references to “promiscuous intercourse,” “barren concubines,” and “the bridal bed.” In spring, he wrote in one oft- quoted passage:
Love comes even to the plants. Males and females . . . hold their nuptials . . . showing by their sexual organs which are males, which females. The flowers’ leaves serve as a bridal bed, 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 there celebrate their nuptials with so much the greater solemnity. When the bed has thus been made ready, then is the time for the bridegroom to embrace his beloved bride and surrender himself to her.
He named one genus of plants Clitoria. Not surprisingly, many people thought him strange. But his system of classification was irresistible. Before Linnaeus, plants were given names that were expansively descriptive. The common ground cherry was called Physalis amno ramosissime ramis angulosis glabris foliis dentoserratis. Linnaeus lopped it back to Physalis angulata, which name it still uses. The plant world was equally disordered by inconsistencies of naming. A botanist could not be sure if Rosa sylvestris alba cum rubore, folio glabro was the same plant that others called Rosa sylvestris inodora seu canina. Linnaeus solved the puzzlement by calling it simply Rosa canina. To make these excisions useful and agreeable to all required much more than simply being decisive. It required an instinct-a genius, in fact-for spotting the salient qualities of a species.
The Linnaean system is so well established that we can hardly imagine an alternative, but before Linnaeus, systems of classification were often highly whimsical. Animals might be categorized by whether they were wild or domesticated, terrestrial or aquatic, large or small, even whether they were thought handsome and noble or of no consequence. Buffon arranged his animals by their utility to man. Anatomical considerations barely came into it. Linnaeus made it his life’s work to rectify this deficiency by classifying all that was alive according to its physical attributes. Taxonomy-which is to say the science of classification-has never looked back.
It all took time, of course. The first edition of his great Systema Naturae in 1735 was just fourteen pages long. But it grew and grew until by the twelfth edition-the last that Linnaeus would live to see-it extended to three volumes and 2,300 pages. In the end he named or recorded some 13,000 species of plant and animal. Other works were more comprehensive-John Ray’s three-volume Historia Generalis Plantarum in England, completed a generation earlier, covered no fewer than 18,625 species of plants alone-but what Linnaeus had that no one else could touch were consistency, order, simplicity, and timeliness. Though his work dates from the 1730s, it didn’t become widely known in England until the 1760s, just in time to make Linnaeus a kind of father figure to British naturalists. Nowhere was his system embraced with greater enthusiasm (which is why, for one thing, the Linnaean Society has its home in London and not Stockholm).
Linnaeus was not flawless. He made room for mythical beasts and “monstrous humans” whose descriptions he gullibly accepted from seamen and other imaginative travelers. Among these were a wild man, Homo ferus, who walked on all fours and had not yet mastered the art of speech, and Homo caudatus, “man with a tail.” But then it was, as we should not forget, an altogether more credulous age. Even the great Joseph Banks took a keen and believing interest in a series of reported sightings of mermaids off the Scottish coast at the end of the eighteenth century. For the most part, however, Linnaeus’s lapses were offset by sound and often brilliant taxonomy. Among other accomplishments, he saw that whales belonged with cows, mice, and other common terrestrial animals in the order Quadrupedia (later changed to Mammalia), which no one had done before.
In the beginning, Linnaeus intended only to give each plant a genus name and a number- Convolvulus 1, Convolvulus 2, and so on-but soon realized that that was unsatisfactory and hit on the binomial arrangement that remains at the heart of the system to this day. The intention originally was to use the binomial system for everything-rocks, minerals, diseases, winds, whatever existed in nature. Not everyone embraced the system warmly. Many were disturbed by its tendency toward indelicacy, which was slightly ironic as before Linnaeus the common names of many plants and animals had been heartily vulgar. The dandelion was long popularly known as the “pissabed” because of its supposed diuretic properties, and other names in everyday use included mare’s fart, naked ladies, twitch-ballock, hound’s piss, open arse, and bum-towel. One or two of these earthy appellations may unwittingly survive in English yet. The “maidenhair” in maidenhair moss, for instance, does not refer to the hair on the maiden’s head. At all events, it had long been felt that the natural sciences would be appreciably dignified by a dose of classical renaming, so there was a certain dismay in discovering that the self-appointed Prince of Botany had sprinkled his texts with such designations as Clitoria, Fornicata, and Vulva.
Over the years many of these were quietly dropped (though not all: the common slipper limpet still answers on formal occasions to Crepidula fornicata) and many other refinements introduced as the needs of the natural sciences grew more specialized. In particular the system was bolstered by the gradual introduction of additional hierarchies. Genus (plural genera) and species had been employed by naturalists for over a hundred years before Linnaeus, and order, class, and family in their biological senses all came into use in the 1750s and 1760s. But phylum wasn’t coined until 1876 (by the German Ernst Haeckel), and family and order were treated as interchangeable until early in the twentieth century. For a time zoologists used family where botanists placed order, to the occasional confusion of nearly everyone.[36]
Linnaeus had divided the animal world into six categories: mammals, reptiles, birds, fishes, insects, and “vermes,” or worms, for everything that didn’t fit into the first five. From the outset it was evident that putting lobsters and shrimp into the same category as worms was unsatisfactory, and various new categories such as Mollusca and Crustacea were created. Unfortunately these new classifications were not uniformly applied from nation to nation. In an attempt to reestablish order, the British in 1842 proclaimed a new set of rules called the Stricklandian Code, but the French saw this as highhanded, and the Societe Zoologique countered with its own conflicting code. Meanwhile, the American Ornithological Society, for obscure reasons, decided to use the 1758 edition of Systema Naturae as the basis for all its naming, rather than the 1766 edition used elsewhere, which meant that many American birds spent the nineteenth century logged in different genera from their avian cousins in Europe. Not until 1902, at an early meeting of the International Congress of Zoology, did naturalists begin at last to show a spirit of compromise and adopt a universal code.
Taxonomy is described sometimes as a science and sometimes as an art, but really it’s a battleground. Even today there is more disorder in the system than most people realize. Take the category of the phylum, the division that describes the basic body plans of all organisms. A few phyla are generally well known, such as mollusks (the home of clams and snails), arthropods (insects and crustaceans), and chordates (us and all other animals with a backbone or protobackbone), though things then move swiftly in the direction of obscurity. Among the latter we might list Gnathostomulida (marine worms), Cnidaria (jellyfish, medusae, anemones, and corals), and the delicate Priapulida (or little “penis worms”). Familiar or not, these are elemental divisions. Yet there is surprisingly little agreement on how many phyla there are or ought to be. Most biologists fix the total at about thirty, but some opt for a number in the low twenties, while Edward O. Wilson in The Diversity of Life puts the number at a surprisingly robust eighty-nine. It depends on where you decide to make your divisions-whether you are a “lumper” or a “splitter,” as they say in the biological world.
At the more workaday level of species, the possibilities for disagreements are even greater. Whether a species of grass should be called Aegilops incurva, Aegilops incurvata, or Aegilops ovata may not be a matter that would stir many nonbotanists to passion, but it can be a source of very lively heat in the right quarters. The problem is that there are five thousand species of grass and many of them look awfully alike even to people who know grass. In consequence, some species have been found and named at least twenty times, and there are hardly any, it appears, that haven’t been independently
