Malthus’s Principle of Population. Wallace put forward the same idea of natural selection, so, worried that someone else was about to steal his thunder, Charles quickly wrote On the Origin of Species. John Murray published it on 22 November, 1859, printing 1250 copies. Costing 14 shillings, it became an international bestseller and has never been out of print.
Among those who criticised it was Richard Owen. In an anonymous review in the Edinburgh Review of March, 1860, he tore the book to shreds, considering it an ‘abuse of science’ and ‘a degradation’. His greatest disgust, however, was the notion that man had descended from mere animals, although it is a misconception that Darwin stated in the book that man had evolved from apes. In fact he wrote: ‘Light will be thrown on the origins of man and his history.’
The creationists also argued that if one group of animals could indeed evolve into another, then where was the evidence of intermediary species? In a historic twist of irony, it was Owen himself who supplied such evidence when, in February, 1862, he purchased the first Archaeopteryx, which had been discovered in a German quarry. Here was a creature that had both reptilian and avian features, and today the fossils are still hotly debated among scientists as to whether they belong to a dinosaur or an early species of bird.
For Darwin and his followers, it was physical proof of how some animal species can evolve into new and different forms. There were still many unanswered questions, but Charles believed that they would be answered by future generations of scientist.
After the publication of On the Origin of Species, Darwin went back to his experiments, studying the sex life of orchids, the eating habits of carnivorous plants, and the intelligence of garden worms. He also went on to write other papers and books, such as The Descent of Man (1871), in which he dealt with human evolution, and The Expression of the Emotions in Man and Animals (1872), which was one of the first books to be published with photographs.
He died while walking in Downe on 19 April, 1882. Charles had wanted to be buried in the village churchyard, but was instead given a state funeral at Westminster Abbey, and interred near to Sir Isaac Newton.
The man was dead, but his theory lives on, forming the bedrock for varieties of new science, such as ecology and genetics. Evolution changed how we perceive the natural world — it was big enough to undermine creationist thinking, but simple enough to be stated in a sentence.
However, during the early part of the 20th century, philosophers and politicians hijacked the theory. Eugenics was a movement concerned with the betterment of human society by allowing only those considered genetically fit to breed. Anyone who was disabled or deemed simple-minded would produce inferior offspring and, in America, a number of people were legally sterilised for this reason until the 1970s.
This was the dark side of Darwin’s dangerous idea, and it was set to get darker with the mass murder of millions of Jews, homosexuals, gypsies, political dissidents, and anyone else the Nazis didn’t like. It was only after the formation of the United Nations that evolution was clawed back from the extremists to form the founding idea behind the Declaration of Human Rights. Charles believed the human race to be one species, so every man was equal.
Whether we like it or not, Darwin’s theory of evolution through natural selection has influenced every part of our lives. It has shaped the way we see ourselves, our place in society, our beliefs, and our place in the natural world. It is as hotly debated today as it was a century and a half ago, and will probably be so for years to come. But as Darwin himself once said: “Freedom of thought is best promoted by the gradual illumination of men’s minds, which follows from the advance of science.”