Bruce Clarke (ed.), Earth, Life, and System: Evolution and Ecology on a Gaian Planet (New York: Fordham University Press 2015), xiii+347 pp. Pb $35, $95 Hb. ISBN: 9780823265244
Lynn Margulis (1938-2011) was one of the boldest and most imaginative evolutionary and ecological theorists of the late twentieth century. Although her name does not appear on the title page of Bruce Clarke’s recent collection of essays, the words ‘system’ and ‘Gaian’ in the title give the clues that the book is going to take her science and her values as its starting point. Margulis was the founder of Serial Endosymbiosis Theory (SET) and James Lovelock’s principal collaborator in developing Gaia Theory or Earth system science. In SET, she postulated that chloroplasts, mitochondria and other components of eukaryotic cells originated as independent micro-organisms, and that the moments of symbiosis which saw their incorporation into other cells as living systems were crucial saltations within evolutionary history. Where SET has been widely accepted within science, Gaia remains contentious, in part because of the personification implied by the name itself. Margulis did not set out to court controversy, but nor was she shy of it, and rather than settle into participating in normal science she pursued her own independent research and fostered that of others with conviction. Clarke’s collection at once pays tribute to Margulis’s own work and presses on in the same spirit. As he explains in his introduction, these ten essays started life as papers for a symposium on Margulis’s research and the kinds of holistic, unconstrained science she worked to promote. Margulis herself was to have been the guest of honour, but she died as the preparations were under way. Clarke and his co-organisers went ahead with the symposium, now held in her memory and honour, and then gathered this collection together on that basis.
The breadth of Margulis’s thinking and its ramifications for our understanding of biology, ecology and our own place in the world are impressively demonstrated by the range of the essays in this collection. The book opens with a fluent and intimate defence of Margulis’s vision and scientific practice by Dorion Sagan, her son and longstanding literary collaborator. Sagan’s chapter prepares us well for the radical shifts of perspective entailed in following Margulis’s visions of nature, as individual living things become multiple complexes of symbionts while the Earth itself emerges as a single vast symbiotic organism. The nine chapters that follow can be categorised under different headings – scientific arguments, historical and cultural studies, political interventions – but the structure of the book refuses to assert such taxonomies and many of individual essays themselves resist them no less determinedly. Instead the book moves fluidly from one disciplinary focus to another and back, offering a holistic worldview grounded in science yet alert to its own history and acutely aware of its political contexts and implications. Within this worldview, different essays bear different relations to Margulis’s work, some examining it directly, others making more tangential connections or putting across theories that, while not directly linked to Margulis’s own work, are consistent with her findings or in sympathy with her approach. At the same time, the possibilities for debate and disagreement are never foreclosed, as at the core of Margulis’s project, sustained by Clarke and his collaborators, is the insistence that science, in order to accomplish its investigations, has to retain an imaginative freedom which, paradoxically, stops it from ever becoming ‘normal’ in the Kuhnian sense.
The most direct interventions in science in the collection come from Sankar Chatterjee, James Shapiro and Susan Oyama. Chatterjee mounts a plausible argument for the origin of life through a process analogous to Margulis’s serial endosymbiosis which he calls ‘serial endoprebiosis’ (69), charting the successive stages through which the component parts of living, replicating cells may have come together. Shapiro makes a compelling case that natural genetic engineering, by which cells are able to effect changes to their own genomes and incorporate DNA from other organisms and viruses within their immediate environment, has been a major driver of adaptive evolutionary change. Oyama’s explication of how developmental systems theory helps to account for – indeed, is a necessary tool for thinking about – evolutionary change and ecological relations is if anything still more convincing. What all three arguments share with one another, and with Margulis’s own research, is the recognition that, within a Darwinian world, all relations, internal and external, are necessarily ecological and interdependent. There are no essences, only organisms in perpetual flux existing through time and their relations to one another and their own composite, changing selves. As Sagan remarks in his essay, ‘Evolution is Heraclitean’ (30).
The chapters by James Strick, Jan Sapp and Susan Squier help to situate these interventions in relation to Margulis’s own science and that of her contemporaries, giving the collection its historical depth. Where Squier concentrates principally on the models of theoretical biology in play in C H Waddington’s thought and the interdisciplinary symposia he organised in the 1960s to try and develop a General Theoretical Biology, Strick and Sapp are more directly concerned with Margulis’s own research. Strick’s essay is an exemplary piece of narrative history of science, showing how both Gaia Theory and SET emerged from the specific research and funding context of the exobiology programme at NASA, again in the 1960s, and how this original context went on to shape their reception among the wider scientific community. Sapp’s comparably crisp and stimulating chapter places Margulis’s research on symbiosis as a major force in the emergence of complex organisms within a longer historical sweep, tracing the genesis of this idea back into the nineteenth century and considering how it played out in the competing versions of the tree of life devised by Margulis and Carl Woese at the end of the twentieth century. Sapp’s conclusion, that symbiosis ‘belies the classical concept of the organism comprised of cells whose cooperation results from a common genome’ (126), returns us from the history to the science itself, paving the way for Shapiro’s and Oyama’s articles later in the volume. Strick’s essay similarly sets the stage for Clarke’s, which is the only essay in the collection on fiction. Clarke examines the resonances with and refractions of Gaia theory in what he calls the ‘planetary imaginary’ of Frank Herbert’s Dune and William Gibson’s Neuromancer. Clarke’s reading of the space colonies in Gibson’s novel alongside the depictions of similar colonies imagined by artists working for NASA on self-sustaining Gaian principles deftly teases out the novel’s critique of the possibility of a sustainable technological fix to our ecological and ethical disasters.
The political implications of Margulis’s worldview are implicit in Sagan’s and Clarke’s essays and are spelled out by Oyama in the conclusion to her chapter, where she reads Ursula Le Guin’s story ‘The Ones Who Walk Away from Omelas’ as an allegory for our own predicament, mired in ecological exploitations which leave ‘no clean hands’ (224). The last two essays in the collection intensify this political focus. Christopher Witmore appals us into ethical revulsion with the steady accumulation of grotesque details of intensive beef farming in his account of Cattle City in Texas. His characterisation of the animals’ existence as ‘being-toward-slaughter’ is a ghastly but all too literal re-working of Heidegger’s ‘being-toward-death’ (236). The final essay of the collection, by Peter Westbroek, offers a glimmer of hope in a narrative that proposes the emergence of Earth system science as heralding a new stage in human history, ‘a civilization observing symbiotism’ (267). One test case, Westbroek proposes, will be whether or not humanity opts to pursue fracking for shale gas, causing ‘serious lesions in the memory of the Earth’, or whether the ‘awakening of a planetary consciousness through science’ can arrest this act of ‘vandalism at a scale never paralleled in history’ (266). On these terms, the hope may be slim but is no less vital for that.
Altogether, Earth, Life, and System offers a series of often fascinating, always stimulating, at times hyperbolic, at times tenuous, but invariably enriching essays in an incisive and unruly science and its existential repercussions. It is a fitting tribute to one of modern science’s most generative and productive independent spirits, a gadfly like Socrates whose ultimate concern was to ensure that enquiry and debate were never stifled by received opinion and ‘normal’ expectations.
John Holmes, University of Birmingham