The Burgess Shale is a collection of fossils of soft-bodied invertebrates that was formed soon after the Cambrian Explosion, an apparently rapid appearance of a many groups of complex animals. Initially discovered in 1909 by Charles Walcott, the fossils were later examined by three researchers in Cambridge; Charles Whittington and two graduate students, Derek Briggs and Simon Conway Morris. What began as an exercise to catalogue a group of ancient arthropods turned into the discovery of several new phyla of organisms, and ultimately changed the way evolution and selection were viewed. “Wonderful Life” by Stephen Jay Gould is a documentation of this process, exploring and explaining this new view of evolutionary change through Deep Time.
Although Gould was not personally involved in the cataloguing of the Burgess Shale organisms, he was in close communication with the people who were and his clear enthusiasm for the subject shows through. In the preface Gould sets out three main aims; to chronicle the intellectual drama that *was* the Burgess Shale examination, to explore the implications that this change in the perceived workings of evolution brought about, and finally to briefly look at *why* the discovery of the Burgess Shale seems to have passed so unnoticed by the general public, and even non-paleontological scientists.
The book is divided into five sections. The first sets up the central theme that the book is out to destroy; the iconographic idea of the March of Progress, that evolution is a kind of ‘onwards and upwards’ affair, with each generation leading to greater complexity. This was the idea that the discovery of new creatures in the Burgess Shale, creatures that belonged to no known phylum (and could therefore not be simpler and less developed forms of current animals) began to destroy. The second section covers background information considered necessary for an understanding of the Burgess Shale, a quick course on the Paleontological timeline and arthropod anatomy. Being the rather badly specialized microbiologist that I am, I read through these dutifully and promptly forgot them, so can safely say that it’s perfectly possible to enjoy the book without a great depth of scientific understanding.
The third section was for me the most exciting, as it was the actual description of the Burgess Shale creatures, written in order of their discovery (by Wittington, Briggs and Conway Morris). As they slowly discovered more new creatures, they began to realize that these were animals that had never been seen before, that had been wiped out by some extinction event. Furthermore, there was no particular evolutionary *reason* for certain animals to have been saved, the ‘March of Progress’ was beginning to look more like a lottery of chance. The last part of this section discusses the implications of this point of view, that humanity is not a strived-for evolutionary point of perfection, but simply a small twig on a tree of life which has had several branches snapped off altogether at different points in time.
The fourth section leaves the Burgess Shale (in a rather anticlimactic and in my opinion a slightly disappointing shift) to discuss Walcott, the man who found the fossils in the first place. Being a busy man, who in later life was caught up with various family tragedies, Walcott never properly had time to examine his fossils, and in the few papers he did write about them, he ‘shoehorned’ every fossil into modern phyla. Although I couldn't find the discussion of the life of an Edwardian scientist anywhere near as exciting as the beautiful fossil-creatures of the Shale, this section allowed a detailed examination of the shift in the way evolution was viewed as a theory, and why the original iconography of the March of Progress was so seductive and successful. In the fifth section Gould takes a brief but fascinating look at how things might have changed had life had a chance to play out a second time, if different branches of the tree of life had been cut off at different stages in history.
Overall I really enjoyed the book; I was especially pleased as this is (embarrassingly) the first book by Stephen Jay Gould I’ve ever read. The writing style is easily accessible, even to people with a very sketchy view of Deep History and the importance of arthropods, and is, a little surprisingly, highly immersive. The creatures of the Burgess Shale are so beautiful and wonderful that they stand up perfectly well on their own, and Gould lets them do so, his writing concentrating on exploring the philosophies surrounding their discovery rather than over-elaborate descriptions. The many accompanying pictures, most of which are the original drawings made by Wittington taken straight from the fossil samples, help to provide a wonderful visual image of the amazing and sometimes quite frankly weird creatures that populated the Burgess Shale.
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For those interested in such things, I now have a twitter. Like the blog, it will be strictly sciency, rather than personal and will be updated far more often.
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