23 THE RICHNESS OF BEING
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The Natural History Museum contains some seventy million objects from every realm oflife and every corner of the planet, with another hundred thousand or so added to thecollection each year, but it is really only behind the scenes that you get a sense of what atreasure house this is. In cupboards and cabinets and long rooms full of close-packed shelvesare kept tens of thousands of pickled animals in bottles, millions of insects pinned to squaresof card, drawers of shiny mollusks, bones of dinosaurs, skulls of early humans, endlessfolders of neatly pressed plants. It is a little like wandering through Darwin’s brain. The spiritroom alone holds fifteen miles of shelving containing jar upon jar of animals preserved inmethylated spirit.
Back here are specimens collected by Joseph Banks in Australia, Alexander von Humboldtin Amazonia, Darwin on the Beagle voyage, and much else that is either very rare orhistorically important or both. Many people would love to get their hands on these things. Afew actually have. In 1954 the museum acquired an outstanding ornithological collection fromthe estate of a devoted collector named Richard Meinertzhagen, author of Birds of Arabia,among other scholarly works. Meinertzhagen had been a faithful attendee of the museum foryears, coming almost daily to take notes for the production of his books and monographs.
When the crates arrived, the curators excitedly jimmied them open to see what they had beenleft and were surprised, to put it mildly, to discover that a very large number of specimensbore the museum’s own labels. Mr. Meinertzhagen, it turned out, had been helping himself totheir collections for years. It also explained his habit of wearing a large overcoat even duringwarm weather.
A few years later a charming old regular in the mollusks department—“quite a distinguishedgentleman,” I was told—was caught inserting valued seashells into the hollow legs of hisZimmer frame.
“I don’t suppose there’s anything in here that somebody somewhere doesn’t covet,”
Richard Fortey said with a thoughtful air as he gave me a tour of the beguiling world that isthe behind-the-scenes part of the museum. We wandered through a confusion of departmentswhere people sat at large tables doing intent, investigative things with arthropods and palm fronds and boxes of yellowed bones. Everywhere there was an air of unhurried thoroughness,of people being engaged in a gigantic endeavor that could never be completed and mustn’t berushed. In 1967, I had read, the museum issued its report on the John Murray Expedition, anIndian Ocean survey, forty-four years after the expedition had concluded. This is a worldwhere things move at their own pace, including a tiny lift Fortey and I shared with a scholarlylooking elderly man with whom Fortey chatted genially and familiarly as we proceededupwards at about the rate that sediments are laid down.
When the man departed, Fortey said to me: “That was a very nice chap named Normanwho’s spent forty-two years studying one species of plant, St. John’s wort. He retired in 1989,but he still comes in every week.”
“How do you spend forty-two years on one species of plant?” I asked.
“It’s remarkable, isn’t it?” Fortey agreed. He thought for a moment. “He’s very thoroughapparently.” The lift door opened to reveal a bricked-over opening. Fortey lookedconfounded. “That’s very strange,” he said. “That used to be Botany back there.” He puncheda button for another floor, and we found our way at length to Botany by means of backstaircases and discreet trespass through yet more departments where investigators toiledlovingly over once-living objects. And so it was that I was introduced to Len Ellis and thequiet world of bryophytes—mosses to the rest of us.
When Emerson poetically noted that mosses favor the north sides of trees (“The moss uponthe forest bark, was pole-star when the night was dark”) he really meant lichens, for in thenineteenth century mosses and lichens weren’t distinguished. True mosses aren’t actuallyfussy about where they grow, so they are no good as natural compasses. In fact, mosses aren’tactually much good for anything. “Perhaps no great group of plants has so few uses,commercial or economic, as the mosses,” wrote Henry S. Conard, perhaps just a touch sadly,in How to Know the Mosses and Liverworts, published in 1956 and still to be found on manylibrary shelves as almost the only attempt to popularize the subject.
They are, however, prolific. Even with lichens removed, bryophytes is a busy realm, withover ten thousand species contained within some seven hundred genera. The plump andstately Moss Flora of Britain and Ireland by A. J. E. Smith runs to seven hundred pages, andBritain and Ireland are by no means outstandingly mossy places. “The tropics are where youfind the variety,” Len Ellis told me. A quiet, spare man, he has been at the Natural HistoryMuseum for twenty-seven years and curator of the department since 1990. “You can go outinto a place like the rain forests of Malaysia and find new varieties with relative ease. I didthat myself not long ago. I looked down and there was a species that had never beenrecorded.”
“So we don’t know how many species are still to be discovered?”
“Oh, no. No idea.”
You might not think there would be that many people in the world prepared to devotelifetimes to the study of something so inescapably low key, but in fact moss people number inthe hundreds and they feel very strongly about their subject. “Oh, yes,” Ellis told me, “themeetings can get very lively at times.”
I asked him for an example of controversy.
“Well, here’s one inflicted on us by one of your countrymen,” he said, smiling lightly, andopened a hefty reference work containing illustrations of mosses whose most notablecharacteristic to the uninstructed eye was their uncanny similarity one to another. “That,” hesaid, tapping a moss, “used to be one genus, Drepanocladus. Now it’s been reorganized intothree: Drepanocladus, Wamstorfia, and Hamatacoulis.”
“And did that lead to blows?” I asked perhaps a touch hopefully.
“Well, it made sense. It made perfect sense. But it meant a lot of reordering of collectionsand it put all the books out of date for a time, so there was a bit of, you know, grumbling.”
Mosses offer mysteries as well, he told me. One famous case—famous to moss peopleanyway—involved a retiring type called Hyophila stanfordensis, which was discovered on thecampus of Stanford University in California and later also found growing beside a path inCornwall, on the southwest tip of England, but has never been encountered anywhere inbetween. How it came to exist in two such unconnected locations is anybody’s guess. “It’snow known as Hennediella stanfordensis,” Ellis said. “Another revision.”
We nodded thoughtfully.
When a new moss is found it must be compared with all other mosses to make sure that ithasn’t been recorded already. Then a formal description must be written and illustrationsprepared and the result published in a respectable journal. The whole process seldom takesless than six months. The twentieth century was not a great age for moss taxonomy. Much ofthe century’s work was devoted to untangling the confusions and duplications left behind bythe nineteenth century.
That was the golden age of moss collecting. (You may recall that Charles Lyell’s fatherwas a great moss man.) One aptly named Englishman, George Hunt, hunted British mosses soassiduously that he probably contributed to the extinction of several species. But it is thanksto such efforts that Len Ellis’s collection is one of the world’s most comprehensive. All780,000 of his specimens are pressed into large folded sheets of heavy paper, some very oldand covered with spidery Victorian script. Some, for all we knew, might have been in thehand of Robert Brown, the great Victorian botanist, unveiler of Brownian motion and thenucleus of cells, who founded and ran the museum’s botany department for its first thirty-oneyears until his death in 1858. All the specimens are kept in lustrous old mahogany cabinets sostrikingly fine that I remarked upon them.
“Oh, those were Sir Joseph Banks’s, from his house in Soho Square,” Ellis said casually, asif identifying a recent purchase from Ikea. “He had them built to hold his specimens from theEndeavour voyage.” He regarded the cabinets thoughtfully, as if for the first time in a longwhile. “I don’t know howwe ended up with them in bryology,” he added.
This was an amazing disclosure. Joseph Banks was England’s greatest botanist, and theEndeavour voyage—that is the one on which Captain Cook charted the 1769 transit of Venusand claimed Australia for the crown, among rather a lot else—was the greatest botanicalexpedition in history. Banks paid ￡10,000, about $1 million in today’s money, to bringhimself and a party of nine others—a naturalist, a secretary, three artists, and four servants—on the three-year adventure around the world. Goodness knows what the bluff Captain Cook made of such a velvety and pampered assemblage, but he seems to have liked Banks wellenough and could not but admire his talents in botany—a feeling shared by posterity.
Never before or since has a botanical party enjoyed greater triumphs. Partly it was becausethe voyage took in so many new or little-known places—Tierra del Fuego, Tahiti, NewZealand, Australia, New Guinea—but mostly it was because Banks was such an astute andinventive collector. Even when unable to go ashore at Rio de Janeiro because of a quarantine,he sifted through a bale of fodder sent for the ship’s livestock and made new discoveries.
Nothing, it seems, escaped his notice. Altogether he brought back thirty thousand plantspecimens, including fourteen hundred not seen before—enough to increase by about aquarter the number of known plants in the world.
But Banks’s grand cache was only part of the total haul in what was an almost absurdlyacquisitive age. Plant collecting in the eighteenth century became a kind of internationalmania. Glory and wealth alike awaited those who could find new species, and botanists andadventurers went to the most incredible lengths to satisfy the world’s craving for horticulturalnovelty. Thomas Nuttall, the man who named the wisteria after Caspar Wistar, came toAmerica as an uneducated printer but discovered a passion for plants and walked halfwayacross the country and back again, collecting hundreds of growing things never seen before.
John Fraser, for whom is named the Fraser fir, spent years in the wilderness collecting onbehalf of Catherine the Great and emerged at length to find that Russia had a new czar whothought he was mad and refused to honor his contract. Fraser took everything to Chelsea,where he opened a nursery and made a handsome living selling rhododendrons, azaleas,magnolias, Virginia creepers, asters, and other colonial exotica to a delighted English gentry.
Huge sums could be made with the right finds. John Lyon, an amateur botanist, spent twohard and dangerous years collecting specimens, but cleared almost $200,000 in today’smoney for his efforts. Many, however, just did it for the love of botany. Nuttall gave most ofwhat he found to the Liverpool Botanic Gardens. Eventually he became director of Harvard’sBotanic Garden and author of the encyclopedicGenera of North American Plants (which henot only wrote but also largely typeset).
And that was just plants. There was also all the fauna of the new worlds—kangaroos, kiwis,raccoons, bobcats, mosquitoes, and other curious forms beyond imagining. The volume of lifeon Earth was seemingly infinite, as Jonathan Swift noted in some famous lines:
So, naturalists observe, a fleaHath smaller fleas that on him prey;And these have smaller still to bite ’em;And so proceed ad infinitum.
All this new information needed to be filed, ordered, and compared with what was known.
The world was desperate for a workable system of classification. Fortunately there was a manin Sweden who stood ready to provide it.
His name was Carl Linné (later changed, with permission, to the more aristocraticvonLinné), but he is remembered now by the Latinized form Carolus Linnaeus. He was born in1707 in the village of R?shult in southern Sweden, the son of a poor but ambitious Lutherancurate, and was such a sluggish student that his exasperated father apprenticed him (or, by some accounts, nearly apprenticed him) to a cobbler. Appalled at the prospect of spending alifetime banging tacks into leather, young Linné begged for another chance, which wasgranted, and he never thereafter wavered from academic distinction. He studied medicine inSweden and Holland, though his passion became the natural world. In the early 1730s, still inhis twenties, he began to produce catalogues of the world’s plant and animal species, using asystem of his own devising, and gradually his fame grew.
Rarely has a man been more comfortable with his own greatness. He spent much of hisleisure time penning long and flattering portraits of himself, declaring that there had never“been a greater botanist or zoologist,” and that his system of classification was “the greatestachievement in the realm of science.” Modestly he suggested that his gravestone should bearthe inscription Princeps Botanicorum, “Prince of Botanists.” It was never wise to question hisgenerous self-assessments. Those who did so were apt to find they had weeds named afterthem.
Linnaeus’s other striking quality was an abiding—at times, one might say, a feverish—preoccupation with sex. He was particularly struck by the similarity between certain bivalvesand the female pudenda. To the parts of one species of clam he gave the names vulva, labia,pubes, anus, and hymen. He grouped plants by the nature of their reproductive organs andendowed them with an arrestingly anthropomorphic amorousness. His descriptions of flowersand their behavior are full of 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, adornedwith such noble bed curtains, and perfumed with so many soft scents that thebridegroom with his bride might there celebrate their nuptials with so much thegreater solemnity. When the bed has thus been made ready, then is the time for thebridegroom 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 namesthat were expansively descriptive. The common ground cherry was called Physalis amnoramosissime ramis angulosis glabris foliis dentoserratis. Linnaeus lopped it back to Physalisangulata, which name it still uses. The plant world was equally disordered by inconsistenciesof naming. A botanist could not be sure ifRosa sylvestris alba cum rubore, folio glabro wasthe same plant that others called Rosa sylvestris inodora seu canina. Linnaeus solved thepuzzlement by calling it simply Rosa canina. To make these excisions useful and agreeable toall 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, 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’s work to rectify this deficiency by classifying all that was alive according toits physical attributes. Taxonomy—which is to say the science of classification—has 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—the last that Linnaeuswould live to see—it 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 comprehensive—John Ray’s three-volume Historia Generalis Plantarum in England, completed a generationearlier, covered no fewer than 18,625 species of plants alone—but what Linnaeus had that noone else could touch were consistency, order, simplicity, and timeliness. Though his workdates from the 1730s, it didn’t become 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 “monstrous humans”
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, “man with a tail.” But 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’s lapses were offset by sound and oftenbrilliant taxonomy. Among other accomplishments, he saw that whales belonged with cows,mice, and other common 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—Convolvulus 1, Convolvulus 2,and so on—but 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—rocks, 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 thecommon names of many plants and animals had been heartily vulgar. The dandelion was longpopularly known as the “pissabed” because of its supposed diuretic properties, and othernames in everyday use included mare’s fart, naked ladies, twitch-ballock, hound’s piss, openarse, and bum-towel. One or two of these earthy appellations may unwittingly survive inEnglish yet. The “maidenhair” in maidenhair moss, for instance, does not refer to the hair onthe maiden’s 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 common 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’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 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 “vermes,” or worms, for everything that didn’t 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 Société 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 compromise and adopt a universal code.
Taxonomy is described sometimes as a science and sometimes as an art, but really it’s 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 “penis worms”). Familiar 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—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 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’t 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 commonduplications. 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 common 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 common chrysanthemum wasbanished (on apparently sound scientific principles) from the genus of the same name andrelegated to the comparatively drab and undesirable world of the genus Dendranthema.
Chrysanthemum breeders are a proud and numerous lot, and they protested to the real ifimprobable-sounding Committee on Spermatophyta. (There are also committees forPteridophyta, Bryophyta, and Fungi, among others, all reporting to an executive called theRapporteur-Général; this is truly an institution to cherish.) Although the rules of nomenclatureare supposed to be rigidly applied, botanists are not indifferent to sentiment, and in 1995 thedecision was reversed. Similar adjudications have saved petunias, euonymus, and a popularspecies of amaryllis from demotion, but not many species of geraniums, which some yearsago were transferred, amid howls, to the genus Pelargonium. The disputes are entertaininglysurveyed in Charles Elliott’s The Potting-Shed Papers.
Disputes and reorderings of much the same type can be found in all the other realms of theliving, so keeping an overall tally is not nearly as straightforward a matter as you mightsuppose. In consequence, the rather amazing fact is that we don’t have the faintest idea—“noteven to the nearest order of magnitude,” in the words of Edward O. Wilson—of the number ofthings that live on our planet. Estimates range from 3 million to 200 million. Moreextraordinary still, according to a report in the Economist, as much as 97 percent of theworld’s plant and animal species may still await discovery.
Of the organisms that we do know about, more than 99 in 100 are only sketchilydescribed—“a scientific name, a handful of specimens in a museum, and a few scraps ofdescription in scientific journals” is how Wilson describes the state of our knowledge. In TheDiversity of Life, he estimated the number of known species of all types—plants, insects,microbes, algae, everything—at 1.4 million, but added that that was just a guess. Otherauthorities have put the number of known species slightly higher, at around 1.5 million to 1.8million, but there is no central registry of these things, so nowhere to check numbers. In short,the remarkable position we find ourselves in is that we don’t actually know what we actuallyknow.
In principle you ought to be able to go to experts in each area of specialization, ask howmany species there are in their fields, then add the totals. Many people have in fact done so.
The problem is that seldom do any two come up with matching figures. Some sources put thenumber of known types of fungi at 70,000, others at 100,000—nearly half as many again. Youcan find confident assertions that the number of described earthworm species is 4,000 andequally confident assertions that the figure is 12,000. For insects, the numbers run from750,000 to 950,000 species. These are, you understand, supposedly the known number ofspecies. For plants, the commonly accepted numbers range from 248,000 to 265,000. Thatmay not seem too vast a discrepancy, but it’s more than twenty times the number of floweringplants in the whole of North America.
Putting things in order is not the easiest of tasks. In the early 1960s, Colin Groves of theAustralian National University began a systematic survey of the 250-plus known species ofprimate. Oftentimes it turned out that the same species had been described more than once— sometimes several times—without any of the discoverers realizing that they were dealing withan animal that was already known to science. It took Groves four decades to untangleeverything, and that was with a comparatively small group of easily distinguished, generallynoncontroversial creatures. Goodness knows what the results would be if anyone attempted asimilar exercise with the planet’s estimated 20,000 types of lichens, 50,000 species ofmollusk, or 400,000-plus beetles.
What is certain is that there is a great deal of life out there, though the actual quantities arenecessarily estimates based on extrapolations—sometimes exceedingly expansiveextrapolations. In a well-known exercise in the 1980s, Terry Erwin of the SmithsonianInstitution saturated a stand of nineteen rain forest trees in Panama with an insecticide fog,then collected everything that fell into his nets from the canopy. Among his haul (actuallyhauls, since he repeated the experiment seasonally to make sure he caught migrant species)were 1,200 types of beetle. Based on the distribution of beetles elsewhere, the number ofother tree species in the forest, the number of forests in the world, the number of other insecttypes, and so on up a long chain of variables, he estimated a figure of 30 million species ofinsects for the entire planet—a figure he later said was too conservative. Others using thesame or similar data have come up with figures of 13 million, 80 million, or 100 millioninsect types, underlining the conclusion that however carefully arrived at, such figuresinevitably owe at least as much to supposition as to science.
According to the Wall Street Journal, the world has “about 10,000 active taxonomists”—not a great number when you consider how much there is to be recorded. But, the Journaladds, because of the cost (about $2,000 per species) and paperwork, only about fifteenthousand new species of all types are logged per year.
“It’s not a biodiversity crisis, it’s a taxonomist crisis!” barks Koen Maes, Belgian-bornhead of invertebrates at the Kenyan National Museum in Nairobi, whom I met briefly on avisit to the country in the autumn of 2002. There were no specialized taxonomists in thewhole of Africa, he told me. “There was one in the Ivory Coast, but I think he has retired,” hesaid. It takes eight to ten years to train a taxonomist, but none are coming along in Africa.
“They are the real fossils,” Maes added. He himself was to be let go at the end of the year, hesaid. After seven years in Kenya, his contract was not being renewed. “No funds,” Maesexplained.
Writing in the journal Nature last year, the British biologist G. H. Godfray noted that thereis a chronic “lack of prestige and resources” for taxonomists everywhere. In consequence,“many species are being described poorly in isolated publications, with no attempt to relate anew taxon2to existing species and classifications.” Moreover, much of taxonomists’ time istaken up not with describing new species but simply with sorting out old ones. Many,according to Godfray, “spend most of their career trying to interpret the work of nineteenth-century systematicists: deconstructing their often inadequate published descriptions orscouring the world’s museums for type material that is often in very poor condition.” Godfrayparticularly stresses the absence of attention being paid to the systematizing possibilities ofthe Internet. The fact is that taxonomy by and large is still quaintly wedded to paper.
2The formal word for a zoological category, such as phylum or genus. The plural is taxa.
In an attempt to haul things into the modern age, in 2001 Kevin Kelly, cofounder of Wiredmagazine, launched an enterprise called the All Species Foundation with the aim of findingevery living organism and recording it on a database. The cost of such an exercise has beenestimated at anywhere from $2 billion to as much as $50 billion. As of the spring of 2002, thefoundation had just $1.2 million in funds and four full-time employees. If, as the numberssuggest, we have perhaps 100 million species of insects yet to find, and if our rates ofdiscovery continue at the present pace, we should have a definitive total for insects in a littleover fifteen thousand years. The rest of the animal kingdom may take a little longer.
So why do we know as little as we do? There are nearly as many reasons as there areanimals left to count, but here are a few of the principal causes:
Most living things are small and easily overlooked.In practical terms, this is not always abad thing. You might not slumber quite so contentedly if you were aware that your mattress ishome to perhaps two million microscopic mites, which come out in the wee hours to sup onyour sebaceous oils and feast on all those lovely, crunchy flakes of skin that you shed as youdoze and toss. Your pillow alone may be home to forty thousand of them. (To them your headis just one large oily bon-bon.) And don’t think a clean pillowcase will make a difference. Tosomething on the scale of bed mites, the weave of the tightest human fabric looks like ship’srigging. Indeed, if your pillow is six years old—which is apparently about the average age fora pillow—it has been estimated that one-tenth of its weight will be made up of “sloughedskin, living mites, dead mites and mite dung,” to quote the man who did the measuring, Dr.
John Maunder of the British Medical Entomology Center. (But at least they areyour mites.
Think of what you snuggle up with each time you climb into a motel bed.)3These mites havebeen with us since time immemorial, but they weren’t discovered until 1965.
If creatures as intimately associated with us as bed mites escaped our notice until the age ofcolor television, it’s hardly surprising that most of the rest of the small-scale world is barelyknown to us. Go out into a woods—any woods at all—bend down and scoop up a handful ofsoil, and you will be holding up to 10 billion bacteria, most of them unknown to science. Yoursample will also contain perhaps a million plump yeasts, some 200,000 hairy little fungiknown as molds, perhaps 10,000 protozoans (of which the most familiar is the amoeba), andassorted rotifers, flatworms, roundworms, and other microscopic creatures known collectivelyas cryptozoa. A large portion of these will also be unknown.
The most comprehensive handbook of microorganisms, Bergey’s Manual of SystematicBacteriology, lists about 4,000 types of bacteria. In the 1980s, a pair of Norwegian scientists,Jostein Goks?yr and Vigdis Torsvik, collected a gram of random soil from a beech forest neartheir lab in Bergen and carefully analyzed its bacterial content. They found that this singlesmall sample contained between 4,000 and 5,000 separate bacterial species, more than in thewhole of Bergey’s Manual. They then traveled to a coastal location a few miles away,scooped up another gram of earth, and found that it contained 4,000 to 5,000 other species. AsEdward O. Wilson observes: “If over 9,000 microbial types exist in two pinches of substratefrom two localities in Norway, how many more await discovery in other, radically differenthabitats?” Well, according to one estimate, it could be as high as 400 million.
3We are actually getting worse at some matters of hygiene. Dr. Maunder believes that the move toward low-temperature washing machine detergents has encouraged bugs to proliferate. As he puts it: "If you wash lousyclothing at low temperatures, all you get is cleaner lice." We don’t look in the right places. In The Diversity of Life, Wilson describes how onebotanist spent a few days tramping around ten hectares of jungle in Borneo and discovered athousand new species of flowering plant—more than are found in the whole of NorthAmerica. The plants weren’t hard to find. It’s just that no one had looked there before. KoenMaes of the Kenyan National Museum told me that he went to one cloud forest, asmountaintop forests are known in Kenya, and in a half hour “of not particularly dedicatedlooking” found four new species of millipedes, three representing new genera, and one newspecies of tree. “Big tree,” he added, and shaped his arms as if about to dance with a verylarge partner. Cloud forests are found on the tops of plateaus and have sometimes beenisolated for millions of years. “They provide the ideal climate for biology and they havehardly been studied,” he said.
Overall, tropical rain forests cover only about 6 percent of Earth’s surface, but harbor morethan half of its animal life and about two-thirds of its flowering plants, and most of this liferemains unknown to us because too few researchers spend time in them. Not incidentally,much of this could be quite valuable. At least 99 percent of flowering plants have never beentested for their medicinal properties. Because they can’t flee from predators, plants have hadto contrive chemical defenses, and so are particularly enriched in intriguing compounds. Evennow nearly a quarter of all prescribed medicines are derived from just forty plants, withanother 16 percent coming from animals or microbes, so there is a serious risk with everyhectare of forest felled of losing medically vital possibilities. Using a method calledcombinatorial chemistry, chemists can generate forty thousand compounds at a time in labs,but these products are random and not uncommonly useless, whereas any natural moleculewill have already passed what the Economist calls “the ultimate screening programme: overthree and a half billion years of evolution.”
Looking for the unknown isn’t simply a matter of traveling to remote or distant places,however. In his book Life: An Unauthorised Biography, Richard Fortey notes how oneancient bacterium was found on the wall of a country pub “where men had urinated forgenerations”—a discovery that would seem to involve rare amounts of luckand devotion andpossibly some other quality not specified.
There aren’t enough specialists.The stock of things to be found, examined, and recordedvery much outruns the supply of scientists available to do it. Take the hardy and little-knownorganisms known as bdelloid rotifers. These are microscopic animals that can survive almostanything. When conditions are tough, they curl up into a compact shape, switch off theirmetabolism, and wait for better times. In this state, you can drop them into boiling water orfreeze them almost to absolute zero—that is the level where even atoms give up—and, whenthis torment has finished and they are returned to a more pleasing environment, they willuncurl and move on as if nothing has happened. So far, about 500 species have been identified(though other sources say 360), but nobody has any idea, even remotely, how many there maybe altogether. For years almost all that was known about them was thanks to the work of adevoted amateur, a London clerical worker named David Bryce who studied them in his sparetime. They can be found all over the world, but you could have all the bdelloid rotifer expertsin the world to dinner and not have to borrow plates from the neighbors.
Even something as important and ubiquitous as fungi—and fungi are both—attractscomparatively little notice. Fungi are everywhere and come in many forms—as mushrooms,molds, mildews, yeasts, and puffballs, to name but a sampling—and they exist in volumes that most of us little suspect. Gather together all the fungi found in a typical acre of meadowand you would have 2,500 pounds of the stuff. These are not marginal organisms. Withoutfungi there would be no potato blights, Dutch elm disease, jock itch, or athlete’s foot, but alsono yogurts or beers or cheeses. Altogether about 70,000 species of fungi have been identified,but it is thought the number could be as high as 1.8 million. A lot of mycologists work inindustry, making cheeses and yogurts and the like, so it is hard to say how many are activelyinvolved in research, but we can safely take it that there are more species of fungi to be foundthan there are people to find them.
The world is a really big place.We have been gulled by the ease of air travel and otherforms of communication into thinking that the world is not all that big, but at ground level,where researchers must work, it is actually enormous—enormous enough to be full ofsurprises. The okapi, the nearest living relative of the giraffe, is now known to exist insubstantial numbers in the rain forests of Zaire—the total population is estimated at perhapsthirty thousand—yet its existence wasn’t even suspected until the twentieth century. The largeflightless New Zealand bird called the takahe had been presumed extinct for two hundredyears before being found living in a rugged area of the country’s South Island. In 1995 a teamof French and British scientists in Tibet, who were lost in a snowstorm in a remote valley,came across a breed of horse, called the Riwoche, that had previously been known only fromprehistoric cave drawings. The valley’s inhabitants were astonished to learn that the horse wasconsidered a rarity in the wider world.
Some people think even greater surprises may await us. “A leading British ethno-biologist,” wrote the Economist in 1995, “thinks a megatherium, a sort of giant ground slothwhich may stand as high as a giraffe . . . may lurk in the fastnesses of the Amazon basin.”
Perhaps significantly, the ethnobiologist wasn’t named; perhaps even more significantly,nothing more has been heard of him or his giant sloth. No one, however, can categorically saythat no such thing is there until every jungly glade has been investigated, and we are a longway from achieving that.
But even if we groomed thousands of fieldworkers and dispatched them to the farthestcorners of the world, it would not be effort enough, for wherever life can be, it is. Life’sextraordinary fecundity is amazing, even gratifying, but also problematic. To survey it all, youwould have to turn over every rock, sift through the litter on every forest floor, sieveunimaginable quantities of sand and dirt, climb into every forest canopy, and devise muchmore efficient ways to examine the seas. Even then you would overlook whole ecosystems. Inthe 1980s, spelunkers entered a deep cave in Romania that had been sealed off from theoutside world for a long but unknown period and found thirty-three species of insects andother small creatures—spiders, centipedes, lice—all blind, colorless, and new to science.
They were living off the microbes in the surface scum of pools, which in turn were feeding onhydrogen sulfide from hot springs.
Our instinct may be to see the impossibility of tracking everything down as frustrating,dispiriting, perhaps even appalling, but it can just as well be viewed as almost unbearablyexciting. We live on a planet that has a more or less infinite capacity to surprise. Whatreasoning person could possibly want it any other way?
What is nearly always most arresting in any ramble through the scattered disciplines ofmodern science is realizing how many people have been willing to devote lifetimes to the most sumptuously esoteric lines of inquiry. In one of his essays, Stephen Jay Gould notes howa hero of his named Henry Edward Crampton spent fifty years, from 1906 to his death in1956, quietly studying a genus of land snails in Polynesia called Partula. Over and over, yearafter year, Crampton measured to the tiniest degree—to eight decimal places—the whorls andarcs and gentle curves of numberless Partula, compiling the results into fastidiously detailedtables. A single line of text in a Crampton table could represent weeks of measurement andcalculation.
Only slightly less devoted, and certainly more unexpected, was Alfred C. Kinsey, whobecame famous for his studies of human sexuality in the 1940s and 1950s. But before hismind became filled with sex, so to speak, Kinsey was an entomologist, and a dogged one atthat. In one expedition lasting two years, he hiked 2,500 miles to assemble a collection of300,000 wasps. How many stings he collected along the way is not, alas, recorded.
Something that had been puzzling me was the question of how you assured a chain ofsuccession in these arcane fields. Clearly there cannot be many institutions in the world thatrequire or are prepared to support specialists in barnacles or Pacific snails. As we parted at theNatural History Museum in London, I asked Richard Fortey how science ensures that whenone person goes there’s someone ready to take his place.
He chuckled rather heartily at my naiveté. “I’m afraid it’s not as if we have substitutessitting on the bench somewhere waiting to be called in to play. When a specialist retires or,even more unfortunately, dies, that can bring a stop to things in that field, sometimes for avery long while.”
“And I suppose that’s why you value someone who spends forty-two years studying