In June of 1988 I attended the first Chapman Conference on the Gaia Hypothesis held in San Diego, CA. There I was introduced to James Lovelock and a host of other influential scientists studying Gaia, including Lynn Margulis, Stephen Schneider, Tyler Volk, and Lee Kump. This pivotal meeting set the stage for my career in exploring the science of Gaia.
In the 1990s I attended the three Gaia in Oxford meetings, which drew scientists like Stephan Harding, Andrew Watson, Susan Canney, and Tim Lenton, all of whom have made significant contributions to the science of Gaia.
In 1996, James Lovelock, Susan Canney and I co-founded the Geophysiological Society, later known as the Gaia Society, where I served as Vice-chair until the society was subsumed into the Geological Society of London in 2001.
Since then I have attended several meetings sponsored the Geological Society of London Gaia specialty group, including the Feedbacks in the Climate System meeting in 2004 and the Life and the Planet meetings in 2011 and 2014.
The 2014 meeting was officially titled Coevolution of Life and the Planet, and was well attended. Many of the attendees were younger scientists and graduate students from the UK. The keynote speakers included Lee Kump, Sir Crispin Tickell, and Tim Lenton, all of whom presented their latest thinking and results on Gaia theory. The remainder of the speakers were mainly younger scientists, or scientists relatively new to the subject of Gaia. The elders in the Gaia community, James Lovelock, Andrew Watson, Stephan Harding, and Euan Nisbet, were notable absent at this meeting.
I went into this meeting very hopeful of learning about the new directions in Gaian research, but near the end of the first day I was deeply disappointed. In the discussion period at the end of that day I made the general point that given the title of the meeting was about coevolution of life and the planet, why was there no mention in most of the talks about biological feedbacks on the environment.
By the end of the second day my disappointment turned to self-reflectance. Being a leader in the science of Gaia I have to take some responsibility for the direction, or lack thereof, in the discipline. I was most discouraged by the heavy reliance of the researchers on simple mathematical models of the earth. Most seem unaware of the severe limitations in the usefulness of such models when applied to a living planet.
The meeting in November has helped me see more clearly the directions that Gaian science has taken since I become involved in the late 1980s. I see four main paths that colleagues have taken in the field: theoretical Gaia, philosophical Gaia, empirical Gaia, and applied Gaia.
Theoretical Gaia is, nowadays, where all the action is. You can’t really be a part of this path unless you have a mathematical model of the system you are studying. Tim Lenton has championed the modeling approach to Gaia, and his fine skills as a scientist and communicator are a major reason why this area of Gaia has flourished in recent years.
In the late 1990s I dabbled a bit in using coupled non-linear models to shed light on Gaia, and was left feeling daunted at the task of understanding the earth through a math equation, no matter how sophisticated the formulation. All the physical and chemical models I have ever studied are nearly devoid of life. I despair if the future of Gaian science remains entrenched in the realm of modeling.
Philosophical Gaia is a path explored by thinkers such as Stephan Harding, David Abram, and Mary Midgley. Their writings on the philosophy and indigenous roots of Gaia have, in my view, been the most influential works on Gaia, aside from the writings of Lovelock and Margulis. Harding’s book Animate Earth and Midgley’s book Earthy Realism stand out as significant recent contributions in this area. Many non-scientists have been able to grasp the concept of Gaia through these insightful writings, a concept that inanimate models cannot convey to the masses.
Empirical Gaia is the basis of Gaian science. It was not a model that first inspired James Lovelock to conceptualize Gaia. It was the empirical observations of the atmosphere of the earth that first got him wondering. The scientific foundations of Gaia are grounded in empirical studies of biogenic gases and sulfur particles in the atmosphere. My own contributions to Gaia have focused on empirical studies of forests and peatlands and their role in carbon cycling and temperature regulation.
Most scientists studying Gaia have made empirical observations a part of their work, although these observations are usually made for the purpose of inclusion into models. While any and all observations related to Gaia are useful, there is a glaring lack of empirical studies that carefully examine any of the proposed biological feedbacks involved in Gaian regulation. In other words, there has never been a true test of Gaia, where all the elements of a proposed regulatory system have been simultaneously examined in situ.
The reason for this is that such an experiment would require a large interdisciplinary field campaign involving dozens of scientists with a broad range of expertise, and significant resources for supporting observational platforms. Unfortunately, Gaia is not the focus of most earth system scientists, and building a coalition of quality researchers to test Gaia theory is an endeavor that is not likely to happen in the current scientific climate.
Still, it is my opinion that any major advancement in our understanding of Gaia can only come from empirical studies. One day I envision a grand experiment, where scientists on ships, planes, and space stations, and in major ecosystems on all continents, join in the first real-time study of, say, the earth’s circulatory system, or respiratory system, or both. I do believe that day will happen, but probably not in my lifetime.
Applied Gaia is the use of Gaian principles to help solve real world problems. This is a path followed by scientists such as Susan Canney and myself. Canney has applied Gaian principles involving feedbacks of vegetation and wildlife to elephant conservation in Africa, and the success of her work highlights the worthiness of this approach. For my part, I have endeavored to apply Gaian principles involving forest succession to help restore oak forests in California. The positive results I have gotten, in turn, reinforce the validity of key assumptions on the role of forest succession in climate regulation of Gaia.
One of the findings Canney’s and my works have in common is the recognition that the past indigenous practices have played a major role in shaping the ecology in these systems.
In lieu of a major effort to test Gaia theory, I believe that applied Gaia is the next best way to investigate the living earth. If Gaian thinking leads to the solution of real world problems, then real progress is made in bringing Gaia to light.
I suppose it was inevitable that in the decades since its inception the science of Gaia would diversify into these and other branches of inquiry. A visionary future for a more fertile inquiry into Gaia should include a means by which these branches stay connected, a trunk that is more than an occasional meeting of the minds in London. Perhaps Gaia needs a real home, one that is open to any thinker and scientist who believes Gaia is an idea whose time has come.