A short history of nearly everything - Bill Bryson [165]
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 strange that no major new boughs have appeared on this tree for many years? These days, all the new growth appears to be at the twig level.' ”
“It was a strange time,” Fortey says now, “especially when you reflected that this was all about something that happened five hundred million years ago, but feelings really did run quite high. I joked in one of my books that I felt as if I ought to put a safety helmet on before writing 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 Conway Morris, who startled many in the paleontological community by rounding abruptly on Gould in a book of his own, The Crucible of Creation. The book treated Gould “with contempt, even loathing,” in Fortey's words. “I have never encountered such spleen in a book by a professional,” 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 actually shared 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 was embarrassed. You know, science changes but books are permanent, and I suppose he regretted being so irremediably associated with views that he no longer altogether held. There was all that 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 critical reappraisal. Fortey and Derek Briggs—one of the other principals in Gould's book—used a method known as cladistics to compare the various Burgess fossils. In simple terms, cladistics consists of organizing organisms on the basis of shared features. Fortey gives as an example the idea of comparing a shrew and an elephant. If you considered the elephant's large size and striking trunk you might conclude that it could have little in common with a tiny, sniffing shrew. But if you compared both of them with a lizard, you would see that the elephant and shrew were in fact built to much the same plan. In essence, what Fortey is saying is that Gould saw elephants and shrews where they saw mammals. The Burgess creatures, they believed, weren't as strange and various as they appeared at first sight. “They were often no stranger than trilobites,” Fortey says now. “It is just that we have had a century or so to get used to trilobites. Familiarity, you know, breeds familiarity.”
This wasn't, I should note, because of sloppiness or inattention. Interpreting the forms and relationships of ancient animals on the basis of often distorted and fragmentary evidence is clearly a tricky business. Edward O. Wilson has noted that if you took selected species of modern insects and presented them as Burgess-style fossils nobody would ever guess that they were all from the same phylum, so different are their body plans. Also instrumental in helping revisions were the discoveries of two further early Cambrian sites, one in Greenland and one in China, plus more scattered finds, which between them yielded many additional and often better specimens.
The upshot is that the Burgess