Given his intention in Wonderful Life to explain “the nature of history itself,” we might expect Stephen Jay Gould to describe the rise and fall of nations and states, the triumphs and tragedies of great leaders, or even the daily comings and goings of ordinary people in ordinary circumstances, especially since he pays homage to Frank Capra's 1946 film It's a Wonderful Life. But the book's subtitle, The Burgess Shale and the Nature of History, tells us that Gould's interest is something else: the nature of history revealed in the Burgess Shale of British Columbia, the most significant of early Cambrian fossil deposits. Discovered in 1909 by Charles Doolittle Walcott of the Smithsonian Institution, the Burgess Shale records an astounding proliferation of marine life forms which occurred about 530 million years ago, during a moment in geologic time virtually simultaneous with the so-called “Cambrian explosion” of some 570 million years past, when multicellular organisms with soft body parts first appeared in the earth's prehistoric seas.
Committed to Darwin's nineteenth-century evolutionary gradualism, the belief that history tells the story of progress and predictability, Walcott viewed the Burgess organisms as primitive ancestors of more complex modern forms of life. To Gould's Kuhnian ways of thinking, however, the Burgess Shale tells the story of contingency—of how unpredictable antecedent events unleash an irreplicable cascade of historical consequences, which do not in and of themselves denote progress. In the case of the Burgess fauna, evolutionary contingency involved the wholesale decimation of no less than seven complete phyla and the disappearance of at least thirteen unique arthropod anatomies. Although the Burgess decimation does not match the extent of the late Permian event of about 225 million years ago which saw the extirpation of perhaps 96 percent of all marine life forms, it nonetheless calls into question Walcott's views that progress, predictability, and gradual diversification describe the correct underlying pattern for any evolutionary taxonomy which traces multiple branches to a common trunk.
To reject Walcott's views is no easy task, Gould recognizes, for there are enormous stakes involved when attempting to displace the ideas of progress and predictability with the notion of contingency. With its implications of the unpredictable and chancy, contingency simply does not satisfy one of our culture's deepest hopes: that life has evolved, history has developed, in some meaningful way. Gould also understands that when yesterday's scientific heroes—men such as Walcott, “one of the most extraordinary and powerful scientists that America has ever produced” (240)—come to be judged as hidebound ideologues by today's standards, then scientific change exacts an enormous price, the virtual eradication of a researcher's accomplishments from historical memory.
In fact, Gould's reluctance to pay that price explains how he structures the lengthiest section of his book, “The Burgess Drama,” a Kuhnian narrative told in the form of a five-act classical play, of how Cambridge paleontologist Harry Whittington and his graduate students Derek Briggs and Simon Conway Morris came to question the work Walcott published in the first decades of this century....