按键盘上方向键 ← 或 → 可快速上下翻页，按键盘上的 Enter 键可回到本书目录页，按键盘上方向键 ↑ 可回到本页顶部！
————未阅读完？加入书签已便下次继续阅读！
ing 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 prehensive handbook of microorganisms； bergey鈥檚 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鈥檚 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： 鈥渋f over 9；000 microbial types exist in two pinches of substratefrom two localities in norway； how many more await discovery in other； radically differenthabitats？鈥潯ell； 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鈥檛 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鈥攎ore than are found in the whole of northamerica。 the plants weren鈥檛 hard to find。 it鈥檚 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 鈥渙f not particularly dedicatedlooking鈥潯ound four new species of millipedes； three representing new genera； and one newspecies of tree。 鈥渂ig tree；鈥潯e 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。 鈥渢hey provide the ideal climate for biology and they havehardly been studied；鈥潯e said。
overall； tropical rain forests cover only about 6 percent of earth鈥檚 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鈥檛 flee from predators； plants have hadto contrive chemical defenses； and so are particularly enriched in intriguing pounds。 evennow nearly a quarter of all prescribed medicines are derived from just forty plants； withanother 16 percent ing from animals or microbes； so there is a serious risk with everyhectare of forest felled of losing medically vital possibilities。 using a method calledbinatorial chemistry； chemists can generate forty thousand pounds at a time in labs；but these products are random and not unmonly useless； whereas any natural moleculewill have already passed what the economist calls 鈥渢he ultimate screening programme： overthree and a half billion years of evolution。鈥�
looking for the unknown isn鈥檛 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 鈥渨here men had urinated forgenerations鈥濃�攁 discovery that would seem to involve rare amounts of luckand devotion andpossibly some other quality not specified。
there aren鈥檛 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 pact 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鈥攖hat is the level where even atoms give up鈥攁nd； 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鈥攁nd fungi are both鈥攁ttractsparatively little notice。 fungi are everywhere and e in many forms鈥攁s mushrooms；molds； mildews； yeasts； and puffballs； to name but a sampling鈥攁nd 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鈥檚 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 munication into thinking that the world is not all that big； but at ground level；where researchers must work； it is actually enormous鈥攅normous 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鈥攖he total population is estimated at perhapsthirty thousand鈥攜et its existence wasn鈥檛 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鈥檚 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鈥檚 inhabitants were astonished to learn that the horse wasconsidered a rarity in the wider world。
some people think even greater surprises may await us。 鈥渁 leading british ethno…biologist；鈥潯rote the economist in 1995； 鈥渢hinks a megatherium； a sort of giant ground slothwhich may stand as high as a giraffe 。 。 。 may lurk in the fastnesses of the amazon basin。鈥�
perhaps significantly； the ethnobiologist wasn鈥檛 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鈥檚extraordinary 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鈥攕piders； centipedes； lice鈥攁ll 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