Magpie - Reef Madness: Charles Darwin, Alexander Agassiz, and the Meaning of Coral - David Dobbs

Reef Madness: Charles Darwin, Alexander Agassiz, and the Meaning of Coral - David Dobbs (2005)

Part I

Chapter 1. Magpie

1

THE NAME AGASSIZ, from the southern, Francophone area of what is now Switzerland, means magpie-a bird, of course, but also a person, as Webster’s puts it, “who chatters noisily.” If this did not hang well on the reserved man that Alexander Agassiz would become, it fit his father snug. Louis Agassiz talked as voluminously and engagingly as anyone ever has about science, or for that matter about almost anything. He could mesmerize a room full of scientists, an auditorium flush with factory workers, or a parlor pack of literati, including his salon companions Oliver Wendell Holmes, Ralph Waldo Emerson, and Henry Wadsworth Longfellow, the sharpest talkers in a smart and garrulous town. He was one of those brilliant, ablative sorts whose immense skill in their main work is nearly eclipsed by their gift for talk.

Theorative urge can serve teachers well, scientists poorly. Yet if it distracted him from work, Louis’s eloquence accounted for much of his renown, throwing a glow around his theories and accomplishments that made them appear more illuminating than they were. His reputation grew much larger than justified by a sober look at his work. In Louis’s American prime, from the mid-i840s to the late 1850s, the clerisy considered him the country’s supreme scientist and one of its greatest intellectual talents. The public granted him that status even longer, well beyond his death in 1873. When he passed away, the major newspapers carried the news in huge type on their front pages, as if a president had died, and the nation’s vice president attended the funeral. The country’s top literary figures wrote aggrieved elegies; Oliver Wendell Holmes composed one for the Atlantic Monthly, a sort of house organ for Louis, adding to the several Agassiz odes he had already printed there. Even today, though time and Louis’s lost battle against Darwin have diminished his reputation, he stands as one of the giants of American science. Of scientists (rather than inventors) working in America, only Albert Einstein ever gained a similar combination of professional respect and public adoration. Yet Louis Agas-siz’s work never remotely approached the originality, importance, or practical implications of Einstein’s. With one exception, his ice age theory, the main theories he promoted fell obsolete, at least among scientists, even before he died. Yet he still stands as a scientific icon.

Louis Agassiz in 1844, during a time when he felt he would realize his ambition and become the world’s greatest naturalist

His fame comes in part from his establishment of the Harvard Museum of Comparative Zoology, a highly productive institution that trained many good scientists and, through example, competition, and direct mentorship, helped spur the development of other leading institutions. This and his ice age work would rightly place Louis Agassiz among the significant figures of American science. But those accomplishments don’t explain his exalted status.

How did a man who made few enduring original scientific contributions become a lasting symbol of American science? As his early biographer, Jules Marcou, a French protégé who followed Louis across the Atlantic to work with him for several decades at Harvard, noted, “He was one of those very few men whose works are not sufficient to make him entirely known; one must meet him face to face… Agassiz himself was more interesting than his works.” This can read as both praise and damnation, of course, reflecting the ambivalent tone of Marcou’s biography. (Marcou’s book, published after Louis had died, would enrage Alexander, who tried to have its more critical and personal passages suppressed.) But Marcou knew Louis well. He recognized in him that intangible quality that enables some people to move others to adoration, action, and a permanent change in thinking. Louis Agassiz thrillingly personified a Romantic ideal that combined deep learnedness with avid curiosity-and flattered his followers by emphasizing the latter. Though his own best work rested as much on reading as on observation, he urged his students to “study nature, not books.” It was a delicious invitation to a young country in a Romantic era. With his childlike enthusiasm, acute eye, mongoose-quick mind, and charming mispronunciations, Louis sold beautifully the primacy of clear-eyed observation over bookish learning. To an audience eager to claim its own intellectual legitimacy he insisted that vigorous, hands-on study of nature would not only strengthen mind, body, and soul but yield a knowledge greater than any library could hold. It was as if Louis’s mentor Georges Cuvier, the learned taxonomist and brilliant lecturer of early-nineteenth-century European science, had fused with Walt Whitman and Teddy Roosevelt.

Was ever another like him? His son, Alex, must have asked him self that, as virtually everyone who knew Louis did at some point. The obvious answer was no. He threw a hell of a shadow.

2

When he was twenty-one, Louis Agassiz wrote his father, “I wish it may be said of Louis Agassiz that he was the first naturalist of his time. … I feel within myself the strength of a whole generation to work toward this end, and I will reach it if the means are not wanting.”

Even for someone just past twenty, this ambition, particularly its sense of possessing the power of an entire age, is stunning in its confidence, scope, and focus. Yet young Louis had good reason to feel so strong. He was an accomplished, determined, and stupendously energetic prodigy. The son of a pastor, raised near the Jura Mountains in southwestern Switzerland (then a loose collection of cantons under Prussian rule), Louis showed from his earliest days a precocious brilliance. As a boy he spent countless hours hunting, fishing, and gathering bugs, small mammals, and fish, keeping many of the survivors in cages and aquaria at home. (Magpie also denotes an obsessive collector.) When he was fifteen, he composed a ten-year plan for himself requiring rigorous collecting and dissection of specimens; wide reading in science, literature, and philosophy; and eventual study at leading natural history institutions in Germany and then Paris before launching his career as a naturalist at twenty-five. He would follow this program with remarkable faith. During his adolescence (which he spent mainly at a boarding school twenty miles from home), he not only carefully classified his finds but studied the logic behind the different classification systems then in use-a concern, as we’ll see, central to nineteenth-century zoological studies in general and to Louis’s career in particular.

He was prodigious in talk as well. At boarding school he attracted a circle of fellow bright gabbers, and by the time he entered university at fifteen, he hosted a student salon, known as the Little Academy, which convened in his rooms several evenings a week to discuss science, art, and culture. “Agassiz knew everything,” recalled a fellow Little Academician. “He was always ready to demonstrate and speak on any subject. If it was a subject he was not familiar with, he would study and rapidly master it; and on the next occasion he would speak in such brilliant terms and with such profound erudition that he was a constant sourse of wonder to us.

When his salon mates went home, Louis would resume studying, then go to bed late. The next day he would rise at six, spend most of the morning working in the lab, fence (at which he excelled), eat lunch, take a walk, study until dinner, and then reconvene his Little Academy and talk till the wee hours. He seemed never to tire (Alex and his friends would later call him “the steam engine”), and he appeared to retain all he heard, read, or saw. Once, asked to identify a fish, he recalled by drawer number a similar specimen he had seen more than a decade before at a natural history museum in Vienna. A subsequent letter verified both the identification and the drawer number.

He possessed a brash confidence that he could generally back up. According to one story (of many he would spawn), Louis, affronted by some perceived slight given his Swiss fencing team by a German team while he was studying in Munich, challenged the German team to a match in which he alone would take on the entire squad, one at a time. The Germans laughingly agreed. Louis dispatched first their best fencer and then their next-best three before the Germans threw in the towel.

He carried this competitive exuberance to friendships. He and his close friend Alexander Braun (who would become both a prominent botanist and Louis’s brother-in-law) once became so caught up in a conversation about fencing that they took up rapiers and sparred without thinking to put on their masks. They did not stop until Louis, the quicker of the two, had slashed his friend’s face.

He pursued education and career with similar zeal. His self-designed program ran into trouble early in his college years, when his parents made it clear they expected him to be a physician. He solved the problem (and retained his family’s financial support) by executing both his own and his parents’ plans, earning a medical degree even as he followed his own agenda by studying natural history in Luanne, Zurich, Heidelberg, Vienna, and Munich. He took both degrees in early 1830, at the age of twenty-two. Then he returned home for a few months to finish his first book, a catalog of fish, and planned the next stage of his campaign: Paris.

Louis’s ambitions had included Paris from the beginning, for Paris was then Europe’s most important centre of natural history study, outranking both London and Munich. At its heart was the Museum d’Histoire Naturelle, the largest and most prestigious institution in natural science, where Jean-Baptiste Lamarck and Georges Cuvier headed an illustrious and rivalrous staff. Their primary preoccupation was identifying, dissecting, and cataloging the many bio logical specimens of living and extinct species being sent to the museum from around the world. This discipline of classification, also known as taxonomy, had been essentially founded a century before, when the Swede Carolus Linnaeus roughed out the classification hierarchy of kingdom, class, order, genus, and species (phylum and family were added later) that has served so well and flexibly ever since. Linnaeus also invented binomial nomenclature, by which each species is known by its genus and species names (Homo sapiens, Falcoperegrinus).

Linnaeus’s system furnished a treelike organization in which to place new species. But it did not settle how many branches that tree should have at each level or how to decide on which branch a new species should reside. Those questions remained open, and the many scientific expeditions sent around the globe in the eighteenth and early nineteenth centuries had quickened the debate on how to answer them. Explorers were discovering species at an unprecedented rate, and the emerging science of paleontology was complicating things further. You had to figure out where to place not just an iguana but an iguanodon, a pterodactyl, and a platypus. You had to define categories broad enough to accommodate these species but narrow enough to be meaningful. What physical differences should divide categories at the most basic levels? How heavily should structural considerations weigh versus physiological? Was a crab, for instance, more like a spider or a starfish? A starfish more like a crab or an anemone?

Underlying these questions, and giving taxonomy the air of grand endeavor, was the sense that the discipline was not merely distinguishing among creatures but limning the order of God’s work. Taxonomy rose mainly from the practical need to identify all the species being discovered. But its emergence offered a great theological and political convenience, for it came at a time when those in Western science-funded and conducted largely by institutions and people who were either pious or under pressure to seem so-were glad to find a way to reinforce Judeo-Christian tenets. Discoveries about the earths age, like Copernicus’s and Galileo’s work two centuries before regarding our place in the universe, had forced a looser, more metaphorical interpretation of the Bible’s account of creation, making science once again seem a doubter of religion. Geological findings made it clear the earth was older than the Bible said it was, and the fossil record seemed to contradict the story of Noah’s flood. Although these discoveries didn’t turn Christian dogma upside down the way Copernicus’s work did and Darwin’s would, they forced a reworking of the biblical version of creation, a process that discomfited many and threatened some.

By placing all life into a systematic structure, however, taxonomy could glorify God by showing the order of his work. The binomial system did this beautifully, for its bifurcating-branch system graphically brought all life-forms back to the same tree trunk. This organizational scheme need not be theistic, of course; the same taxo-nomic system later readily described a nature created by evolution. But the tree of life described by Linnaean taxonomy could be easily offered and accepted as the work of God. Who or what else could create an array so marvelously complex and interconnected? Taxonomy allowed naturalists to elaborate rather than undermine the notion of a world made by a single, omnipotent Creator.

All this, along with the many new species being discovered, made taxonomy one of the most exciting disciplines in all of science. And Paris was the center of the taxonomic world, with Cuvier, Lamarck, Etienne Geoffroy Saint-Hilaire, and other taxonomists competing ferociously to parse God’s order. Cuvier had claimed the greatest renown among them through a combination of strong science, shrewd politicking, and bold showmanship. He had fundamentally transformed taxonomy by rejecting the notion of an animal kingdom that merely ranged from the simple to the complex and dividing it instead into four broad categories that he called “embranchments”: vertebrates, radiates, mollusks, and articulates. These same categories, which today we know as phyla, have (with about thirty additional phyla discovered since Cuvier’s time) headed the animal-kingdom framework ever since. This innovation created a far more logical and useful classification of the animal kingdom. In addition, Cuvier’s 1812 Recherches sur les ossements fossiles des quadrupèdes pioneered the science of paleontology and the classification of fossils. Cuvier even claimed to have developed a system, which he called the “correlation of parts,” for extrapolating an animal’s entire anatomy from almost any bone. Presented with just one bone from a newly discovered skeleton, he would wow audiences by predicting the structure of the remainder. He once did this with a fossilized opossum embedded in rock, successfully predicting, from what he could see of a tiny portion of the skeleton, that it would be an animal of the marsupial family.

Early in his career, Cuvier invented the term “balance of nature,” a coinage reflecting his belief that every piece of nature had a trace able link to every other. “Nature makes no jumps,” he wrote in one of his early papers, a 1790 Journal d’Histoire naturelle article about wood lice. He was essentially quoting Aristotle, but the idea served his purposes well. A wood louse was related to a snail and a whale, and if you worked long enough, you could trace the links.

This connected-web idea rose from Cuvier’s flirtation with the concept of a “chain of being” that connected all entities-animal, mineral, vegetable-in a single, unbroken sequence of related forms. This idea was central to the Romantic school of philosophy and science known as Naturphilosophie. Cuvier signed on to the chain-of-being idea for a time, then distanced himself from it because it played into the hands of pre-Darwin evolutionists, including his col leagues and rivals Lamarck and Geoffroy and because he felt growing unease with anything that seemed conjectural. Soon after dropping the chain-of-being idea, in fact, he forswore any notion that seemed speculative or even explicitly theoretical. Instead he put his faith in a presumably clear-eyed empiricism, in what could be actually seen or otherwise observed. From then on he would sub scribe to facts alone, recognizing only what order he could discern from ostensibly disinterested, assumption-free observation and description. “We know how to limit ourselves to describing,” he said, ignoring that in categorizing species he was imposing distinct ideas about how the world was organized. His supposed humility-his assertion that humans should not offer ideas about how God worked but should merely describe that work-hid the arrogance of his presumption that he could discern that work’s precise nature. He would have said the definition of a given species or other taxonomic category was not his idea but God’s; he just happened to be able to see it.

He had little doubt that he could see this order far better than could anyone else. He argued ferociously with Lamarck and others about how to divide the animal kingdom, usually prevailing (even though he was actually the weaker taxonomist in areas outside his beloved fish) because of his extensive publications and, more important, because his system of embranchments (or phyla) and his insistence on identifying specimens through dissection rather than external features were such useful tools for organizing the animal world. His taxonomic theory flourished and survived, of course, the same way a successful species does, through adaptability. Yet in Cuvier’s eyes his theory of biological organization, particularly the identification of embranchments, rose not from an idea but as the simple product of accurate observation: He did not invent the branches of the animal kingdom; he merely recognized them. Tax onomy-the description of the categories as well as the placement of species within them-was strictly empirical. The good scientist was content to see what things were, not to pose ideas about how they worked. Never mind that the notion of empirical truth was a pretty audacious idea itself.

3

Cuvier’s ambitious taxonomy, his certitude regarding his work and its significance, and his pinnacled status all appealed immensely to Louis. His example must have seemed replicable, for he was very much like Louis: the impeccable memory, the sharp eye and quick mind, the boundless ambition, the flair for the dramatic. They even shared the same taxonomic passion, cataloging fish.

Louis had decided early on that Cuvier was the only biologist who could complete his education. While still in Munich, Louis had begun cataloging a collection of fishes that one of his professors had brought back from Brazil, and he corresponded with Cuvier about them, seeking and getting guidance. Cuvier, as Louis well knew, was then cataloging all the known fish on the planet. He was glad to make Louis’s acquaintance. Louis worked hard on the book and did a solid job. When he finished it he sent Cuvier a copy with a humble note- and the book’s dedication page devoted to the master. Cuvier sucked in the bait. When Louis later wrote to say he wanted to come to Paris and to catalog the fossil fish of central Europe, Cuvier invited him to visit. Louis was quite excited. He saw the invitation as the beginning of something grand. Then, shortly before arriving, Louis heard that Cuvier had recently started work on some piscine paleontology of his own, cataloging all the fossil fishes of the world. (Like Louis, Cuvier rarely planned small.) Louis began worrying that his own work might be overrun by Cuvier’s, and when Cuvier received him politely but guardedly, not as an equal, Louis was at first disappointed.

Still, Cuvier was receptive enough, giving Louis lab space and access to some of the Muséum d’Histoire Naturelle’s samples. Louis, determined to make the best of it, put in fifteen-hour days, quitting only when the light failed. He worked so hard that he regularly dreamed about fossil fish. In one case he dreamed three nights running of a fish that he was trying to extract from its encasing stone. On the third night, seeing its full form, he awoke and drew it. When he finished extracting the fish that day at the lab, he found it looked exactly as in his sketch. He had in his sleep performed a Cuvierian correlation of parts.

Cuvier, perceiving in Agassiz a rare acuity and power, soon granted him complete access to the museum’s fossil collections and asked other Paris curators to do the same. He began inviting Louis to his home for Saturday-night salons, then weekday dinners. He showed him the ropes of professional Paris, encouraged and praised him, even recommended him and his coming fossil fish monograph to the Académie des Sciences, a virtual guarantee of prominent publication. Most significant, Cuvier passed to him his project cataloging all known fossil fishes-and not, as Louis had feared, in the role of under ling coauthor but as lead researcher and author. Cuvier too gained from this gift, for with much of a museum to run, other taxonomy and paleontology work waiting, and a project under way to describe the geology around Paris, he was badly overextended. Nonetheless, the gesture carried incalculable value. It erased the potential conflict between Louis’s European project and Cuvier’s global project, so Louis would not have to choose between subjugating his work to the master’s or offending him (and risking obscurity) by offering a competing work. And it represented a show of faith and even affection, for fossil fish were among the subjects closest to Cuvier’s heart.

Cuvier took on many protégés, for he always had more projects than he could handle. (Louis would later imitate him in this as in many things.) But the fossil fish project, along with all the time the two spent together, made it clear that Louis Agassiz was Cuvier’s brightest young star, the golden boy who matched the master’s powers. It seemed almost as if Cuvier was preparing him as successor. He introduced him to Paris’s scientific and cultural elite, taught him tax onomy, showed him how to manage a large museum and, by example, how to cultivate and wield influence and authority.

One such demonstration, a formative experience for Louis, was a debate that Cuvier was conducting with Etienne Geoffroy Saint-Hilaire, the museum’s professor of vertebrate zoology and another leading taxonomist, over the nature and relationships of the animal kingdom’s organization. While Cuvier divided the animal kingdom into different embranchments distinguished by mutually exclusive “ground types,” Geoffroy insisted that all animals were variations on one essential form. This idea had philosophical underpinnings in the chain-of-being theory, which, ironically, Geoffroy had learned first from Cuvier, and, more deeply, from Naturphilosophie, which held that all life-forms were variations on a few essential archetypes. Geoffroy, as his late colleague and mentor Lamarck had before him, now explained those variations as the results of some sort of evolutionary force that moved them away from the original archetype and argued that their common heritage gave them a “unity of composition” (that is, fundamental likenesses).

It was a nice tautology, completely untestable, and exactly the sort of speculation Cuvier despised. The notion of evolving species also clashed with Cuvier’s creationist conviction that the earth’s creatures were God’s work. Geoffroy and Cuvier debated the issue tirelessly. By the time Agassiz witnessed their final rounds, they had been hammering at each other for a quarter century. Twenty-five years before, in 1807, Geoffroy had seemed to disprove Cuvier by showing an essential skeletal similarity between the forelimbs of terrestrial vertebrates and the pectoral fins of fish. Cuvier countered by finding in fish the apparently unique structure of the operculum, a bony flap covering the gills. This set Geoffroy back a spell. But after consider able work (ten years of comparative anatomy) he was able to draw a plausible connection between this supposedly unique operculum and several mammalian auditory bones, thus reasserting unity of composition. Along the way, the two managed to embarrass each other many times. Geoffroy, for instance, once caught Cuvier mis- classifying a certain reptile fossil as a close crocodile relative, while Cuvier had great fun ridiculing Geoffroy’s assertion that anemones and mollusks rose from the same basic form as vertebrates.

The two were now trading jabs through alternating lectures at the Académie des Sciences and the Collège de France. In the face of Cuvier’s repeated attacks on the speculative nature of his arguments, Geoffroy seemed to be losing the larger arguments about both tax onomy and evolution, and for good reason. Cuvier’s notion of embranchments simply seemed to make more sense, particularly in its division of vertebrates from other animals. Anemones and centipedes, after all, strike anyone as different from squirrels and birds. And while evolutionary theory would eventually displace Cuvier’s notion of fixed species, Geoffroy, like all pre-Darwinian evolutionists, could offer no plausible explanation of how evolution occurred. He could only point to results. He had a body-piles of bodies-but no smoking gun. He failed to make a solid case for evolution because he could not identify a process by which it worked. With no dynamic to point to, he lost to the prevailing explanation: Animals were the way they were-variations, similarities, and all-because God made them that way. So Cuvier won, at least for a time.

For Agassiz, who had found the chain-of-being idea attractive while in Munich (his friend Alexander Braun would sign on permanently), the Cuvier-Geoffroy feud revealed how readily an empirically based argument could triumph over abstract theory. This did not mean that empirical arguments lacked grand meaning, at least in taxonomy, for there was significance aplenty in delineating God’s order. Rather it meant that any claim to a large idea, such as the existence of embranchments, should rest on a wealth of tangible, observed evidence showing the idea’s close, demonstrable correspondence to physical reality. If it did, it would beat speculation about hidden dynamics every time.

4

Cuvier’s example confirmed most of Louis’s prejudices and ambitions. The rewards of being “first naturalist” seemed great indeed. Cuvier, a baron by now, enjoyed numerous commissions, titles, and positions, abundant income, and enormous influence. He consumed heartily (his nickname, “the Mammoth,” referred to more than just paleontological interest) and had the world at his feet. Temperamental and impatient, he was said to hold an enlightened despotism as his own political ideal. Yet he knew when to take a knee. When Napoleon rose to power in 1804, Cuvier seamlessly transferred his allegiance to this new ruler, tempering certain religious views accordingly. He did the same when the monarchy replaced Napoléon in 1814 and then a third time when the 1830 revolution deposed the crown. “What servility and baseness has not been shown toward those in power by M. Cuvier!” wrote Stendhal. But it worked. Over the first three decades of the 1800s, no scientist lived better or wielded more clout. He not only stood atop the scientific establishment but held an influential position as a councillor of state (a combination advisor and judge) in France’s administrative judicial system. Cuvier loved it. He exercised his authority with a largesse and ruthlessness that reflected back to him, in both the gratitude of those he helped and the pain of those he hurt, the scope of his own power.

Louis seemed to absorb, as a healthy thing, Cuvier’s entire example. Holding his own in conversation with the city’s most prominent scientists and citizens, eating beyond his means, standing alongside Cuvier at the pinnacle of Paris’s social and scientific worlds, he enjoyed the heady feel of extreme prominence. Here was a model to emulate: an intellectual stance that combined painstaking rigor with a view of the big picture, and a position of power and influence that provided the space, money, materials, and assistance his ambitions demanded.

He was still soaking it up when Cuvier suddenly died of cholera in May 1832. Louis had known him just six months. The relationship ended when it was at its most exciting, expansive, infatuated stage. But rather than fall to earth, Louis would self-consciously continue along that exhilarating arc of encouragement and possibility. Cuvier had confirmed Louis’s opinion of himself as his generation’s greatest talent, and Louis saw no need to seek a second opinion. While he accepted the friendship and guidance of Alexander von Humboldt for a few months after Cuvier’s death, he would never meet another scientist he considered his superior. The torch had been passed. Louis, feeling born to the job, gladly took it in hand.