万物简史英文版_比尔·布莱森- 第85节

what　was　most　surprising；　however；　was　that　there　were　so　many　body　designs　that　hadfailed　to　make　the　cut；　so　to　speak；　and　left　no　descendants。　altogether；　according　to　gould；　atleast　fifteen　and　perhaps　as　many　as　twenty　of　the　burgess　animals　belonged　to　no　recognizedphylum。　（the　number　soon　grew　in　some　popular　accounts　to　as　many　as　one　hundred鈥攆armore　than　the　cambridge　scientists　ever　actually　claimed。）　鈥渢he　history　of　life；鈥潯�wrote　gould；鈥渋s　a　story　of　massive　removal　followed　by　differentiation　within　a　few　surviving　stocks；　notthe　conventional　tale　of　steadily　increasing　excellence；　plexity；　and　diversity。鈥�

evolutionary　success；　it　appeared；　was　a　lottery。

one　creature　thatdid　manage　to　slip　through；　a　small　wormlike　being　called　pikaiagracilens；　was　found　to　have　a　primitive　spinal　column；　making　it　the　earliest　known　ancestorof　all　later　vertebrates；　including　us。pikaia　were　by　no　means　abundant　among　the　burgessfossils；　so　goodness　knows　how　close　they　may　have　e　to　extinction。　gould；　in　a　famousquotation；　leaves　no　doubt　that　he　sees　our　lineal　success　as　a　fortunate　fluke：　鈥渨ind　back　thetape　of　life　to　the　early　days　of　the　burgess　shale；　let　it　play　again　from　an　identical　startingpoint；　and　the　chance　bees　vanishingly　small　that　anything　like　human　intelligence　wouldgrace　the　replay。鈥�

gould鈥檚　book　was　published　in　1989　to　general　critical　acclaim　and　was　a　great　mercialsuccess。　what　wasn鈥檛　generally　known　was　that　many　scientists　didn鈥檛　agree　with　gould鈥檚conclusions　at　all；　and　that　it　was　all　soon　to　get　very　ugly。　in　the　context　of　the　cambrian；鈥渆xplosion鈥潯�would　soon　have　more　to　do　with　modern　tempers　than　ancient　physiologicalfacts。

in　fact；　we　now　know；　plex　organisms　existed　at　least　a　hundred　million　years　beforethe　cambrian。　we　should　have　known　a　whole　lot　sooner。　nearly　forty　years　after　walcottmade　his　discovery　in　canada；　on　the　other　side　of　the　planet　in　australia；　a　young　geologistnamed　reginald　sprigg　found　something　even　older　and　in　its　way　just　as　remarkable。

in　1946　sprigg　was　a　young　assistant　government　geologist　for　the　state　of　south　australiawhen　he　was　sent　to　make　a　survey　of　abandoned　mines　in　the　ediacaran　hills　of　the　flindersrange；　an　expanse　of　baking　outback　some　three　hundred　miles　north　of　adelaide。　the　ideawas　to　see　if　there　were　any　old　mines　that　might　be　profitably　reworked　using　newertechnologies；　so　he　wasn鈥檛　studying　surface　rocks　at　all；　still　less　fossils。　but　one　day　whileeating　his　lunch；　sprigg　idly　overturned　a　hunk　of　sandstone　and　was　surprised鈥攖o　put　itmildly鈥攖o　see　that　the　rock鈥檚　surface　was　covered　in　delicate　fossils；　rather　like　theimpressions　leaves　make　in　mud。　these　rocks　predated　the　cambrian　explosion。　he　waslooking　at　the　dawn　of　visible　life。

sprigg　submitted　a　paper　to　nature　；　but　it　was　turned　down。　he　read　it　instead　at　the　nextannual　meeting　of　the　australian　and　new　zealand　association　for　the　advancement　ofscience；　but　it　failed　to　find　favor　with　the　association鈥檚　head；　who　said　the　ediacaranimprints　were　merely　鈥渇ortuitous　inorganic　markings鈥濃�攑atterns　made　by　wind　or　rain　ortides；　but　not　living　beings。　his　hopes　not　yet　entirely　crushed；　sprigg　traveled　to　london　andpresented　his　findings　to　the　1948　international　geological　congress；　but　failed　to　exciteeither　interest　or　belief。　finally；　for　want　of　a　better　outlet；　he　published　his　findings　in　thetransactions　of　the　royal　society　of　south　australia。　then　he　quit　his　government　job　andtook　up　oil　exploration。

nine　　years　　later；　　in　　1957；　　a　　schoolboy　　named　john　mason；　while　walking　throughcharnwood　forest　in　the　english　midlands；　found　a　rock　with　a　strange　fossil　in　it；　similar　toa　modern　sea　pen　and　exactly　like　some　of　the　specimens　sprigg　had　found　and　been　trying　totell　everyone　about　ever　since。　the　schoolboy　turned　it　in　to　a　paleontologist　at　the　universityof　leicester；　who　identified　it　at　once　as　precambrian。　young　mason　got　his　picture　in　thepapers　and　was　treated　as　a　precocious　hero；　he　still　is　in　many　books。　the　specimen　wasnamed　in　his　honor　chamia　masoni。

today　some　of　sprigg鈥檚　original　ediacaran　specimens；　along　with　many　of　the　other　fifteenhundred　specimens　that　have　been　found　throughout　the　flinders　range　since　that　time；　canbe　seen　in　a　glass　case　in　an　upstairs　room　of　the　stout　and　lovely　south　australian　museumin　adelaide；　but　they　don鈥檛　attract　a　great　deal　of　attention。　the　delicately　etched　patterns　arerather　faint　and　not　terribly　arresting　to　the　untrained　eye。　they　are　mostly　small　and　disc…shaped；　with　occasional；　vague　trailing　ribbons。　fortey　has　described　them　as　鈥渟oft…bodiedoddities。鈥�

there　is　still　very　little　agreement　about　what　these　things　were　or　how　they　lived。　theyhad；　as　far　as　can　be　told；　no　mouth　or　anus　with　which　to　take　in　and　discharge　digestivematerials；　and　no　internal　organs　with　which　to　process　them　along　the　way。　鈥渋n　life；鈥潯�forteysays；　鈥渕ost　of　them　probably　simply　lay　upon　the　surface　of　the　sandy　sediment；　like　soft；structureless　and　inanimate　flatfish。鈥潯�at　their　liveliest；　they　were　no　more　plex　thanjellyfish。　all　the　ediacaran　creatures　were　diploblastic；　meaning　they　were　built　from　twolayers　of　tissue。　with　the　exception　of　jellyfish；　all　animals　today　are　triploblastic。

some　experts　think　they　weren鈥檛　animals　at　all；　but　more　like　plants　or　fungi。　thedistinctions　between　plant　and　animal　are　not　always　clear　even　now。　the　modern　spongespends　its　life　fixed　to　a　single　spot　and　has　no　eyes　or　brain　or　beating　heart；　and　yet　is　ananimal。　鈥渨hen　we　go　back　to　the　precambrian　the　differences　between　plants　and　animalswere　probably　even　less　clear；鈥潯�says　fortey。　鈥渢here　isn鈥檛　any　rule　that　says　you　have　to　bedemonstrably　one　or　the　other。鈥�

nor　is　it　agreed　that　the　ediacaran　organisms　are　in　any　way　ancestral　to　anything　alivetoday　（except　possibly　some　jellyfish）。　many　authorities　see　them　as　a　kind　of　failedexperiment；　a　stab　at　plexity　that　didn鈥檛　take；　possibly　because　the　sluggish　ediacaranorganisms　were　devoured　or　outpeted　by　the　lither　and　more　sophisticated　animals　of　thecambrian　period。

鈥渢here　is　nothing　closely　similar　alive　today；鈥潯�fortey　has　written。　鈥渢hey　are　difficult　tointerpret　as　any　kind　of　ancestors　of　what　was　to　follow。鈥�

the　feeling　was　that　ultimately　they　weren鈥檛　terribly　important　to　the　development　of　lifeon　earth。　many　authorities　believe　that　there　was　a　mass　extermination　at　the　precambrian鈥揷ambrian　boundary　and　that　all　the　ediacaran　creatures　（except　the　uncertain　jellyfish）　failedto　move　on　to　the　next　phase。　the　real　business　of　plex　life；　in　other　words；　started　withthe　cambrian　explosion。　that鈥檚　how　gould　saw　it　in　any　case。

as　for　the　revisions　of　the　burgess　shale　fossils；　almost　at　once　people　began　to　questionthe　interpretations　and；　in　particular；　gould鈥檚　interpretation　of　the　interpretations。　鈥渇rom　thefirst　there　were　a　number　of　scientists　who　doubted　the　account　that　steve　gould　hadpresented；　however　much　they　admired　the　manner　of　its　delivery；鈥潯�fortey　wrote　in　life。　thatis　putting　it　mildly。

鈥渋f　only　stephen　gould　could　think　as　clearly　as　he　writes！鈥潯�barked　the　oxford　academicrichard　dawkins　in　the　opening　line　of　a　review　（in　the　london　sunday　telegraph）　ofwonderful　life。　dawkins　acknowledged　that　the　book　was　鈥渦nputdownable鈥潯�and　a　鈥渓iterarytour…de…force；鈥潯�but　accused　gould　of　engaging　in　a　鈥済randiloquent　and　near…disingenuous鈥�

misrepresentation　of　the　facts　by　suggesting　that　the　burgess　revisions　had　stunned　thepaleontological　munity。　鈥渢he　view　that　he　is　attacking鈥攖hat　evolution　marchesinexorably　toward　a　pinnacle　such　as　man鈥攈as　not　been　believed　for　50　years；鈥潯�dawkinsfumed。

and　yet　that　was　exactly　the　conclusion　to　which　many　general　reviewers　were　drawn。

one；　writing　in　the　new　york　times　book　review；　cheerfully　suggested　that　as　a　result　ofgould鈥檚　book　scientists　鈥渉ave　been　throwing　out　some　preconceptions　that　they　had　notexamined　for　generations。　they　are；　reluctantly　or　enthusiastically；　accepting　the　idea　thathumans　are　as　much　an　accident　of　nature　as　a　product　of　orderly　development。鈥�

but　the