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r spotting the salient qualities of a species。
the linnaean system is so well established that we can hardly imagine an alternative； butbefore linnaeus； systems of classification were often highly whimsical。 animals might becategorized 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 arrangedhis animals by their utility to man。 anatomical considerations barely came into it。 linnaeus made it his life鈥檚 work to rectify this deficiency by classifying all that was alive according toits physical attributes。 taxonomy鈥攚hich is to say the science of classification鈥攈as neverlooked back。
it all took time； of course。 the first edition of his great systema naturae in 1735 was justfourteen pages long。 but it grew and grew until by the twelfth edition鈥攖he last that linnaeuswould live to see鈥攊t extended to three volumes and 2；300 pages。 in the end he named orrecorded some 13；000 species of plant and animal。 other works were more prehensive鈥攋ohn ray鈥檚 three…volume historia generalis plantarum in england； pleted a generationearlier； covered no fewer than 18；625 species of plants alone鈥攂ut what linnaeus had that noone else could touch were consistency； order； simplicity； and timeliness。 though his workdates from the 1730s； it didn鈥檛 bee widely known in england until the 1760s； just in timeto make linnaeus a kind of father figure to british naturalists。 nowhere was his systemembraced with greater enthusiasm （which is why； for one thing； the linnaean society has itshome in london and not stockholm）。
linnaeus was not flawless。 he made room for mythical beasts and 鈥渕onstrous humans鈥�
whose descriptions he gullibly accepted from seamen and other imaginative travelers。 amongthese were a wild man； homo ferus； who walked on all fours and had not yet mastered the artof speech； and homo caudatus； 鈥渕an with a tail。鈥潯ut then it was； as we should not forget； analtogether more credulous age。 even the great joseph banks took a keen and believing interestin a series of reported sightings of mermaids off the scottish coast at the end of the eighteenthcentury。 for the most part； however； linnaeus鈥檚 lapses were offset by sound and oftenbrilliant taxonomy。 among other acplishments； he saw that whales belonged with cows；mice； and other mon terrestrial animals in the order quadrupedia （later changed tomammalia）； which no one had done before。
in the beginning； linnaeus intended only to give each plant a genus name and a number鈥攃onvolvulus 1； convolvulus 2；and so on鈥攂ut soon realized that that was unsatisfactory andhit on the binomial arrangement that remains at the heart of the system to this day。 theintention originally was to use the binomial system for everything鈥攔ocks； minerals； diseases；winds； whatever existed in nature。 not everyone embraced the system warmly。 many weredisturbed by its tendency toward indelicacy； which was slightly ironic as before linnaeus themon names of many plants and animals had been heartily vulgar。 the dandelion was longpopularly known as the 鈥減issabed鈥潯ecause of its supposed diuretic properties； and othernames in everyday use included mare鈥檚 fart； naked ladies； twitch…ballock； hound鈥檚 piss； openarse； and bum…towel。 one or two of these earthy appellations may unwittingly survive inenglish yet。 the 鈥渕aidenhair鈥潯n maidenhair moss； for instance； does not refer to the hair onthe maiden鈥檚 head。 at all events； it had long been felt that the natural sciences would beappreciably dignified by a dose of classical renaming； so there was a certain dismay indiscovering that the self…appointed prince of botany had sprinkled his texts with suchdesignations asclitoria； fornicata； andvulva。
over the years many of these were quietly dropped （though not all： the mon slipperlimpet still answers on formal occasions to crepidula fornicata） and many other refinementsintroduced as the needs of the natural sciences grew more specialized。 in particular the systemwas bolstered by the gradual introduction of additional hierarchies。genus （pluralgenera） andspecies had been employed by naturalists for over a hundred years before linnaeus； andorder； class； and family in their biological senses all came into use in the 1750s and 1760s。
but phylum wasn鈥檛 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 usedfamily where botanists placed order； to the occasional confusion of nearly everyone。
1linnaeus had divided the animal world into six categories： mammals； reptiles； birds； fishes；insects； and 鈥渧ermes；鈥潯r worms； for everything that didn鈥檛 fit into the first five。 from theoutset it was evident that putting lobsters and shrimp into the same category as worms wasunsatisfactory； and various new categories such as mollusca and crustacea were created。
unfortunately these new classifications were not uniformly applied from nation to nation。 inan attempt to reestablish order； the british in 1842 proclaimed a new set of rules called thestricklandian code； but the french saw this as highhanded； and the soci茅t茅 zoologiquecountered with its own conflicting code。 meanwhile； the american ornithological society； forobscure reasons； decided to use the 1758 edition of systema naturae as the basis for all itsnaming； rather than the 1766 edition used elsewhere； which meant that many american birdsspent 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 naturalistsbegin at last to show a spirit of promise and adopt a universal code。
taxonomy is described sometimes as a science and sometimes as an art； but really it鈥檚 abattleground。 even today there is more disorder in the system than most people realize。 takethe 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 backboneor protobackbone）； though things then move swiftly in the direction of obscurity。 among thelatter we might list gnathostomulida （marine worms）； cnidaria （jellyfish； medusae；anemones； and corals）； and the delicate priapulida （or little 鈥減enis worms鈥潱！amiliar or not；these are elemental divisions。 yet there is surprisingly little agreement on how many phylathere are or ought to be。 most biologists fix the total at about thirty； but some opt for a numberin the low twenties； while edward o。 wilson in the diversity of life puts the number at asurprisingly robust eighty…nine。 it depends on where you decide to make your divisions鈥攚hether you are a 鈥渓umper鈥潯r a 鈥渟plitter；鈥潯s 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 aegilopsovata may not be a matter that would stir many nonbotanists to passion； but it can be a sourceof very lively heat in the right quarters。 the problem is that there are five thousand species ofgrass 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； itappears； that haven鈥檛 been independently identified at least twice。 the two…volume manual ofthe grasses of the united states devotes two hundred closely typeset pages to sorting out allthe synonymies； as the biological world refers to its inadvertent but quite monduplications。 and that is just for the grasses of a single country。
to deal with disagreements on the global stage； a body known as the internationalassociation for plant taxonomy arbitrates on questions of priority and duplication。 at1to illustrate； humans are in the domain eucarya； in the kingdom animalia； in the phylum chordata； in thesubphylum vertebrata； in the class mammalia； in the order primates； in the family hominidae； in the genus homo；in the species sapiens。 （the convention； im informed； is to italicize genus and species names； but not those ofhigher divisions。） some taxonomists employ further subdivisions： tribe； suborder； infraorder； parvorder； andmore。
intervals it hands down decrees； declaring that zauschneria californica （a mon plant inrock gardens） is to be known henceforth as epilobium canum or that aglaothamniontenuissimum may now be regarded as conspecific with aglaothamnion byssoides； but notwithaglaothamnion pseudobyssoides。 normally these are small matters of tidying up thatattract little notice； but when they touch on beloved garden plants； as they sometimes do；shrieks of outrage inevitably follow。 in the late 1980s the mon chrysanthemum wasbanished （on apparently sound scientific principles） from the genus of the same name andrelegated to the paratively drab and undesirable world of the genus dendranthema。
chrysanthemum breeders are a proud and numerous lot； and they protested to the real ifimprobable…sounding mittee on spermatophyta。 （the