How Charles Darwin leveraged the Victorian age to discover and evangelize his theory of evolution
1. A family of Darwin scientists, the hub of his social network
While Gregor Johann Mendel’s family was stuck in generations of feudal serfdom and mud-groveling poverty, Charles Robert Darwin was born into a family that enjoyed generations of wealth and class privileges.
Charles’s father, Robert Darwin, was a physician and investor who married into one of the wealthiest families in the area. Robert’s wife Susannah was the daughter of Josiah Wedgwood, founder of the Wedgwood and Sons pottery company, famous for Wedgwood china and Staffordshire pottery, and still operating today (though now owned by other companies).
Darwin’s paternal grandfather, Erasmus Darwin, was a physician like his son Robert and his father Robert (there were a lot of Roberts and Erasmuses in the Darwin family tree). But Erasmus was also a natural philosopher who theorized about evolution, a slave abolitionist, inventor and poet. Erasmus’ father, Charles Darwin’s great grandfather, was the lawyer and physician Robert Darwin, who played a key part in bringing the very first fossil plesiosaur to the Royal Society in 1719. Robert did this by leveraging his contacts among his peers, namely William Stukeley, a physician and clergyman who was famous for doing the first scholarly archaeological studies of Stonehenge and other prehistoric monuments. So the interest in natural history ran like a current through the Darwin generations.
Unlike the young Mendel who attracted attention and opportunities for his intellectual abilities, the young Darwin was unpromising and mediocre academically (though remembered by his classmates and teachers for being very personable, if remembered at all). Darwin’s history with formal education was at best reluctant throughout his life and any of his teachers at any age would have failed to predict his success and contributions to academia and the world. In retrospect though, he thrived when learning on his own and clearly had an ability to concentrate his vast intellectual gifts on difficult problems and to solve many of them.
Charles was preceded by at least three generations of Darwin physicians, and his father clearly expected that he would follow suit. Robert sent Charles and his older brother Erasmus to the best medical school in the UK, the University of Edinburgh Medical School. But Charles neglected his studies, was repelled by surgery, and instead spent his time learning taxidermy from a freed slave (although Charles did not inherit an attraction to medicine, he did embrace the abolitionist tendencies among his extended and ancestral family members). Robert then sent his son to Christ’s College, Cambridge where again Charles spent most of his time riding and shooting and collecting beetles. He did eventually graduate with a Bachelor of Arts degree, and befriended several eminent naturalists. Darwin seriously considered a career in the clergy which would allow him to pursue is lifelong interest in natural philosophy…
2. Plugging into the Victorian social network
Darwin’s social connections and personable nature were the main things which gained him the opportunity to travel for five years (1831-36) aboard the HMS Beagle as a self-funded naturalist but really as a gentleman companion for Captain FitzRoy, a 23-year old aristocrat (4th great grandson of King Charles II) and a proven naval commander and surveyor. FitzRoy requested the position and vetted and approved Darwin personally. Specifically, FitzRoy requested a suitable gentleman companion who shared his scientific tastes, and would dine with him as an equal and a friend.
The moment the Beagle got under way, Darwin was sick, immobilized by nausea and misery. This was going to be a long five years. During his periods of incapacitation in his berth and workspace which he shared with another crewman, Darwin read. He trained himself to be a first-class geologist by bringing with him the first edition of Lyell’s Principles of Geology which taught that the current features of the planet were the result of constant small changes, like erosion, occurring over unimaginable periods of time. Vast amounts of time, much, much longer than the thousands or tens of thousands of years that biblically-informed speculators suggested as the total age of the earth. Darwin’s eventual conversion to Lyell’s uniformitarian theories (as opposed to the more biblically aligned catastrophic theories) planted the seeds in his mind of the enormous changes that could be wrought by small incremental steps over such deep time. Darwin’s observations and interpretations of geological processes such as mountain-building, and the formation of coral reefs and atolls (from corals building up around sinking volcanoes), were some of Darwin’s earliest and most impactful publications, long before his most famous book, On the Origin of Species.
Darwin was not isolated with a few shipmates for five years on the Beagle. He actually had a productive, though delayed, correspondence with his family, associates, and colleagues, throughout England and the Victorian world. England's global empire and its naval supremacy ensured that mail could get to and from most any part of the globe, and this was a network Darwin tapped into as well as anyone, especially during his scientific career.
Perhaps because of the intensity of his seasickness, Darwin actually spent most of his time ashore (three years and three months on land versus 18 months on board). FitzRoy had his assignments and used his surveying expertise to map the areas where they explored by sea. As FitzRoy made his way up and down the coast of any island or mainland, Darwin would bushwhack his way as far inland as possible and coordinate with the captain on where and when to meet up again.
During these on-land excursions especially as the Beagle poked its way around South America, Darwin geologized incessantly, observing, collecting, hypothesizing, and invariably some of the rocks he collected included fossils. Darwin’s other passion beside his newfound study of rocks, was his lifelong collection and study of living things, so he couldn’t help but note the similarities between some of these fossils and the local fauna…
3. Hit and near misses on the nascent theory of evolution
It is not clear exactly when Darwin began to piece together his own theory of evolution by variation and natural selection, but he had been exposed to various theories (such as those espoused by his grandfather Erasmus) as minority positions often disparaged by the mainstream creationists. But eventually the weight of his observations and collected data clearly contradicted the mainstream dogma of unchanging species and an earth whose age was measured in thousands of years. Darwin wrote in the opening paragraph of On the Origin of Species:
When on board H.M.S. ‘Beagle,’ as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relationships of the present to past inhabitants of that continent. These facts seemed to me to throw some light on the origin of species—that mystery of mysteries, as it has been called by one of our greatest philosophers.
Darwin was young when he started his world travels, the same age as FitzRoy (both about 23 when they left Plymouth Harbor). The vast array of observations and facts he collected impressed him deeply and influenced his work for the rest of his long life. But at the time of his travels on the Beagle, the facts were not yet stitched into a coherent theory of living things. This is evident in his sloppy collection of birds, especially the famous “Darwin’s finches”, from the various islands of Galapagos. If he had been more attuned to the possibility of evolution especially in relatively isolated islands, he would have more precisely recorded the locations from which the various finches were collected. He also didn’t realize at the time that the various bird species he collected on the islands were all different species of finches – he mislabeled some of them as mocking birds and other unrelated species. Years after the Beagle returned, and after he and FitzRoy fell into discord, he had to rely on the captain’s collection and better location labeling by his own servant, Covington, to help him build his case for evolution.
Two years after his return, and still before he had begun to form his theory of evolution, as he struggled to write and publish his many findings, Darwin happened to read Thomas Malthus’s An Essay on the Principle of Population. This influential book published in 1798 by the cleric and economist focused on the crush of overpopulation on the available supply of food. This turned out to be a critical piece of the puzzle which helped to unite the various disparate facts and the diversity of species he observed. Malthus’s book, though focused on human populations, impressed on Darwin how population pressures and limited resources such as food (and later mating partners and other constraints of survival and propagation) can apply a force for species change. The variations within a species provided the raw material for evolution, the transmutation of a species, but the force for change was the pressure to survive and reproduce amid limited resources. Variation and natural selection…
4. A long and leisurely gestation
Darwin was a deep thinker and a thorough scientist. He challenged and probed every aspect of his developing theory to the best of his ability. But it was not just his abilities he tapped into - he was not exactly a solitary genius (though he was certainly reclusive and social only when required). Darwin leveraged the global network of the British Empire, specifically the postal service, and communicated with a broad range of people from everyday farmers and breeders to the most eminent scientists and scholars of his day. He was like a spider at the center of its web, gathering facts and ideas from literally every corner of the world. He harnessed a very broad range of talents to his efforts to unravel the basic outline of evolution.
The thing is, Darwin did this not just for years, as might be expected for a well-researched topic. He did this for decades. Every answer had reasonable doubts – and unreasonable ones. He tried to address them all. And he probably would have gone on this way for decades more except that the unthinkable happened. A naturalist named Alfred Russel Wallace, with whom Darwin had corresponded briefly, was exploring in South America and Asia, and had stumbled on ideas of natural selection shockingly close to Darwin’s. Wallace wrote to Darwin about his theories, and Darwin was paralyzed on how to respond and behave. In the end, Darwin was a true gentleman, and gave Wallace the opportunity to share the stage with him, though still claiming primacy to the most thorough understanding of evolution.
Darwin’s former mentor and now friend and colleague, Charles Lyell, and other eminent scientists of the day, arranged for a public presentation of both their theories at the Linnaean Society in 1858
On the Origin of Species was published in 1859, twenty-three years after the Beagle returned Darwin to England…
5. The two giants, Mendel and Darwin
Darwin was able to shrewdly and effectively use his social standing, contacts, wealth, and fame (from his earlier works) to disseminate and even to somewhat control the narrative and discussion of his theory of evolution. He became even more famous and indeed a global celebrity in his own time. And while the resistance to evolution and natural selection continued strongly during his lifetime, it was clear that Darwin had made a tremendous and influential contribution right out of the gate. Darwin was an immediate success and powerfully influenced science during his own lifetime, something that eluded Mendel during his tragically short life.
One of the biggest problems with Darwin’s theory, however, was that he could not provide a mechanistic explanation for how variations and thus natural selection could happen. At the time there was no concept of genes, of mutations and alleles, leading to variations of traits within species. There were no known mechanisms to explain the heritability of trait variations which could then explain how natural selection forced a small incremental change to be passed on to the next generation. This is where Mendel’s own theories could have contributed, the principles of heritability that he deduced from his crosses of peas showing that traits independently assorted to the gametes, or sex cells, and that the factors carrying the trait came in pairs and were segregated from each parent into the gametes and then randomly combined in each offspring.
But Mendel’s principles of genetics were to remain obscured for almost half a century. It was not until the turn of the century, into the 1900s, before Mendel’s ideas began to be widely accepted, and thus to provide a strong foundation for Darwin’s own contributions.
Darwin and Mendel, for all their differences, are equally giants on whose shoulders every biologist past and present stands. These are the two who set the stage for the discovery of DNA, and the thriving science and discoveries around DNA that continue through today.
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If you have not already read the previous post on Gregor Mendel, please click on the following link:
Part 3 on Discovering DNA should be posted soon, so keep checking back. Meanwhile all the other posts are here:
A few helpful references on Darwin:
Browne, Janet (7 August 2003). Charles Darwin: Voyaging. Pimlico.
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