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 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 “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 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—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—attractsparatively little notice。 fungi are everywhere and e 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 munication 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； piling 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 asingle species of plant； even if it doesn’t produce anything terribly new？”
“precisely；” he said； “precisely。” and he really seemed to mean it。
。。。！
24CELLS
^生。网！
it starts with a single cell。 the first cell splits to bee two and the two bee fourand so on。 after just forty…seven doublings； you have ten thousand trillion（10；000；000；000；000；000） cells in your body and are ready to spring forth as a human being。
1and every one of those cel