In using a dialectical approach to scientific problems, Gould restores a sense of history to natural history, reflecting a movement from subjective to objective that parallels change in human social history.
Richard York and Brett Clark, The Science and Humanism of Stephen Jay Gould (Monthly Review Press 2011), 223pp.
Darwin concluded his Origin of Species robustly claiming that ‘there is a grandeur about this view of life’, defending his theory against the inevitable objection that life is somehow devalued if it evolved rather than having being created. The scientist and writer Stephen Jay Gould borrowed the phrase for his monthly essays on ‘This View of Life’, through which he became known to a wide public, not least indeed for the sense of wonder and grandeur in the many peculiarities and byways of natural history. Yet exactly what the Darwinian view of life entails has been precisely at issue in controversies between Gould (and others sharing broadly similar perspectives such as Richard Lewontin or Stephen Rose), and other more mainstream figures, such as Richard Dawkins, or Daniel Dennett.
The facts of the evolution of life on earth have not been contested in reasonable circles for a very long time, but the mechanisms of evolution remained at issue for much longer. Darwinian explanations triumphed in the course of the first half of the twentieth century, but disagreements within ‘Darwinian’ theory remain important. Despite the standard notion that science is objective and non-political, the highly social-political ramifications of such notions as the ‘selfish gene’ are obvious. York and Clark, the authors of this book, highlight the rather more congenial implications of Gould’s thinking on natural history in the title itself: science and humanism. Rather than a limited and reductive field of reference, Gould’s learning was broad and his understanding of natural history, science and society was full and complex.
Gould’s opponents’ view of biology and natural history is reductive and atomising. This is the case whether in the guise of a ‘selfish gene’ theory (Dawkins’ notion that individual genes drive evolution and effectively reproduce the organism for the sake of their own survival) or Daniel Dennett’s argument that Darwinism is a ‘universal acid’ eating through the complexities of other fields of knowledge to reveal a simple truth behind them all. Gould’s view of life was not, like these examples, in tune with the neo-liberal triumphalism of the last thirty years. In contrast, Gould captured the multi-layered and multi-faceted sides of life on earth, seeing evolution in terms of dynamic tensions between, for example, developmental structures and natural selection. Gould criticised what is called the ‘neo-Darwinian’ consensus, or rather the ‘ultra-Darwinian’ interpretation of it, that leads to the faulty metaphor of the ‘selfish gene’, and to the various reactionary permutations of socio-biology and evolutionary psychology.
The resonance of the phrase, this view of life, appeared often in Gould’s writing, with a whole book, or at least the edition published in Britain, named after it, Life’s Grandeur (published as Full House in the US, 1996). Here a central recurring idea of Gould’s thinking appeared in full length: that evolution has no inherent drive towards complexity or any other substitute for the old notion of ‘progress’. There is no such thing as higher or lower animals, and human intelligence is not in any way a likely outcome of evolutionary processes. As Gould wrote, if you repeatedly re-ran the ‘tape’ of evolution from the beginning, it is highly unlikely that life on earth would on any occasion look remotely similar to the present configuration.
One would think this would be one of the less controversial of Gould’s ideas among materialist-minded scientists, but it seems not. The public dispute between Gould and Richard Dawkins over interpretations of evolutionary theory is well known. It is nonetheless a surprise to discover that Dawkins effectively allied himself with the somewhat theistic position of the palaeontologist Simon Conway Morris in the defence of a notion of ‘progress’ in evolution (pp.84-90). The dogmatic atheist Dawkins and the theistic Conway Morris both wish to see a deterministic trajectory to evolutionary history.
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| The Burgess Shale is probably the World’s most famous assemblage of fossils, made famous in particular by Stephen Jay Gould’s book Wonderful Life. |
Gould argued in contrast that evolution is contingent, dependent upon the interrelation of various factors, not the single ‘universal acid’ of adaptive selection; lacking any progressive drive; and subject to catastrophic disruptions. His hypothesis of ‘punctuated equilibrium’ posited that ecosystems normally remained very stable with little evolutionary change occurring over long periods, but that suddenly systems could break down in a wave of extinctions that also led to rapid evolutionary change (‘rapid’ in geological terms) and the emergence of a new equilibrium (pp.40-2). In this scenario, the ‘best adapted’ creatures do not necessarily survive the crisis; evolutionary survival cannot be mapped onto virtue, as some writers are wont to imply. Moreover the whole traditional notion of gradual, rational evolutionary development goes out the window. That the ultra-Darwinians reject this interpretation of evolutionary history so vehemently says more about their own ideological baggage than it does about the viability of the hypothesis.
It is in the plurality of forces acting on evolution in which the contrast between Gould’s sense of a dialectical totality and the reductionism of the ultra-Darwinians is made most clear, and is very well outlined in this book. Natural selection is a powerful, but not all-powerful force in evolution, and one of the major constraints upon it is the developmental structures of organisms. Once the basic ‘body plan’ of a type of organism has been decided, this limits the possibilities for all the later pressures of natural selection. That is to say, once the phylum of arthropods (insects, spiders, crustaceans and others) evolved, and sub-divided into its six and eight-legged varieties and so forth, then these creatures could not, even in the course of tens of millions of years, evolve an internal skeleton and vertebra instead of the arthropod body plan. More widely, there are all sorts of consequences for the lines of development that an organism can and cannot take as a result of its basic structure:
‘Hence the evolutionary process is a dialectical interaction between the internal (inherited structural constraints) and the external (environmental selection pressure, just as the ontogeny (development over the life course) of individual organisms is a dialectical interaction between their genes and the environment’ (pp.79-80).
Gould thus replaced the organism itself, rather than some collection of ‘selfish genes’ within it, at the centre of the evolutionary process; the whole creature being both the agent of natural-historical change as well as the object of natural pressures.
Gould restored a sense of history to natural history. He was certain that developmental structural constraints were themselves the result of essentially contingent events deep in the history of life. Yet once these structures came into being they became determinant of the directions in which life could develop. There is a movement from the subjective to the objective here that parallels change in human social history. The crucial difference between the two realms of history is the role of consciousness in human history, which alters the nature of this historical dialectic quite profoundly. Gould, while not an avowed Marxist, was clearly influenced by other dialectical approaches to scientific problems, and used the insights of this tradition to great effect.
All these issues, and many more, were explored in Gould’s brilliant monthly essays written between 1974 and 2001 for Natural History, and collected in book form for an ever wider international public across the years. However, it is another book, again for a popular audience, Wonderful Life (1989), which perhaps best concentrates the nature of the controversy over Gould’s view of evolution. This book covered the earliest period of multi-cellular animal life on earth, the period of the ‘Cambrian explosion’ some 500 million years ago. Here Gould’s infectious enthusiasm for his chosen subjects comes to the fore as brilliantly as anywhere else in his writing. You might not think you would be interested in tiny creatures living in muddy, shallow waters over half a billion years ago, but after reading this book, long extinct beasties such as Wiwaxia, Opabinia, or the aptly named Halucingenia will seem as important and as fascinating as any human ancestor. Gould’s conclusions regarding the meaning of these creatures and the Cambrian period have been sharply attacked since, but are still of great value.
One of the scientists most involved in the examination of the Burgess Shale fauna was Simon Conway Morris. Originally it was Conway Morris himself who described many of the Burgess Shale creatures as having body-plans that belonged in no known phylum. However he subsequently attacked Wonderful Life, arguing that in fact many of the Burgess Shale anomalies could be ‘explained’ by evolutionary relationships with the ancestors of other surviving phyla.
While the detail of this debate is quite technical and only open to specialists, as in to what existing phylum little Wiwaxia is most likely to be related, the larger nature of the argument is not complicated. If Conway Morris is correct about the evolutionary relationships of some of these marvellously weird creatures of the early Cambrian, he still seems to miss the main point of Gould’s argument. While many of the anomalous creatures have been ‘explained’ as belonging to stem groups in the evolutionary development of modern phyla, that does not negate Gould’s key argument concerning the once much greater diversity of body plans and the randomness of evolution. It may be that Opabinia can be shown to belong in a group which is cousin to the arthropods, but that does not make it actually just an early arthropod, or mean that Cambrian life was not much more greatly diverse in body-plan than subsequent fauna on earth. Moreover, if Opabinia’s body plan had triumphed, rather than that of the insect, life on earth today would look, and probably behave, very greatly differently.
There appears, to this observer at least, to be an element of the tendentious in the attacks on Gould’s general argument in Wonderful Life. The reaction, at least in part, reveals a powerful inclination towards finding the history of life to be an ordered affair that leads neatly to our present selves. Gould’s challenge to this tendency to biological teleology seems to have prompted attempts to caricature the argument the better to dismiss it (one of Gould’s own responses can be found here: http://www.stephenjaygould.org/library/gould_reversal-hallucigenia.html).
There is much more to Gould’s contribution to evolutionary science and our understanding of it than can be discussed here, not least his classic demolition of IQ theory in The Mismeasure of Man (1983 and 1996). Gould had a vast range, and took a lead in debates of crucial social importance, battling the racist and sexist implications of wave after wave of sociobiology and its successor, evolutionary psychology. It is a tribute to York and Clark that they are able to cover all the aspects of Gould’s work with clarity and satisfying scope in a fairly short book. It is to be hoped that this will help introduce more readers to the work of Stephen Jay Gould. Gould’s writing deserves a major place within a broad intellectual canon, not just for his arguments, but for the delight and wonder in nature and science itself that he was so adept at communicating.
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