Homage to Gaia (43 page)

Lynn and I were strange opposites to be so closely connected by Gaia. Lynn was at her best in the centre of a group of good students, giving and taking. I was at my best alone and thinking. Together, we explored endlessly the possible systems involving the biota that could serve as Gaian regulators of climate and chemistry. Lynn opened for me the world of natural micro-organisms. I knew one end of a bacterium from the other, having spent my time doing clinical bacteriology, and I knew a little about the multitude of natural airborne organisms that have nothing to do with clinical bacteriology. I knew this from my days sampling the air of London, but I knew almost nothing of the great world of micro-organisms that has existed from 3.5 to 4 billion years ago until now. Through Lynn and through her scientist friends, like the micropaleontologist ES Barghoorn at Harvard, I learnt how important these are and have been since life began 3.7 billion years ago. Big things like trees, elephants, and whales, lesser ones like shrubs and humans, and tiny things like worms and insects, all are recent. During the period that we worked together, other scientists were glad to hear us tell our tale, but rarely ever would they take it seriously. It remained an entertainment, a flight of fancy.

In the early days, we were somewhat outrageous in our statements. We had to be. We were in a way like a neglected child who behaves badly if this is the only way for him to attract attention. I used the metaphor of a living Earth provocatively to make some humourless biologists think I really thought the Earth was alive and reproduces.
Of course, I did not. Our papers and my book allowed our critics to be more focused so that we could take them more seriously. For me, this led to model making, but Lynn, with that wonderful feeling for the organism that is the good heart of biology, had little time for abstract models and took a more direct approach.

An important step in the evolution of Gaia theory took place at a Gordon Conference on Atmospheric Chemistry in August 1971. These conferences are one of the best features of American science. During vacation time, the private boarding schools that spread across upper New England, mainly in New Hampshire, use their accommodation to host dozens of scientific conferences. The better ones are gatherings of actively working scientists who report their latest findings and ideas to an audience of their peers. There are rarely more than sixty present and their talks are not published, even as a conference report. Presentations take place in the mornings and evenings; the afternoons of the conferences from lunch until dinnertime are free for walks in the mountains or swimming in the lakes of that beautiful part of America or, of course, for quiet, intense debates, sitting on the terrace of the school.

As a frequent attender at Gordon Conferences I enjoyed the fringe benefits such as climbing one of the small granite mountains near New Hampton, the site of the 1971 conference. The guide who led us up Mount Cardigan was dubious about my capacity, at fifty-one years old, to keep up with younger men and women who had chosen to spend their afternoon this way. Having climbed Snowdon, a Welsh mountain of the same height, by the exciting Crib Goch the previous year, I told him that I thought I could manage. It was a glorious afternoon walk up a rocky pass, first through a pine forest and clear streams, and then up onto the smooth assembly of granite slabs, mostly bare, that led to the mountain top. As always, at the top there was a feeling of achievement and the reward of a grand view of the lakes and mountains of northern New England. I must admit to having misjudged the beauty of the New England countryside. New Hampshire, Vermont, and Maine were more attractive to me than the states further south.

The next afternoon I spent swimming in the lake and then walking along its beach with the German scientist Dieter Ehalt from NCAR. We talked about methane. Dieter was the acknowledged leader of research on the production and fate of this important atmospheric gas. I had long been interested in its significance as evidence for a
self-regulated atmosphere and one of the props of Gaia theory. As we passed a small, slow-moving stream that flowed into the lake, Dieter took a stick and stirred the black detritus at the bottom of the stream. A burst of bubbles came forth. ‘There’s the methane,’ he remarked. I had known that about 500,000,000 tons of the gas escaped from the ground into the air each year, but this simple demonstration fixed forever in my mind its reality. My long-time friend from Boulder, Jim Lodge, had organized this Gordon Conference on Atmospheric Chemistry and it was an outstanding success. The thirty years of important and exciting atmospheric science that followed owed their start to that meeting. We talked of future climates, the effect of greenhouse gases and the cooling by clouds and aerosols. We discussed at length the chemical cycles of the elements. Here, also, I presented my measurements of the atmospheric abundance of CFCs and DMS.

At this same meeting, Joe Prospero talked about atmospheric aerosols and the composition of dust collected at stations in Florida and even in Hawaii. I was amazed to hear that Sahara dust blew all the way across the Atlantic and even into the Pacific. We also argued over the super abundance of elements such as sulphur, selenium, iodine and zinc in the aerosol particles. I speculated that perhaps biological methylation rendered these elements volatile and carried an excess of them into the atmosphere. Here were the first steps towards the discovery years later with Bob Charlson, Andi Andreae, Steve Warren, and myself that clouds, dimethyl sulphide from algae living in the ocean, and climate, are all intimately linked in a great ocean atmospheric cycle. My report at this meeting on the prevalence of CFCs in the troposphere led Lester Machta later to alert Sherry Rowland to this source of chlorine in the atmosphere, and to the recognition that chlorine in the stratosphere might catalytically deplete the ozone there.

GD Robinson came to me one afternoon and said, ‘Could you give us a ten to fifteen-minute talk on Gaia after dinner tonight?’ He introduced me that evening as someone who would entertain them with a flight of fancy. It was my first talk on Gaia to an audience of atmospheric scientists and I published it in
Atmospheric
Environment
two years later with the title ‘Gaia as seen through the atmosphere’.

During the 1970s and until 1982, when I fell ill, Lynn Margulis and I spent as much of our time developing Gaia as we could. Neither of us received support for our work, and both of us were busy with
other work. Lynn had her teaching and other duties at Boston University, and I had my customers, as well as the burgeoning ozone depletion research. We published two important joint papers. I wrote the first, ‘Atmospheric homeostasis by and for the biosphere: the Gaia hypothesis’, and it expresses Gaia as I then saw it. The second, ‘Biological modulation of the Earth’s atmosphere’, Lynn wrote, and it expresses her view of Gaia. These titles reveal our ignorance then of the fact that regulation is a property of the whole system of life and its environment, not just life itself. A high spot in this period was an expedition organized by Lynn, who gathered the funds to enable a party of scientists to visit Baja California and do research on the algal mats there. She took us from San Diego to Laguna Figueroa, a place about 200 miles down the Baja California peninsula. Algal mats are the communities of micro-organisms whose ancestry dates back to the Earth’s earliest history and may have played a huge part in regulating the Earth system over the whole of that time.

We met in a small hotel near the Scripps Institute at La Jolla, a cosy, wealthy institute, and so well sited on the shore of the Pacific. Almost as comfortable, I thought, as Coombe Mill. We travelled south in two people-carriers and passed across the border and through the dismal town of Tijuana, and then down the Baja peninsula itself. The real Mexico revealed itself as we travelled south. When we arrived at our destination, we found that we were booked into a small hotel. Having suffered from eating at American–Mexican restaurants, I rather dreaded a week of Mexican food. I could not have been more wrong. The food at our hotel was magnificent, and I found myself looking forward with anticipation to every meal. National cuisine gets a bad name from its restaurants in the capital cities of the western world.

Along the edges of the continents, earth movement and the drifting of sand and shingle forms lagoons that trap ocean water. In the warmer parts of the world, these lagoons lose more water by evaporation than they gain from rainfall or from sea water leaking in from the ocean. Consequently, the salt in the water concentrates until it crystallizes to form what the geologists call an evaporite deposit. This process has been going on since the beginning of time and we find evaporite beds buried under sediments all over the world. They form the huge salt deposits, like the one that runs across northern Europe a few hundred feet below the surface and is made notorious by the salt mines of Eastern Europe. The algal mats sit on top of these evaporite
beds. Lynn, her student, Greg Hinkel, and I speculated about the role of these mats in sustaining salt in the beds, and so keeping the ocean below the critical salt level of 0.8 molar. Above this salinity, organisms find it hard to survive. I watched as Lynn cut out with a small spade a cube of the mat four inches in size. We looked at its banded structure: each band was a different community of micro-organisms segregated according to the flow of nutrients and oxygen. Lynn showed how similar was this banded structure to that of the fossil mats over two billion years old. I was convinced by her lucid explanations that micro-organisms are the heart of Gaia and always have been.

On one occasion, I went with Lynn, her daughter, Jenny, and a French au pair girl, to another Gordon Conference in New Hampshire. We gave our Gaia talks and soon discovered that we were not there as serious scientists but more as entertainment. The serious business of the conference, we discovered, focused on arcane topics dear to the timber industry. This allowed us plenty of time to explore the New Hampshire Mountains. We had just climbed one peak and were making our way down over the granite boulders and small shrubs, talking passionately about a Gaian problem, when suddenly we found ourselves deep in the forest. We were lost. Lynn gave a cry: ‘There are thousands of miles of nothing between here and Canada and if we go the wrong way they will find our bodies in the spring.’ We tried to retrace our path, and with luck, came upon a logger’s trail, which we followed down to the road, but it was a scary moment. As time went by, Lynn and I saw less of each other, mainly because the forces of family life and work were dispersive not cohesive. It was the best of my lifetime collaborations and was a platonic relationship that kept in a lively steady state. The sad events in both our families conspired to separate us as active scientific colleagues in the 1980s but we both continued to develop Gaia in our own ways. My friendship with Lynn has grown with the years and it now includes my second wife Sandy, and embraces her own partner, the distinguished Catalan scientist, Ricardo Guerrero.

Well-disposed non-scientists seem to think that science is founded on impeccable measurements and based in certainty. Scientists sometimes act upon this myth and become as dogmatic as are the religious. Remember Einstein’s famous denigration of the quantum theory, in a personal letter to Max Born, which is often summarized as: God does not play dice with the Universe. The radical French philosopher, Michel Foucault, said, ‘The truth is not discovered: it is something
produced by the elite.’ He was talking of politics but his observation is true of science also. The truth at any time trickles down from the heights of the eminent. If senior biologists, respected by their peers, say life adapts to its environment, then this becomes the working dogma of biology. If senior geologists, similarly respected, say the presence of life is not needed to explain the evolution of the rocks, this also becomes a dogma. Together, these dogmatic beliefs become the conventional wisdom of science. It is in our nature to seek certainty. Because of their ‘faith’ in the conventional wisdom, most scientists rejected our life-detection experiments and Gaia theory when they were first proposed. They did so with that same certainty that the religious have when they reject the views of a rational atheist. They could not prove us wrong but they were sure in their hearts that we were. Lynn and I were astonished at what seemed to us a most unscientific attitude on the part of our peers, and by the scorn of their rejection. I was an innocent to expect Gaia’s acceptance, and truly foolish to imagine that such a radical theory could succeed in such an environment. It had as little chance of success as would a proponent of market capitalism have had in Lenin’s Russia.

The early 1970s were exciting yet frustrating. I read GE Hutchinson’s wonderful chapter called ‘The Biochemistry of the Earth’ in a book on the solar system and found that he came quite close to my own views about the Earth. He seemed to draw back from seeing it as self-regulating and went no further than to say it was an interesting chemical anomaly. Sometime during this period, I tried to have a talk with him during a brief visit to Yale University. There was also present at the meeting the geochemist, Jim Walker, who strongly, but in a friendly way, disagreed with my views, and did not hesitate to speak out against them. Both Hutchinson and I were somewhat quiet speakers and needed time to digest our exchanges. The threesome did not work and we achieved little. Sadly, I was never to have another opportunity of meeting Hutchinson before he died. I regret not reading Eugene Odum’s papers at this time for he alone understood that an ecosystem is a deterministic feedback system, which is how I saw Gaia: in many ways Gaia is the ecosystem of the Earth.

The first real stirrings of public interest in Gaia followed the publication of a paper written with my friend, Sidney Epton, of Shell. The title was ‘The quest for Gaia’ and it appeared in
New
Scientist
in 1975. This paper did attract attention from the media. I received twenty-one letters and telegrams from publishers inviting me to write a book on
Gaia. I chose Oxford University Press mainly because they sent a most personable representative, Peter Janson Smith, someone I liked and could easily work with. The book took four years to write and appeared in 1979. Its publication completely changed my life and the fall of mail through my letterbox increased from a gentle patter to a downpour, and has remained high ever since. To my astonishment, the main interest in Gaia came from the general public, from philosophers and from the religious. Only a third of the letters were from scientists. I never intended the book as a science text for specialists, but I did expect them to read it. I have always thought that science should be accessible to any intelligent person. Science affects our lives and that of the Earth so much that it would be monstrous for it to retreat to a world of jargon accessible only to the denizens of cosy ivory towers. I wrote the book as if it were a long letter about Gaia to a lively intelligent woman.