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than this； the earliest trilobites didn鈥檛 consist of just one venturesome speciesbut dozens； and didn鈥檛 appear in one or two locations but all over。 many thinking people inthe nineteenth century saw this as proof of god鈥檚 handiwork and refutation of darwin鈥檚evolutionary ideals。 if evolution proceeded slowly； they asked； then how did he account forthis sudden appearance of plex； fully formed creatures？ the fact is； he couldn鈥檛。
and so matters seemed destined to remain forever until one day in 1909； three months shyof the fiftieth anniversary of the publication of darwin鈥檚 on the origin of species ； when apaleontologist named charles doolittle walcott made an extraordinary find in the canadianrockies。
walcott was born in 1850 and grew up near utica； new york； in a family of modest means；which became more modest still with the sudden death of his father when walcott was aninfant。 as a boy walcott discovered that he had a knack for finding fossils； particularlytrilobites； and built up a collection of sufficient distinction that it was bought by louisagassiz for his museum at harvard for a small fortune鈥攁bout 70；000 in today鈥檚 money。
although he had barely a high school education and was self taught in the sciences； walcottbecame a leading authority on trilobites and was the first person to establish that trilobiteswere arthropods； the group that includes modern insects and crustaceans。
in 1879 he took a job as a field researcher with the newly formed united states geologicalsurvey and served with such distinction that within fifteen years he had risen to be its head。 in1907 he was appointed secretary of the smithsonian institution； where he remained until hisdeath in 1927。 despite his administrative obligations； he continued to do fieldwork and towrite prolifically。 鈥渉is books fill a library shelf；鈥潯ccording to fortey。 not incidentally； hewas also a founding director of the national advisory mittee for aeronautics； whicheventually became the national aeronautics and space agency； or nasa； and thus canrightly be considered the grandfather of the space age。
but what he is remembered for now is an astute but lucky find in british columbia； highabove the little town of field； in the late summer of 1909。 the customary version of the storyis that walcott； acpanied by his wife； was riding on horseback on a mountain trail beneaththe spot called the burgess ridge when his wife鈥檚 horse slipped on loose stones。 dismountingto assist her； walcott discovered that the horse had turned a slab of shale that contained fossilcrustaceans of an especially ancient and unusual type。 snow was falling鈥攚inter es earlyto the canadian rockies鈥攕o they didn鈥檛 linger； but the next year at the first opportunitywalcott returned to the spot。 tracing the presumed route of the rocks鈥櫋lide； he climbed 750feet to near the mountain鈥檚 summit。 there； 8；000 feet above sea level； he found a shaleoutcrop； about the length of a city block； containing an unrivaled array of fossils from soonafter the moment when plex life burst forth in dazzling profusion鈥攖he famous cambrianexplosion。 walcott had found； in effect； the holy grail of paleontology。 the outcrop becameknown as the burgess shale； and for a long time it provided 鈥渙ur sole vista upon the inceptionof modern life in all its fullness；鈥潯s the late stephen jay gould recorded in his popular bookwonderful life 。
gould； ever scrupulous； discovered from reading walcott鈥檚 diaries that the story of theburgess shale鈥檚 discovery appears to have been somewhat embroidered鈥攚alcott makes nomention of a slipping horse or falling snow鈥攂ut there is no disputing that it was anextraordinary find。
it is almost impossible for us whose time on earth is limited to a breezy few decades toappreciate how remote in time from us the cambrian outburst was。 if you could fly backwardsinto the past at the rate of one year per second； it would take you about half an hour to reachthe time of christ； and a little over three weeks to get back to the beginnings of human life。
but it would take you twenty years to reach the dawn of the cambrian period。 it was； in otherwords； an extremely long time ago； and the world was a very different place。
for one thing； 500…million…plus years ago when the burgess shale was formed it wasn鈥檛 atthe top of a mountain but at the foot of one。 specifically it was a shallow ocean basin at thebottom of a steep cliff。 the seas of that time teemed with life； but normally the animals left norecord because they were soft…bodied and decayed upon dying。 but at burgess the cliffcollapsed； and the creatures below； entombed in a mudslide； were pressed like flowers in abook； their features preserved in wondrous detail。
in annual summer trips from 1910 to 1925 （by which time he was seventy…five years old）；walcott excavated tens of thousands of specimens （gould says 80；000； the normallyunimpeachable fact checkers of national georgraphic say 60；000）； which he brought back towashington for further study。 in both sheer numbers and diversity the collection wasunparalleled。 some of the burgess fossils had shells； many others did not。 some were sighted；others blind。 the variety was enormous； consisting of 140 species by one count。 鈥渢he burgessshale included a range of disparity in anatomical designs never again equaled； and notmatched today by all the creatures in the world鈥檚 oceans；鈥潯ould wrote。
unfortunately； according to gould； walcott failed to discern the significance of what hehad found。 鈥渟natching defeat from the jaws of victory；鈥潯ould wrote in another work； eightlittle piggies； 鈥渨alcott then proceeded to misinterpret these magnificent fossils in the deepestpossible way。鈥潯e placed them into modern groups； making them ancestral to today鈥檚 worms；jellyfish； and other creatures； and thus failed to appreciate their distinctness。 鈥渦nder such aninterpretation；鈥潯ould sighed； 鈥渓ife began in primordial simplicity and moved inexorably；predictably onward to more and better。鈥�
walcott died in 1927 and the burgess fossils were largely forgotten。 for nearly half acentury they stayed shut away in drawers in the american museum of natural history inwashington； seldom consulted and never questioned。 then in 1973 a graduate student fromcambridge university named simon conway morris paid a visit to the collection。 he wasastonished by what he found。 the fossils were far more varied and magnificent than walcotthad indicated in his writings。 in taxonomy the category that describes the basic body plans ofall organisms is the phylum； and here； conway morris concluded； were drawer after drawer ofsuch anatomical singularities鈥攁ll amazingly and unaccountably unrecognized by the manwho had found them。
with his supervisor； harry whittington； and fellow graduate student derek briggs； conwaymorris spent the next several years making a systematic revision of the entire collection； andcranking out one exciting monograph after another as discovery piled upon discovery。 manyof the creatures employed body plans that were not simply unlike anything seen before orsince； but were bizarrely different。 one； opabinia； had five eyes and a nozzle…like snout withclaws on the end。 another； a disc…shaped being called peytoia； looked almost ically like apineapple slice。 a third had evidently tottered about on rows of stilt…like legs； and was so oddthat they named it hallucigenia。 there was so much unrecognized novelty in the collectionthat at one point upon opening a new drawer conway morris famously was heard to mutter；鈥渙h fuck； not another phylum。鈥�
the english team鈥檚 revisions showed that the cambrian had been a time of unparalleledinnovation and experimentation in body designs。 for almost four billion years life haddawdled along without any detectable ambitions in the direction of plexity； and thensuddenly； in the space of just five or ten million years； it had created all the basic bodydesigns still in use today。 name a creature； from a nematode worm to cameron diaz； and theyall use architecture first created in the cambrian party。
what was most surprising； however； was that there were so many body designs that hadfailed to make the cut； so to speak； and left n