by What Linnaeus Saw- A Scientist's Quest to Name Every Living Thing (retail) (epub)
A few years later, in 1749, he studied coastal geology, as he journeyed through Sweden’s southernmost province, Skåne, to survey its natural resources. North of Helsingborg, across the sound from Denmark, he counted the sedimentary strata exposed on a unique rock cliff by the sea. Linnaeus expressed amazement at the amount of time it would have taken for those layers to build up:
I feel dizzy when I stand upon this hill and look down upon the long period of time which has passed like waves in the Sound, leaving behind only these faintest traces of the former world, and which can now only whisper when all else has become still.
The age of the earth was a hotly debated subject in the eighteenth century. Linnaeus and his European contemporaries were aware of Chinese estimates based on the recorded succession of their emperors that dated back 30,000 to 60,000 years, making the earth five to ten times older than the six thousand years estimated by biblical scholars. Cautious of questions that could put science and religion into conflict, Linnaeus wrote in an autobiography that he “would gladly have believed that the earth was older than the Chinese had claimed, had the Holy Scriptures suffered it.” Using today’s advanced technologies, scientists have dated those sedimentary strata exposed on the Helsingborg cliff back to the Jurassic Period, more than 150 million years ago.
Despite his great interest in animals and minerals, Linnaeus’s true passion since boyhood was the study of plants. For the plant kingdom he created a four-step system of classification.
First, he divided all plants into twenty-four broad classes. One class included plants without flowers; the rest, the flowering plants, he sorted into twenty-three classes according to the number and arrangement of their stamens.
Second, he divided each of the classes into smaller groups, called orders, by the number and arrangement of their pistils. It was convenient. Mathematical. Anybody could follow these first two steps simply by closely observing and counting the stamens and then the pistils.
Third, he divided each of the orders into the even smaller groups which Tournefort had called genera. Linnaeus kept most of the Frenchman’s one-word genus names.
In the fourth and final step, he divided each genus into species, thus differentiating every specific type of plant from all the others.
For example, the pumpkin. If Linnaeus was looking at it for the first time, he would see that this type of squash was a flowering plant. When he went to count the stamens and pistils, he would see that they were located in different flowers on the same vine. Therefore it belonged in the class Monoecia, meaning “one house,” with male and female flowers growing on the same plant. When male and female flowers grew on separate plants, they belonged to a class he called Dioecia, or “two houses.”
Linnaeus’s design for a tall cupboard to hold 6,000 sheets of pressed plants. He had three cupboards built, into which he sorted the plants according to their classes on shelves labeled I to XXIV.
One of his original cupboards is on display in his hilltop museum at Hammarby.
Linnaeus placed the dried pumpkin plant specimen on shelf XXI of his tall gray cabinet, with cucumbers, squash, melons, and all the other monoecious plants which had male and female flowers on the same plant.
The tulip has six stamens, so he placed it in the class Hexandria. The banana flower also has six stamens and joined the tulip on shelf VI. The holly, however, grows male and female flowers on completely separate plants, putting it in the class with the other dioecious plants. Linnaeus placed it on shelf XXII.
He called this plant classification system his “autopsy” of nature.
To make ideas memorable for his readers, Linnaeus used colorful metaphors. For instance, he imagined the plant kingdom as the temple of the goddess Flora, her head crowned with flowers. And when, during his travels in Sápmi, he spotted a pink-flowered plant growing on a rock in a marsh, and beneath it a newt, he named the plant Andromeda, after the mythical princess chained to a rock in the ocean guarded by a sea monster.
His fanciful analogies amused some people, but others were offended by the sexual references when he took the analogy to extremes. He compared plant reproduction with marriage—stamens as husbands and pistils as wives, petals as the bridal chamber. For instance, the class Monandria was “one husband in a marriage,” Diandria was “two husbands in the same marriage,” and when he reached Polyandria, an arrangement typical in poppy plants and linden trees, the analogy became “twenty males or more in the same bed with the female.”
He explained his flowery analogy, writing that “The flowers’ leaves . . . serve as bridal beds which the Creator has so gloriously arranged, adorned with such noble bed curtains, and perfumed with so many soft scents that the bridegroom with his bride might celebrate their nuptials with so much the greater solemnity. When now the bed is so prepared, it is time for the bridegroom to embrace his beloved bride and offer her his gifts.”
HOW LINNAEUS ORGANIZED PLANTS INTO CLASSES
To show the basics of this method, this chart lists examples of plants in each class by their current scientific and common names. Linnaeus’s numerals correspond with Ehret’s letters on the poster on page 124.
NUMBER OR ARRANGEMENT OF STAMENS CLASS SPECIES EXAMPLES
1 I. Monandria Hippuris vulgaris (common mare’s tail)
2 II. Diandria Syringa vulgaris (common lilac)
3 III. Triandria Avena sativa (common oat); Iris versicolor (blue flag)
4 IV. Tetrandria Cornus florida (flowering dogwood)
5 V. Pentandria Myosotis palustris (true forget-me-knot); Limonium angustatum (Carolina sea-lavender)
6: either equal, or if unequal having 3 long and 3 short stamens VI. Hexandria Trillium grandiflorum (white trillium); Yucca glauca (yucca or soapweed)
7 VII. Heptandria Aesculus glabra (Ohio buckeye)
8 VIII. Octandria Vaccinium angustifolium (lowbush blueberry); Tropaeolum majus (garden nasturtium or Indian cress)
9 IX. Enneandria Rheum rhabarbarum (garden rhubarb)
10 or 11 X. Decandria Kalmia latifolia (mountain laurel); Sedum spathulifolium (broadleaf stonecrop)
12–19 XI. Dodecandria Sempervivum globiferum (hens and chicks; hen-widdies)
20 or more, filaments attached to calyx XII. Icosandria Carnegiea gigantea (saguaro cactus); Rosa arkansana (wild prairie rose)
20 or more, filaments not attached to calyx XIII.Polyandria Magnolia grandiflora (southern magnolia); Eschscholzia californica (California poppy); Aquilegia coerulea (Colorado columbine)
Stamens of markedly unequal length:
2 long and 2 short XIV. Didynamia Mentha arvensis (wild mint); Linaria vulgaris (butter-and-eggs)
4 long and 2 short XV. Tetradynamia Nasturtium officinale (watercress)
Stamens united in the filaments or anthers:
Stamens in one group or bundle XVI. Monadelphia Camellia japonica (camellia); Thespesia grandiflora (amapola); Hibiscus brackenridgei (pua aloalo)
Stamens in 2 groups XVII. Diadelphia Trifolium pratense (red clover); Lupinus texensis (bluebonnet)
Stamens in 3 or more groups XVIII. Polyadelphia Citrus sinenis (sweet orange)
Union of stamens confined to anthers XIX. Syngenesia Helianthus annuus (common sunflower); Viola sororia (common blue violet); Taraxacum officinale (common dandelion)
Stamens united with the pistil XX. Gynandria Passiflora incarnata (passionflower); Cypripedium acaule (pink lady slipper)
Stamens and pistils in different flowers:
Male and female flowers on the same plant XXI. Monoecia Cucurbita pepo (pumpkin); Quercus alba (white oak)
Male and female flowers on different plants XXII. Dioecia Populus deltoides (Eastern cottonwood); Ilex opaca (American holly)
Male and female flowers mixed with hermaphrodite flowers XXIII. Polygamia Musa acuminata (banana); Acer saccharum (sugar maple)
No stamens:
These plants have no proper flowers and reproduce with spores XXIV. Cryptogamia (ferns, mosses, algae, lichens, fungi, mus
hrooms) Osmundastrum cinnamomeum (cinnamon fern)
The names of most of his plant classes ended in “-andria,” from the Greek word for “man”—Monandria, Diandria, Triandria. In this system, based on counting parts of the plant, the prefix was the total count: “mono-” (one), “di-” (two), “tri-” (three), and so on. The names of his plant orders ended in “-gynia,” from the Greek for “woman”—Monogynia, Digynia, Trigynia. Cryptogamia—ferns, mosses, algae, and fungi—were “plants that marry secretly.”
His so-called sexual system of plants turned a once-friendly correspondent, Johann Siegesbeck, director of the botanic garden in St. Petersburg, Russia, into a fierce and bitter critic. Calling it “lewd,” Siegesbeck lashed out, saying, “Who would have thought that bluebells and lilies and onions could be up to such immorality?”
Linnaeus was extremely sensitive to criticism. He felt deeply stung and sought advice. A mentor urged him to never respond to critics. Linnaeus said nothing, but still could not resist temptation. On a packet of seeds that he’d named Sigesbeckia [sic] orientalis to honor Siegesbeck long before their fight, he now scrawled a new label—“Cuculus ingratus,” meaning “ungrateful cuckoo.” The packet made its way to the St. Petersburg Botanic Garden mixed in with other packets in a box that one of Linnaeus’s students intended to trade for Russian seeds—and into the hands of Johann Siegesbeck. However, the feud did not stop there. In 1752, Linnaeus would rank the officers in “Flora’s army.” General Linnaeus put himself at the top, followed by various botanists as major generals, colonels, and chief officers. At the bottom was Sergeant-Major Siegesbeck.
Generally, though, when Linnaeus’s fellow scientists saw the ease and practicality of his plant system, they began to use it. One fan, Jan Frederik Gronovius, who’d helped to finance the first edition of Systema Naturae, wrote to a colleague about the charts saying, “everybody ought to have them hanging in his study, like maps.” This idea became reality when Georg Ehret painted a handsome poster which made the system’s elegant simplicity even easier to grasp. The artist sold copies of his poster for two Dutch guilders. Every botanist in Holland bought a copy.
When Linnaeus published Ehret’s poster in his book Genera Plantarum (The genera of plants), he used it without permission and failed to give the artist credit or payment. This unfair practice was common at the time. Ehret later griped that “When he was a beginner, [Linnaeus] appropriated everything for himself which he heard of, to make himself famous.” Despite this, Ehret, who had similar grievances with other employers, remained friends with Linnaeus throughout his life.
Linnaeus wanted everybody to be able to learn about botany whether they were wealthy and educated or penniless and untrained, as he was as a boy.
His first-year university students often came to him with no previous education in science and little access to illustrated botany books. He worked hard to make his writing clear, concise, and in the simplest Latin. He avoided expensive copper-engraved images to keep costs low, so that each student could afford his own copy. One book, for instance, he insisted be priced at only two and a half shillings. Although this amount represented a few days’ wages for most people, it was a small price compared with other books of the time.
Georg Dionysus Ehret’s original hand-colored, engraved poster showing Linnaeus’s system for classifying plants. Only this original drawing and two of the printed posters still exist.
Many of his books were short, easy to read, and compact—small enough to carry into the field. He published plant diagrams, as well as practical one-page instructions on how to plant a garden, set up a herbarium, pack seeds and live specimens for shipping, organize a field trip, and prepare for an expeditionary voyage.
His wildly popular plan for a “flower clock” reached an even wider audience of non-scientists. It was supposed to tell the time of day by the opening and closing of particular flower species, although different latitudes and seasonal variations made it impractical. Even so, many people had fun experimenting with it in their gardens.
Not all scientists were happy to have uneducated home gardeners and women dabbling in their profession. But Linnaeus was a science popularizer. He believed that even those not academically trained in science could be excited about nature.
Meanwhile, Linnaeus continued building his worldwide network of prolific letter-writing scientists, a network he started with contacts from George Clifford’s botanical exchange. Correspondents from many countries, including botanists in charge of major European botanical gardens as well as amateur collectors, swapped plants with him and, in lengthy letters, debated ideas. In their letters back and forth, they greeted each other with extravagant compliments, following the custom of the day. However, as Linnaeus’s student Johan Christian Fabricius observed, “He was generous with his praise because he himself loved to be flattered.”
From the North American colonies, Alexander Garden, a medical doctor in South Carolina, corresponded with Linnaeus, as did John Bartram, a mostly self-educated botanist in Pennsylvania who ran a brisk global plant trade, even though he couldn’t read Latin. Another correspondent, Cadwallader Colden, originally from Scotland, was a physician, surveyor, and New York’s colonial lieutenant governor. He and his family lived on a 3,000-acre farm in the wilderness of the Hudson River highlands, sixty miles north of Manhattan. There, Colden translated Linnaeus’s botanical Latin into English for his teenage daughter.
Like most women of her time, Jane Colden was never given the opportunity to attend school. But living in the wilderness, instructed and encouraged by her two well-educated parents, she became a skilled and careful observer. Once she mastered the Linnaean system, she quickly surpassed her father in botanical ability. John Bartram sent his son, William, to the Colden estate for a summer to learn about plants from her. Bartram and others praised her in letters to Linnaeus. She drew the plants and used the correct Linnaean names to describe dwarf ginseng, sarsaparilla, yellow lady’s slipper, crinkleroot, blue lupine, goldthread, and some four hundred native plants on her family’s land.
Drawings in Jane Colden’s botanical journal, including the plant goldthread.
Jane Colden was America’s first female botanist. Linnaeus’s friend Peter Collinson, an amateur naturalist and London merchant with business connections in North America, wrote that she was “perhaps the only lady that makes profession of the Linnaean system.” John Ellis, another British merchant, naturalist and a regular correspondent of Linnaeus’s, believed that she had discovered a new species which she had called Fibraurea (goldthread). He and the others urged Linnaeus to name the plant after her. Coldenella, they suggested. “She deserves to be celebrated,” Collinson wrote. It turned out that the plant had been discovered previously and had a name: Helleborus.
NATURAL VS. ARTIFICIAL
Linnaeus always knew that parts of his classification system were artificial: that is, not based on nature. His goal had always been a system based on natural relationships, but there were gaps in his knowledge that he knew created weaknesses in his system. Imperfect as it was, it stabilized science and gave the scientists who followed him time to collect more information and fix its weaknesses.
Within a few years of Linnaeus’s death, scientists had replaced the more artificial parts of his system, responding to new facts. They added levels to his hierarchy, which now runs, from largest grouping to smallest: kingdom, phylum, class, order, family, genus, species, and subspecies.
Although Linnaeus’s original, artificial system is no longer used, scientists still use his basic hierarchy and binomial nomenclature. His work enabled others to move forward with new and pioneering ideas that would eventually include evolution. Today, new technologies are helping scientists to better understand species and their genetic relationships. They are using new technologies to work toward a truly natural system—just as Linnaeus had hoped to create.
One of the very few women for whom Linnaeus named a plant genus was Lady Anne Monson. This English botanist, who l
ived in Calcutta, India, and had collected plants with Linnaeus’s student Carl Peter Thunberg at the Cape of Good Hope, shipped specimens from her collections to Linnaeus. He named one of them Monsonia.
In all, Linnaeus exchanged more than four thousand letters, plus seeds and specimens, with six hundred correspondents.
By the 1740s, Linnaeus’s organizing system was attracting people of all ranks and means in many countries. He was helping to make nature study popular across the world. However, as he and his students worked with his two-step process of organizing and naming, they ran into a snag. Long, convoluted Latin names were slowing down everyone’s fieldwork. Step two—naming—proved to be Linnaeus’s next dilemma. It was a problem he needed to fix.
7
LAST NAME, FIRST NAME
The shorter the specific name, the better . . . it is foolish to do in more [words] what can be done by fewer.
—CARL LINNAEUS, PRINCIPLE NO. 291, PHILOSOPHIA BOTANICA (THE SCIENCE OF BOTANY), 1751
For thousands of years, people have given names to living things to identify individuals from the rest of a group. They are often two words. Shasta daisy. Woolly mammoth. German shepherd. Poison ivy. Silver birch. Norway spruce. Swedish ivy. Alpine gentian. Lapland rosebay. Lapland buttercup. Glacier buttercup.
These common names are almost always different among people who speak different languages. But even people who live just a few miles apart can have different names for the very same thing. One person’s mountain lion is another person’s cougar—and somebody else’s puma.
