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8 April 2020

The Brilliant Plodder

David Quammen

Charles Darwin is ever with us. A month seldom passes without new books about the man, his life, his work, and his influence—books by scholars for scholars, by scholars for ordinary readers, and by the many unwashed rest of us nonfiction authors who presume to enter the fray, convinced that there’s one more new way to tell the story of who Darwin was, what he actually said or wrote, why he mattered. This flood of books, accompanied by a constant outpouring of related papers in history journals and other academic outlets, is called the Darwin Industry. 

There’s a parallel to this in publishing: the Lincoln Industry, which by one authoritative count had yielded 15,000 books—a towering number—as of 2012, when an actual tower of Lincoln books was constructed in the lobby of the renovated Ford’s Theatre, the site of his assassination, in Washington, D.C. It rose thirty-four feet, measured eight feet around, yet contained less than half the total Lincoln library. You could think of the Darwin library as a similar tower of books three stories high, big around as an oak, festooned with biographies and philosophical treatises and evolutionary textbooks and Creationist tracts and the latest sarcastic volume of The Darwin Awards for suicidal stupidity and books with subtitles such as “Genetic Engineering and the Future of Humanity.” Janet Browne’s magisterial two-volume life would be included; so would David Dobbs’s Reef Madness, about Darwin’s theory of the formation of coral atolls, and a handful of books on the Scopes trial. Lincoln and Darwin were born on the very same date, February 12, 1809: a good day for the publishing business. 

One lesson from all this is that Darwin’s name sells. A less mercantile way of viewing it is that Darwin’s name stands for what Daniel Dennett has called “the single best idea anyone has ever had,” and therefore serves as a portal to scientific and philosophical ruminations of vast depth and breadth. We can’t stop reading and talking about Darwin, 138 years after his death, because the great theory of which he was co-conceiver (with Alfred Russel Wallace) and chief propounder (in On the Origin of Species) was so big and startling and forceful, yet so unfinished when he died in 1882, that there’s always more work to do. We’re still trying to figure out how evolution by natural selection—Darwin’s dangerous idea, in Dennett’s phrase—applies to every aspect of life on Earth, from virulence in coronaviruses to human social behavior. It takes a lot of books to follow all those tendrils out to their end points, and a lot of other books to examine Darwin’s digressions and lesser fancies (pigeon breeding, the taxonomy of barnacles, the facial expressions of orangutans, climbing plants), his place in scientific history, and his continuing influence on how we understand the living world and humanity’s place within it. 

Each of the three new books considered here offers a unique slant on Darwin. The least controversial of them is Ken Thompson’s Darwin’s Most Wonderful Plants, a survey of the botanical experimenting and theorizing that occupied Darwin’s golden years. This little volume proceeds from Virginia creepers to sundews to orchids to pansies, all as gently as a Sunday garden tour, but with expert evolutionary commentary, and it is garnished by Thompson with some odd facts about plant evolution that Darwin might have considered but didn’t. It’s a glimpse of Darwin the country squire, Darwin the horticulturalist, an old man pottering in what Thompson calls “the cabbage patch”—or think of Don Corleone amid the tomatoes. It contains the fine sentence, “Of course, any fool can be impressed by a Venus flytrap,” and adds contrastingly that “Darwin’s genius was to see the wonder, and the significance, in the ordinary and mundane.” Monitor the weed seedlings coming up on a patch of bare ground during March and April, for instance, and you might find that by May three quarters of them have been killed, chiefly by slugs—the struggle for existence. 

Darwin’s gardening was no frivolous hobby because it involved serious buttressing of his theory. From it came no fewer than six books, plus parts of a seventh. The last of them, published two years before his death and titled The Power of Movement in Plants, was so ploddingly empirical, describing the same experiments repeated over and over, that Darwin, characteristically candid, called it a “horrid bore” and encouraged readers to skip to the summary at the end. (Good advice, Thompson notes.) But Darwin’s volume on orchids—his first book after The Origin, a sly follow-up—explored a dazzling variety of adaptations by which orchidaceous plants get themselves fertilized by insects, and his book on carnivorous vegetation explained how and why some plants growing in nutrient-poor substrates meet their nutritional needs by catching and digesting animals. 

Those and the other plant books all retold the story: excess population, competition for resources, and random variation, with its attendant differential success in reproduction, constitute natural selection, yielding elaborate adaptations. Darwin’s famous prediction about the Madagascan orchid Angraecum sesquipedale, with its tubular nectar receptacle eleven inches deep, shows the interconnection most dramatically. He correctly deduced that a moth with an eleven-inch nectar-sucking proboscis must exist to pollinate it, because the plant’s manifest adaptations demand that. Forty years after Darwin’s orchid book appeared, the moth was found. 

Elizabeth Hennessy’s On the Backs of Tortoises is the best history of the Galápagos archipelago that I’ve ever read, but it’s also something more argumentative: a postmodern critique of certain prevailing myths about the Galápagos Islands and what Hennessy posits to be the guiding (but misguided) principles of conservation biology, as applied to those islands and elsewhere throughout the world. Her book reminds us that the Galápagos have a history of their own, much broader and more complicated than their five weeks as a layover for HMS Beagle and its gentleman naturalist. She argues that seeing this place as a proscenium for one curious Englishman, with his observations of certain creatures and his developing evolutionary thought, is not only reductive but oppressively wrong. She wants to get to the bottom of the geographical, biological, and political realities of the place and its people. 

But what’s at the bottom if Earth itself (according to myths in several cultures) is supported in space on the back of a giant turtle? Hennessy revives the familiar anecdote, “as likely legend as true,” of some august professor (William James, in her version) being challenged by an elderly woman after a lecture on theories of cosmology. The woman tells James that, as everyone knows, Earth rests on a huge turtle. But what’s under the turtle? he challenges. A bigger turtle, she answers. And beneath that? he asks. “The old woman smiled and shook her head, ‘Very clever, Mr. James, but it’s turtles all the way down!’” 

For Hennessy, it’s Foucauldian power dynamics all the way down: 

Galápagos conservation is a place-based endeavor in which evolutionary understandings of life—what species evolved over hundreds of thousands of years on which islands—inform a biopower that values and aims to “make live” certain endemic species, such as the giant tortoises. 

What she means by “make live” certain species, I think, might also be said as “privileging” them—over the claims of people and their cows, for instance. The word “biopower” is Foucault’s coinage; its rough sense is that modern Western societies have found ways of controlling some groups of humans (and maybe of nonhuman animals too) on grounds of mere biological realities. It’s a way of managing populations. Applied to conservationists and their efforts to preserve endemic species of tortoise and marine iguana and mockingbird and other fauna and flora unique to the Galápagos, sometimes at the cost of exterminating rats or feral goats or constraining commercial activities such as fishing or ranching by human settlers, the word “biopower” is not flattery. 

There’s some justice to everything Hennessy says about these power dynamics, and she presents a mountain of fine historical research to support her assertions. She takes us from the earliest known human landfall on the islands—by the Spanish bishop Fray Tomás de Berlanga, whose ship drifted off course on his way to Peru in 1535—through the years during which, with their springs of fresh water and their abundance of meaty tortoises, the Galápagos were convenient provisioning stops for buccaneers and whalers. The tortoise meat was highly prized and could be kept fresh for months in the form of live tortoises, helpless and doomed, stored upside down aboard a ship. 

After the whaling men and pirates, after Herman Melville (who called these islands the Encantadas, or enchanted, in his novella of that name), after a team from the California Academy of Sciences came specimen-collecting in 1905—killing wildlife like drunken sailors but with what they considered higher purposes—and then after another half-century of settlement by Ecuadoran mainlanders who wanted to mine guano, or farm, or fish, plus a few ditzy Europeans hoping to live out Swiss Family Robinson fantasies, came the era of conservation and more continuous scientific attention. That began formally with the establishment of Galápagos National Park by the Ecuadoran government in 1959 and the founding of the Charles Darwin Research Station on the island of Santa Cruz. The park, which became an international tourist attraction, encompasses 97 percent of the land area of the islands, leaving aside the 3 percent that had already been claimed by settlers, “as if a boundary fence might be capable of holding strong this divide,” Hennessy comments, “so that conservationists can save the tortoises—and tourists can photograph them too.” Meanwhile, the settlers, she implies, get the pauper’s share. 

Amid this sweep, Hennessy makes two points, not original but worth noting, about Darwin’s brief visit in 1835: he didn’t scruple to eat tortoise meat himself, and he didn’t conceive his dangerous idea during that stopover, either while gazing at finches and mockingbirds or while noticing different tortoise shapes on different islands. He only began to ponder species and varieties in a new way. He went home without a theory. The moral, for Hennessy, seems to be: If you think the Galápagos tortoises are so inviolable and precious, be aware that Darwin didn’t, and that the notion of his great epiphany having occurred here is a myth. 

By the early twentieth century, she writes, the sailors and settlers and hungry scientists had accounted for the deaths of some 200,000 giant tortoises, eliminating the populations on three islands and devastating the others. “The remaining tortoises are ‘living fossils,’” she asserts, “remnants of a prehistoric world when giant reptiles and other megafauna roamed the Earth.” This seems to imply that Galápagos tortoises date back to the time of the dinosaurs (which weren’t reptiles), an impression that’s wrong on several counts. Land tortoises of any sort first appeared about 10 million years after the last dinosaurs died, and those native to the Galápagos are probably much younger. Hennessy must know that, but she portrays them as very ancient, or perceived as very ancient by those who dote upon them, in order to argue that saving them is a dreamy act of nostalgia. 

The fulcrum of Hennessy’s quarrel with Galápagos conservation efforts is that their avowed purpose is to create an “evolutionary Eden,” a sort of “natural laboratory,” pristine and devoid of people, in which the tortoises can be bell-jarred as priceless biological antiques. She harps on the wrongness of the “evolutionary Eden” metaphor, noting that it’s not only a futile goal and unfair to the interests of humans on the islands (especially those engaged in any form of livelihood besides scientific research and tourism), but also contradictory, given that conservationists, in trying to preserve the place and its biota in some ideal, primordial form, are ignoring Darwin’s lessons that life is about evolution and evolution is about change. 

She notes rightly that conflicts about wildlife “are not just about wildlife.” They also involve “the validity of deep-seated questions about identity, belonging, and access to resources.” Again, true and important. But the “Edenic science” she criticizes is largely a straw man, supported in her book by some well-selected statements by Galápagos popularizers speaking loosely about “Eden” and a land “where time stood still”—statements that look silly nowadays but don’t define what’s at issue and are not, in my view, representative. 

Although Hennessy knocks the straw man over, she doesn’t prove the illegitimacy of conservation biology. Most people and organizations involved in it are not arguing for the preservation of some “evolutionary Eden.” They’re saying: Let’s protect biological diversity wherever possible, including on islands, where evolutionary change has produced unique creatures—creatures of the present, such as giant tortoises, giant prickly pear cacti, flightless cormorants, seagoing iguanas—that are precious beyond any practical measure. And biological diversity is not a subjective matter. It can be measured. It can even be counted. 

Bill Jenkins’s Evolution Before Darwin traces the development of ideas about evolution (or, as it was then called, transmutation or transformism) among certain scientists and teachers in Edinburgh during the first three decades of the nineteenth century. That’s an important place and period in scientific history, only partly because Darwin attended the University of Edinburgh as a medical student from 1825 to 1827 (he detested it, quit, then ended up at Cambridge doing more general studies, which didn’t involve dissecting corpses), and was exposed to some of those transformist thinkers. “Out of the ferment of ideas that were current in Edinburgh in the 1820s and 1830s,” Jenkins writes, “came the building blocks” of Darwin’s later evolutionary theory. But did the young Darwin acquire those blocks directly from teachers he met in Edinburgh—despite his later claim not to have—or did he mix, mold, and fire his own from raw materials found elsewhere? And if Edinburgh voices gave him his start in transformist thought, why did he choose to deny it afterward? 

Jenkins’s book on the evolutionary ferment in Edinburgh hangs implicitly on one teacher–student relationship: that between Charles Darwin, an impressionable seventeen-year-old, and Robert Grant, thirty-three, a lecturer on invertebrate animals at one of the private anatomy schools that functioned as supplements to the university’s medical program. Darwin probably met Grant through a natural history society of which both were members and became a sort of protégé to him in marine zoology (as Darwin himself described fifty years later in his autobiography). Grant was brilliant, mercurial, educated partly in Paris under the great anatomists Georges Cuvier and Étienne Geoffroy Saint-Hilaire, and radical both in his scientific and his religious views. He believed in transformism, though without a clear theory of how it worked, and among his main influences were the writings of Jean-Baptiste Lamarck, still alive then in Paris, and the eclectic English physician, poet, and philosopher Erasmus Darwin, Charles’s long-dead grandfather, who had published a book containing inchoate transformist speculation. 

Sometime during their shared days in Edinburgh, Grant vented to Darwin his enthusiasm for Lamarck’s ideas. Darwin recalled in his autobiography that he had “listened in silent astonishment, and as far as I can judge, without any effect on my mind.” Yes, the seed of Lamarckian transformism may have been tossed onto the moist soil of my teenage brain, Darwin was saying, but it never sprouted. Jenkins suggests that this was disingenuous, and that old Charles had reasons for harrumphing away what young Charles may have absorbed in Edinburgh. 

The central figure in Jenkins’s story is neither Darwin nor Grant but Robert Jameson, Regius Professor of Natural History at the university for half a century, one of the leading geologists in Britain, and editor of the Edinburgh New Philosophical Journal, which during the 1820s and 1830s published some daring articles with transformist insinuations by Grant, Robert Knox, Ami Boué, and other young men of their freethinking Edinburgh circle. Jameson came off poorly in Darwin’s later recollection as “that old, brown dry stick Jameson” whose lectures were “incredibly dull” and repelled him from geology (though at Cambridge, geology would become his first scientific love). 

Other testimony is kinder to Jameson, and Jenkins shows that he used his considerable influence “to promote the careers of some of the most radical thinkers of their generation,” including Grant and Knox. Like his friend Grant, Knox had studied in Paris under Geoffroy, becoming enamored of his “doctrines of transcendental anatomy and unity of plan,” as Jenkins calls them, which were one big step toward evolutionary thinking. Back in Edinburgh and running the private anatomy school where he and Grant taught, Knox was a colorful figure, blind in one eye, pockmarked, given to frilly clothes and jewelry, and by contemporary accounts a riveting lecturer. 

We can imagine it was a lively milieu, at least for those brief two decades, with the spirit of David Hume still alive in the city and the radical French ideas coming back across the Channel in the heads of young Scotsmen. Grant was the only one of them to publish overtly transformist papers under his own name in Jameson’s journal, but others (including probably Jameson himself) wrote anonymously about the progression of life forms presented in the fossil record, teasing at what that must mean. Jenkins concludes that a significant portion of the ideas about nature that “formed the underpinnings” of Darwin’s theory “were present in the Edinburgh of the late 1820s, being discussed and debated by his friends, teachers and fellow students.” 

If so, why did Darwin prefer to forget or deny it? Jenkins’s explanation is plausible: Darwin at middle age was very concerned to present himself as an inductive thinker in the spirit of Francis Bacon, whom he quoted in an epigram to On the Origin of Species, or of John Herschel, whose 1830 book on scientific method, A Preliminary Discourse on the Study of Natural Philosophy, had made a huge impression on him in his Cambridge days. When he published his own big book (The Origin) in 1859, after twenty-one years of secretly nurturing his theory and gathering data to support it, he knew that he would face a cyclone of criticism. Some of that reflected sheer religious defensiveness, and some came from the scientific community, challenging his credentials (he had virtually none; he was just a wealthy man, with no professorship anywhere, working out of his home study), his epistemological methods, and his conclusions. Was he just another dizzy theorist, spinning out wild notions without any grounding in fact? No, just the opposite, Darwin insisted. He had “worked on true Baconian principles, and without any theory collected facts on a wholesale scale.” That collecting had begun in January 1832 on St. Jago of the Cape Verde Islands, where the Beagle made its first landfall after leaving England, and continued throughout the voyage and afterward. The theory arose from the data gathered (in the Galápagos and from many other sources); the data-gathering was not, at least in the early phase, driven by the theory. 

That was his story, largely true but of course oversimplified. And there was no place in it for the sort of wild speculations that had buzzed around his head in Edinburgh. Darwin was always a brilliant plodder, moving through intellectual terrain like a giant tortoise on the run, and that’s how he desired to be seen. 

He never liked public argument or disputation. Stressful interactions with other people made him literally sick to his stomach, part of a mysterious pattern of physical ailment that affected him intermittently throughout much of his adult life. He vomited often. He took quackish water cures. And then, after The Origin appeared, after the controversy it provoked, after Thomas Huxley and others defended him like paladins for a reclusive prince, after he published The Descent of Man, and Selection in Relation to Sex in 1871, taking his theory of evolution one step closer to the touchy matter of human origins, and after that book was fiercely attacked, he seems to have felt a bit beaten up. His old colleague Wallace, with whom codiscovery of the evolution theory had led to friendship, wrote him that summer, “I am very sorry you are so unwell, & that you allow criticisms to worry you so.” Darwin had slightly more than a decade to live. 

But there were more books in him, and they were mainly about plants. He had already published the orchid book and another about climbing plants. Now he shifted entirely to botanical projects for a stretch of five years, as recounted by Thompson: insectivorous plants, the effects of self-fertilization versus cross-fertilization, the different forms of flowers that can appear on plants of the same species—some intriguing topics and some numbingly dull ones. How many readers could get excited by the fact that a single primrose plant can produce two kinds of flowers, virtually identical but one with a long style (the stalk that channels pollen tubes to the ovary) and one with a short style? How many critics would be incited to contest hotly the explanation for such a phenomenon? The answer is essentially none, and I suspect that’s a clue to understanding Darwin’s final years. I’ve long cherished a pet theory that he turned to these arcane botanical studies—producing more than one book that was solidly empirical, discreetly evolutionary, yet a “horrid bore”—at least partly so that the clamorous controversialists, fighting about apes and angels and souls, would leave him the hell alone. 

By the time he died, painfully but with quiet dignity, of heart disease on April 19, 1882, he had lived seventy-three years and written more than a dozen books. Some of those books are easily ignored or forgotten. Some (the Beagle journal, the little volume on earthworms and their role in creating soil) are fun and charming. Some grind along through important stuff. One of them flows briskly and changed the world. Sadly, not enough people read On the Origin of Species today—even graduate students in evolutionary biology don’t all read it—but no one escapes its meaning and its implications. It was a brilliant start toward understanding how life works, how the wonders of diversity and complexity and adaptation have come to be, and we’ll need plenty more good books before we fully comprehend where it leads. 

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