Carl Linnaeus (Andrew Berry)

From the Quicksilver Metaweb.

Carl Linnaeus (1707-1778) is famed both as a botanist and as the founder of the modern system of biological classification. Although he initially focused on plants, he subsequently expanded his taxonomic ambitions to include all of the natural world, and duly set about classifying animals. He was rather better, it turned out, at organizing the plant kingdom than the animal one: for example, most invertebrates were cheerfully lumped into the catch-all grouping “vermes.” And he mistakenly classified hard-shelled invertebrates twice, as testacea (on the basis of their shell) and as mollusca (on the basis of the soft-bodied animal within). Perhaps, given these zoological shortcomings and his affinity for plants, we shouldn’t be surprised that Linnaeus himself was named for a tree. In “Linnaeus: Nature & Nation,” Lisbet Koerner takes up the story:

Linnaeus’ father, Nils Ingemarsson, had named himself Linnaeus to celebrate a triple-trunked linden tree growing next to the family farm in Småland, Sweden. So magnificent was the tree that two of his maternal uncles also gave themselves family names in its honor. According to local tradition, it was a magic growth, and its well-being was linked to that of the families that farmed its land.

Linnaeus’ years as a sapling were undistinguished. He was an unremarkable student in school, and his teachers had no difficulty convincing him that he was not cut out intellectually for the career his father, himself a clergyman, had chosen for him, the church. Instead, Linnaeus opted for medicine. First at Lund and then at Uppsala universities, he followed up on the interest—botany—he had first developed as a child in his father’s garden. The medical faculties at both universities were in decline and quality educational opportunities were in short supply. Botany, however, was a major component of the medicine of the day: that era’s version of prescription drugs consisted of the medicinal plants collected and prepared by a doctor. At both institutions, Linnaeus made the most of what would become an important lifelong ability to impress influential (and often wealthy) patrons. As an impoverished student from the provinces, times were hard for the young Linnaeus, but distinguished professors, apparently seeing potential in his hard work and passion for plants, took him up their wing. Formal education he may have been lacking, but he nevertheless benefited from direct access to some of Sweden’s leading scientists.

Inspired by one of these professors, Linnaeus won a grant from the Uppsala Science Society for an expedition to Lapland. He traveled extensively, making significant botanical collections and contributing to the enthnographic literature on the indigenous Sami. It was largely on this experience that Linnaeus’ claim to being an explorer rested. Unfortunately, like plenty before him, and plenty after him, he was keen after the event to make the undertaking appear more heroic than it really was:

No high-altitude plants are described in Flora Lapponica or found in Linnaeus’ extant herbaria. Yet in Flora Lapponica Linnaeus made much of how in Lapland he climbed “the sky-high mountain overhangs, the terrifying rocks, the threatening boulders, the precipitous stone slabs.” He clearly kept to the valleys. But his travel report to the Uppsala Science Society describes how he fumbled about, blinded by fogs, on the cloud-covered rock faces of what he argued were Europe’s highest mountains. Flora Lapponica’s frontispiece, the design of which Linnaeus oversaw, piles up jagged alpine peaks—far removed from Lapland’s pudgy, worn-down hills. [Koerner]

On a later journey to central Sweden, he met and became engaged to Sara Lisa Moraea. Their getting married, however, depended on his completing his studies so that he could enter the medical profession. Botany would—briefly, at least—have to take a backseat. In 1735, he duly set off to the Dutch university of Harderwijk which was the closest that mid 18th century Europe had to a mail order university. He spent all of eight days there, submitted a feeble 13 page thesis on how malaria (then a major disease in Europe, including Sweden) was caused by the presence of clay in drinking water, and received his medical degree. Sara Lisa, however, would have to wait. Again putting to good use his ability to induce the great men of the day to sponsor him, he spent the next three years in Europe visiting and learning from leading botanists. It was at the beginning of this period, in 1735, that he first published the outline of his ideas on biological classification in Systema Naturae. In this first edition, it weighed in at eleven succinct pages. By its twelfth edition, published 1766-68, it had expanded to 2,300 pages.

There are two major elements to Linnaeus’ system: the hierarchical organization and the use of binomial nomenclature. Species are designated with two names, such as Homo sapiens, where the first refers to the genus (which normally contains multiple species) and the second to the species itself. Linnaeus was the first to be utterly systematic in the use of a binomial system but he certainly was not the first to introduce such a system. In colloquial English, for example, we refer to barn owls and snowy owls, recognizing in effect that both species belong to the same overall group, owls, but are nevertheless distinct. Linnaeus’ hierarchy went, from bottom up, species - genus - family - order - class. The highest level of the hierarchy, phylum, was introduced later by the French naturalist, Georges Cuvier (1769-1832). We now understand that the hierarchy systematized by Linnaeus is the product of an evolutionary process. Species that share a relatively recent common ancestor are similar and are placed in the same genus; species that share a more ancient common ancestor are less similar and may belong to the same family, but not the same genus. Linnaeus basically provided a way of organizing the species in the evolutionary tree of life.

How was Linnaeus able to do this more than 100 years before Charles Darwin published The Origin of Species? We now understand that the hierarchy that is discernible among species is the product of the evolutionary process; in pre-Darwinian times that hierarchy was just as readily identifiable—it was in the matter of cause that pre-Darwinians differed from Darwinians. The hierarchy, so far as Linnaeus and others of his generation were concerned, reflected God’s preferred method of design. Whereas we appreciate that the fundamental similarities between the barn owl and snowy owl stem from their having a relatively recent common ancestor, perhaps the first owl, Linnaeus assumed that God had hit upon a general plan for the owl, and then gone to work to produce variations on the basic concept, each one well fitted to its environment. Thus, surprisingly given the utterly opposed motivations of the two approaches—one materialistic, the other divine—both pre- and post-Darwinian taxonomy yielded the same basic results.

Linnaeus subscribed to the day’s Natural Theology, which argued that creation was both a reflection of God’s mind, and the gift of God to his proudest creation, humans. One of Linnaeus’ students captured these sentiments when writing to his professor in the course of a collecting expedition to South America: “I now am allowed to wander in Surinam, an earthly paradise, and see the great god’s greatest miracles in nature.” (Not, sadly, for long. The student was soon to become mentally unhinged in his tropical isolation, eventually returning to Sweden to eke out a living as a beggar). Linnaeus accordingly regularly attended church, and certainly never embraced the atheistic views of some his more sophisticated contemporaries. Linnaeus’ one complaint with organized religion was that sermons could go on for too long. He trained his dog to slip out of the church during particularly long ones, and then would himself have to depart on the pretext of hunting up the missing animal.

Linnaeus’ biological insight extended beyond merely organizing nature. For instance, he was the first to recognize that the rings apparent in the cross section of a tree trunk are a documentary record of the tree’s year-to-year, season-to-season growth, and he is thus the father of the science of dendrochronology. His deep knowledge of the natural world meant that he was one of the first ecologists (a long time before the discipline even had a name), and his descriptions of the inter-dependence of species impressed even Darwin. As we shall see, Linnaeus was forever keen to apply his biological knowledge to practical problems, and he was therefore one of the first proponents of what today we call biological control, the regulation of pest species using their natural enemies: “Until now no one has thought about exterminating insects with insects. Most every insect has its lion with persecutes and exterminates it; these predatory insects ought to be tamed and taken care of, so they can purge plants.”

In 1738, now a man of the world, Linnaeus returned to Sweden and married the patient Sara Lisa. He set up as a doctor in Stockholm—his specialty was venereal diseases, and among them syphilis his forte—where he also lectured on botanical subjects at the university. In 1741, he was appointed professor of medicine—read, botany—at his alma mater, Uppsala, and here he set about consolidating his scientific work, and inspiring a generation of students. Many of these went on to successful careers of their own, and several were notable scientific explorers in an era when Europeans were ranging far and wide in pursuit of empire and trade. Daniel Solander, a Linnaeus student, accompanied Captain Cook on his first voyage (1768-71). It was the discoveries made on these journeys that inspired the second phase of Linnaeus’ career: the earth was clearly a treasure house of natural wonders ripe for exploitation by humans, and Linnaeus was determined that Sweden should be a major beneficiary.

In particular, he aimed to grow exotic crops—rice, tea, and plenty more—in the Baltic region. In addition, he sought in the native Swedish flora plants that would substitute for crops, like coffee, that even Linnaeus admitted would never grow in Sweden’s boreal climate. Sweden, in Linnaeus’ vision, would become self-sufficient. Famine—a frequent event in Sweden in Linnaeus’ time—would be a thing of the past. Koerner describes his motivation:

They may seem odd to us: our hero’s scramble to grow rice in Finland or tea in Lapland. Yet Linnaeus’ notion of floral acclimatization and his seach for indigenous flora underwrote his most basic political goal: to reproduce the economy of empire and colony within his Baltic country, and thus to short circuit the economic improvements achieved by Holland and England through their international trade. When Linnaeus predicted that Scandinavia’s tundra—with its shallow summer melts overlying permafrosts, its glaciers and fields of lichen-covered boulders, its sparse migratory animals and vast seasonal swarms of insects—would flourish with tea plantations, saffron meadows, and cedar forests, all tended by nomads turned farm laborers, he envisioned a future world profoundly different from the one that came about.

It seems that Linnaeus’ vision of a self-sufficient Sweden over-ruled his years of hard-won biological knowledge. He, of all people, was well placed to understand how plants are adapted to their environments, of which climate is an important component. And yet—as an eerie precursor to the great failed Soviet agricultural experiment led by Trofim Lysenko in the middle of the 20th century—he believed that it would be possible to “acclimatize” plants from warm climates to the harsh winters of Sweden. His scheme was a gradual one, with plants being moved progressively north. Tea was a special interest and the saga of his attempts first simply to acquire viable tea plants (transport from the East to Sweden was a major problem, especially as sea routes inevitably came through the stifling tropics) and then to cultivate them is especially pathetic. Linnaeus did not limit his importation suggestions to plants. For a meat supplement, he promoted guinea pigs, “slaughtered, shaved, and fried.”

Curiously he was unaccountably resistant to some of the established success stories in plant importation. Potatoes, for example, are well adapted to the growing conditions of Sweden, and, in nutritional terms, have a high yield, but Linnaeus was unimpressed, insisting that, as members of the same plant family as deadly nightshade, they were poisonous. He even produced “experimental” evidence to make his point: “We had a whole heap of swine herded into the courtyard, and in front of them was thrown a sizeable heap of potato roots [ie potatoes]… but the naughty swine didn’t voluntarily eat a single one but ferreted out bread and other bait, that had been thrown in among the roots.”

His suggestions for expanding the range of plants used by Swedes seem to us—and I suspect to the Swedish peasants for whom the advice was intended—unappetizing. Coffee could be substituted with a brew made from burnt “peas, beechnuts, almonds, beans, maize, wheat, or toasted bread.” And starvation would surely be eliminated if only people would learn to eat local fare like fir bark, nettles, acorns, Iceland moss, seaweed, burdock, polypody, bog myrtle and thistles.

Linnaeus’ food crusade was bound to fail. His concerns for the people of Sweden were heartfelt—colleagues were always surprised when the great man stopped, as he always did, to give to beggars—but this is a clear case of political desire elbowing aside scientific wisdom in the scramble to contribute to society.

As he became more famous and an ever more entrenched member of the Swedish establishment, Linnaeus began to reap honours. In 1753, he was the first Swedish scientist to be recognized with the award of the Order of the Polar Star, and, in 1762, he was made a Lord, styling himself von Linné.

Yet he never escaped his humble origins, being compared by one of the more urbane members of the Swedish court to a “hearty and energetic provincial governor.” One visiting naturalist described him as “somewhat aged, not a large man with dusty shoes and stockings, markedly unshaven and dressed in an old green coat from which dangles a medal.” After a series of debilitating strokes, he died in 1778 aged 71. His son, also Carl, inherited his professorship at Uppsala but the dynasty did not last long as Carl Jr. died just 5 years later. Ironically, given Linnaeus’ fierce devotion to Sweden, his collections, manuscripts and library were bought shortly after Carl Jr.’s death by an Englishman, James Edward Smith. In 1788, Smith founded the Linnean Society of London.

Since 1986, he is on the Swedish 100-kronor note.