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cident of nature as a product of orderly development。鈥�
but the real heat directed at gould arose from the belief that many of his conclusions weresimply mistaken or carelessly inflated。 writing in the journal evolution； dawkins attackedgould鈥檚 assertions that 鈥渆volution in the cambrian was a different kind of process fromtoday鈥潯nd expressed exasperation at gould鈥檚 repeated suggestions that 鈥渢he cambrian was aperiod of evolutionary 鈥榚xperiment；鈥櫋volutionary 鈥榯rial and error；鈥櫋volutionary 鈥榝alse starts。鈥櫋 �
。 。 it was the fertile time when all the great 鈥榝undamental body plans鈥櫋ere invented。
nowadays； evolution just tinkers with old body plans。 back in the cambrian； new phyla andnew classes arose。 nowadays we only get new species！鈥�
noting how often this idea鈥攖hat there are no new body plans鈥攊s picked up； dawkins says：
鈥渋t is as though a gardener looked at an oak tree and remarked； wonderingly： 鈥榠sn鈥檛 it strangethat no major new boughs have appeared on this tree for many years？ these days； all the newgrowth appears to be at the twig level。鈥櫋♀��
鈥渋t was a strange time；鈥潯ortey says now； 鈥渆specially when you reflected that this was allabout something that happened five hundred million years ago； but feelings really did runquite high。 i joked in one of my books that i felt as if i ought to put a safety helmet on beforewriting about the cambrian period； but it did actually feel a bit like that。鈥�
strangest of all was the response of one of the heroes of wonderful life； simon conwaymorris； who startled many in the paleontological munity by rounding abruptly on gouldin a book of his own； the crucible of creation。 the book treated gould 鈥渨ith contempt； evenloathing；鈥潯n fortey鈥檚 words。 鈥渋 have never encountered such spleen in a book by aprofessional；鈥潯ortey wrote later。 鈥渢he casual reader of the crucible of creation； unaware of the history； would never gather that the author鈥檚 views had once been close to （if not actuallyshared with） gould鈥檚。鈥�
when i asked fortey about it； he said： 鈥渨ell； it was very strange； quite shocking really；because gould鈥檚 portrayal of him had been so flattering。 i could only assume that simon wasembarrassed。 you know； science changes but books are permanent； and i suppose he regrettedbeing so irremediably associated with views that he no longer altogether held。 there was allthat stuff about 鈥榦h fuck； another phylum鈥櫋nd i expect he regretted being famous for that。鈥�
what happened was that the early cambrian fossils began to undergo a period of criticalreappraisal。 fortey and derek briggs鈥攐ne of the other principals in gould鈥檚 book鈥攗sed amethod known as cladistics to pare the various burgess fossils。 in simple terms； cladisticsconsists of organizing organisms on the basis of shared features。 fortey gives as an examplethe idea of paring a shrew and an elephant。 if you considered the elephant鈥檚 large size andstriking trunk you might conclude that it could have little in mon with a tiny； sniffingshrew。 but if you pared both of them with a lizard； you would see that the elephant andshrew were in fact built to much the same plan。 in essence； what fortey is saying is thatgould saw elephants and shrews where they saw mammals。 the burgess creatures； theybelieved； weren鈥檛 as strange and various as they appeared at first sight。 鈥渢hey were often nostranger than trilobites；鈥潯ortey says now。 鈥渋t is just that we have had a century or so to getused to trilobites。 familiarity； you know； breeds familiarity。鈥�
this wasn鈥檛； i should note； because of sloppiness or inattention。 interpreting the forms andrelationships of ancient animals on the basis of often distorted and fragmentary evidence isclearly a tricky business。 edward o。 wilson has noted that if you took selected species ofmodern insects and presented them as burgess…style fossils nobody would ever guess that theywere all from the same phylum； so different are their body plans。 also instrumental in helpingrevisions were the discoveries of two further early cambrian sites； one in greenland and onein china； plus more scattered finds； which between them yielded many additional and oftenbetter specimens。
the upshot is that the burgess fossils were found to be not so different after all。
hallucigenia； it turned out； had been reconstructed upside down。 its stilt…like legs wereactually spikes along its back。 peytoia； the weird creature that looked like a pineapple slice；was found to be not a distinct creature but merely part of a larger animal called anomalocaris。
many of the burgess specimens have now been assigned to living phyla鈥攋ust where walcottput them in the first place。 hallucigenia and some others are thought to be related toonychophora； a group of caterpillar…like animals。 others have been reclassified as precursorsof the modern annelids。 in fact； says fortey； 鈥渢here are relatively few cambrian designs thatare wholly novel。 more often they turn out to be just interesting elaborations of well…established designs。鈥潯s he wrote in his book life： 鈥渘one was as strange as a present daybarnacle； nor as grotesque as a queen termite。鈥�
so the burgess shale specimens weren鈥檛 so spectacular after all。 this made them； as forteyhas written； 鈥渘o less interesting； or odd； just more explicable。鈥潯heir weird body plans werejust a kind of youthful exuberance鈥攖he evolutionary equivalent； as it were； of spiked hair andtongue studs。 eventually the forms settled into a staid and stable middle age。
but that still left the enduring question of where all these animals had e from鈥攈owthey had suddenly appeared from out of nowhere。
alas； it turns out the cambrian explosion may not have been quite so explosive as all that。
the cambrian animals； it is now thought； were probably there all along； but were just toosmall to see。 once again it was trilobites that provided the clue鈥攊n particular that seeminglymystifying appearance of different types of trilobite in widely scattered locations around theglobe； all at more or less the same time。
on the face of it； the sudden appearance of lots of fully formed but varied creatures wouldseem to enhance the miraculousness of the cambrian outburst； but in fact it did the opposite。
it is one thing to have one well…formed creature like a trilobite burst forth in isolation鈥攖hatreally is a wonder鈥攂ut to have many of them； all distinct but clearly related； turning upsimultaneously in the fossil record in places as far apart as china and new york clearlysuggests that we are missing a big part of their history。 there could be no stronger evidencethat they simply had to have a forebear鈥攕ome grandfather species that started the line in amuch earlier past。
and the reason we haven鈥檛 found these earlier species； it is now thought； is that they weretoo tiny to be preserved。 says fortey： 鈥渋t isn鈥檛 necessary to be big to be a perfectlyfunctioning； plex organism。 the sea swarms with tiny arthropods today that have left nofossil record。鈥潯e cites the little copepod； which numbers in the trillions in modern seas andclusters in shoals large enough to turn vast areas of the ocean black； and yet our totalknowledge of its ancestry is a single specimen found in the body of an ancient fossilized fish。
鈥渢he cambrian explosion； if that鈥檚 the word for it； probably was more an increase in sizethan a sudden appearance of new body types；鈥潯ortey says。 鈥渁nd it could have happened quiteswiftly； so in that sense i suppose it was an explosion。鈥潯he idea is that just as mammalsbided their time for a hundred million years until the dinosaurs cleared off and then seeminglyburst forth in profusion all over the planet； so too perhaps the arthropods and other triploblastswaited in semimicroscopic anonymity for the dominant ediacaran organisms to have theirday。 says fortey： 鈥渨e know that mammals increased in size quite dramatically after thedinosaurs went鈥攖hough when i say quite abruptly i of course mean it in a geological sense。
we鈥檙e still talking millions of years。鈥�
incidentally； reginald sprigg did eventually get a measure of overdue credit。 one of themain early genera； spriggina； was named