《A Short History of Nearly Everything》第119章

。　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　prehensive　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　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