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ed withthe cambrian explosion。 that’s 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’s interpretation of the interpretations。 “from thefirst there were a number of scientists who doubted the account that steve gould hadpresented； however much they admired the manner of its delivery；” fortey wrote in life。 thatis putting it mildly。
“if only stephen gould could think as clearly as he writes！” 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 “unputdownable” and a “literarytour…de…force；” but accused gould of engaging in a “grandiloquent and near…disingenuous”
misrepresentation of the facts by suggesting that the burgess revisions had stunned thepaleontological munity。 “the view that he is attacking—that evolution marchesinexorably toward a pinnacle such as man—has not been believed for 50 years；” 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’s book scientists “have 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。”
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’s assertions that “evolution in the cambrian was a different kind of process fromtoday” and expressed exasperation at gould’s repeated suggestions that “the cambrian was aperiod of evolutionary ‘experiment；’ evolutionary ‘trial and error；’ evolutionary ‘false starts。’ 。
。 。 it was the fertile time when all the great ‘fundamental body plans’ were invented。
nowadays； evolution just tinkers with old body plans。 back in the cambrian； new phyla andnew classes arose。 nowadays we only get new species！”
noting how often this idea—that there are no new body plans—is picked up； dawkins says：
“it is as though a gardener looked at an oak tree and remarked； wonderingly： ‘isn’t 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。’ ”
“it was a strange time；” fortey says now； “especially 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。”
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 “with contempt； evenloathing；” in fortey’s words。 “i have never encountered such spleen in a book by aprofessional；” fortey wrote later。 “the casual reader of the crucible of creation； unaware of the history； would never gather that the author’s views had once been close to （if not actuallyshared with） gould’s。”
when i asked fortey about it； he said： “well； it was very strange； quite shocking really；because gould’s 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 ‘oh fuck； another phylum’ and i expect he regretted being famous for that。”
what happened was that the early cambrian fossils began to undergo a period of criticalreappraisal。 fortey and derek briggs—one of the other principals in gould’s book—used 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’s 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’t as strange and various as they appeared at first sight。 “they were often nostranger than trilobites；” fortey says now。 “it is just that we have had a century or so to getused to trilobites。 familiarity； you know； breeds familiarity。”
this wasn’t； 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—just 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； “there are relatively few cambrian designs thatare wholly novel。 more often they turn out to be just interesting elaborations of well…established designs。” as he wrote in his book life： “none was as strange as a present daybarnacle； nor as grotesque as a queen termite。”
so the burgess shale specimens weren’t so spectacular after all。 this made them； as forteyhas written； “no less interesting； or odd； just more explicable。” their weird body plans werejust a kind of youthful exuberance—the 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—howthey 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—in 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—thatreally is a wonder—but 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—some grandfather species that started the line in amuch earlier past。
and the reason we haven’t found these earlier species； it is now thought；