The Living Earth: The Gaia Hypothesis

One of the major ecological philosophies to have risen in modern times is the Gaia Hypothesis, whose main proponent is Dr. James Lovelock. This ecological concept argues that the entire world may be seen as a single living entity made up of complex elements and interdependencies.  The name Gaia was derived from the Greek goddess of earth, and she became the rallying symbol for environmentalists and ecologists who believe that our disregard for Mother Earth will be the ultimate cause of humanity’s downfall.

            The Gaia Hypothesis first rose to public consciousness in the 1960’s. At that time, Dr. James Lovelock was working on discovering life on Mars as per NASA’s request. As a means to determine if life existed on Mars, Lovelock employed a top-down view of the planet be employed. This top-down approach started with examining the atmosphere and proceeding downwards, into the smaller elements found in Mars. Lovelock theorized that if life existed on Mars, then its atmosphere would show signs of disequilibrium resulting from the metabolic activities of living organisms. (Lovelock, 2000, p. 35)

Tests show that Mars had an atmosphere that was very stable and constant, while the Earth had a highly dynamic atmosphere that changed every now and then. Based on these findings, Lovelock concluded that Mars held no life forms, which was confirmed upon Viking landings on Mars following Lovelock’s statements. The dynamic nature of Earth’s character became a springboard for the Gaia Hypothesis. Based on this, Lovelock had the idea that Earth’s atmosphere was constantly shifting because it was constantly righting itself, seeking homeostasis. The changes in the atmosphere are actually manifestations of a feedback system that allows for self-regulation. This self-regulating mechanism which lies at the heart of planet Earth is what he called Gaia.

Indeed, it is a bit paradoxical that Lovelock’s inspiration for a living world should come from an inert and lifeless planet. But as with most strokes of genius, inspiration often comes from the unlikeliest of places. By the late 1960’s Lovelock had a working theory. In the early 1970’s Lovelock pursued this theory and went on to publish his findings in scientific journals. By the end of the 1970’s Dr. Lovelock went on to write a book which he entitled: Gaia: A new look at life on Earth. His book created a buzz and his hypothesis captured the attention and imagination of scientists and environmentalists alike. Perhaps a big reason for the success of Dr. Lovelock’s idea is that he is able to come up with a great name. The name Gaia conjures images of a powerful being, but one who still needs to be protected. This stroke of genius was suggested by writer William Golding, who at that time was Lovelock’s neighbor. The use of a strong yet vulnerable goddess as an image for the Earth has been instrumental in the reaction that Lovelock’s hypothesis generated. The act of humanizing the Earth has really changed the way people look at the world, and things have never been the same since then.

Since the inception of the concept, The Gaia Hypothesis has been used to successfully predict natural events and phenomena and has been implicated in various researches and experiments. What is most interesting about the hypothesis, apart from the concept itself is that it has generated very strong emotions, either for or against the theory. The main support comes from environmentalist groups and climatologists, while most of the protest comes from traditional biologists. People who support or challenge the idea are very passionate about their beliefs and it is very difficult to find a person who does not hold a particular stand about it, whether the come from the world of science or not. While debate still rages as to the viability of the Gaia Hypothesis, one noted scientist, Dr. Lynn Margulis, become Lovelock’s staunchest supporter. Together, they collaborated on most of the Gaian concepts that buttress their model.

            How do we exactly define the Gaia Hypothesis? To quote Dr Lovelock on his first book, We have since defined Gaia as a complex entity involving the earth’s biosphere, atmosphere, oceans, and soil; the totality constituting a feedback or cybernetic system which seeks an optimal and physical and chemical environment for life on this planet. (1971, p. 10)

            The main concept of the Gaia Hypothesis is the interdependence of systems and elements found therein. The Gaia Hypothesis makes an analogy that compares the Earth to a living, breathing organism whose body is a complex system of parts that all work together and interact to create an internal balance. This idea revolves around the concept of self-regulation or feedback, where the organism is able to monitor itself and act accordingly to upright itself in case there is an imbalance or shift in conditions. In animals, this optimal state where the organism can function without any problems is called homeostasis, and is a term that Lovelock used for Gaia as well. Gaia always seeks for balance and acts towards homeostasis to protect itself and all the elements that depend on her.

This holistic view of our planet earth has some important implications on us human beings. Man, being the most dominant and most influential organism on Earth, ultimately has the power to determine the course of the earth and Gaia’s destiny. Advances in modern technology are creating a shift in the balance of power between Mother Earth and mankind. (Lovelock 2000, p. 11) But regardless of this, both Earth and Man exists on an implicit system of interdependence. Man depends on Gaia as Gaia depends on the Earth. The Gaia hypothesis translates to a warning that mankind should mend their ways lest they set on a course that would irrevocably damage the Earth to the point that it is beyond repair and healing.

The core of Lovelock’s hypothesis is that the Earth is a responsive organism capable of making regulatory decision, and that all life and natural life forms acted according to this regulatory or control mechanism. As such, every entity on this planet is not an isolated, independent unit, who acted based on individual interests alone. In effect, the Gaia Hypothesis believes that everything on Earth acts in cooperation with one another, seeking to self-regulate and achieve homeostasis. There is an internal control mechanism, like a huge thermostat, which measures conditions and acts accordingly to adapt and repair. To prove his hypothesis, Lovelock pointed to the salinity of the ocean and the global temperature as indicators. He argues that these elements have kept themselves within consistent levels in spite of the many changes going on around them. If earth were inert, then it would not have been able to constantly control these variables and keep them within “normal” limits. Dr. Lovelock then goes on to give more proof to support his Gaia Hypothesis. Dr. Lovelock argues that Gaia keeps the oxygen content in the atmosphere within levels that are supportive of life. Gaia constantly monitors these oxygen levels and makes adaptive changes in case these levels exceed to fall below tolerable limits. All actions of Gaia are done to protect life and keep physical conditions conducive to living.

Therefore, Lovelock proposes that living organisms do not inhabit an inert Earth, where they have to constantly accustom themselves to. Rather, the Earth and living creatures constantly interact with each other to reshape the environment in ways that promote and support life. (Margulis & Sagan, 1986). Prior to the inception of the Gaia Hypothesis, much of our views about life, evolution and the environment are dominated by traditional and conservative scientists who believe that the Earth is inert and passive, and that evolution is a wonderful accident. Evolution was about survival of the fittest, where organisms mutated and changed for their own selfish interests. The Gaia Hypothesis flies in the face of all of that. In the world of Gaia, organisms evolve because of a collective desire to make the world a better place. The Gaia thesis maintains that the Earth acts more like a biological organism and where some systems are more vital than others. (Joseph 1990). Among these crucial systems are rain forests and oceans, as well as the polar ice caps and atmosphere. While Gaia might be able to repair itself during minor injuries, it can only sustain so much damage to its vital “organs” before it collapses and dies.

The Gaia Hypothesis is actually a two-fold model: the environmental aspect and the biological aspect. The biological facet is handled by Dr. Margulis, a renowned microbiologist who has accomplished much in the field independent of Lovelock’s own. Margulis argues that evolution is not a product of random mutation, where organisms adapt to their environment on a trial and error basis.  Margulis contends that organisms are not hit-or-miss, they are sentient organisms capable of making intelligent decision. When these organisms change or mutate, they do so with deliberate intention, in response to what is going on in their environment. Organisms are constantly interacting with their environment and this constant interaction creates a change in the individual over time. Margulis frames her theory upon the belief that all life has a common chemical origin (Margulis and Matthews, 2000, p. 47) and thus, acts more or less in the same way.

Lynn Margulis and Lovelock have been collaborating for more than a quarter of a century. Around the same time as Lovelock was forwarding his Gaia Hypothesis, Dr. Margulis was also releasing her theory of endosymbiosis. Endosymbiosis argues that organelles or intra-cellular structures evolved from independent microorganisms living inside another organism, acting like a parasite or a predator cell. (Margulis and Fester, 1991, p. 100) Soon, both these organisms realized that they have better chances at survival if they enter into a symbiosis. This symbiosis further evolved and refined, until over time the separate organisms fused into a single entity or creature. In the cellular level, this translates to organelles evolving from microorganisms and becoming specialized, with specific functions within the cell. Margulis’ endosymbiosis is central to the Gaia Hypothesis because the concept of organisms acting in the mutual interest of one another is a microscopic metaphor for Lovelock’s Daisyworld. The Gaia Hypothesis envisions a world where all organisms contribute and interact to retain the Earth’s balance and make it conducive to living. The symbiosis not just occurs among microorganisms but extends to the totality of life on Earth. This symbiosis is a manifestation that living creatures can directly manipulate the environment and itself for its own purposes. In the words of Samson and Pitt, “Life optimizes its environment to suit itself.”  (1999, p. 123)

Both the Gaia Hypothesis and endosymbiosis were groundbreaking notions which shook the science world to its very foundations. These new theories challenged age-old ideas and forced people to think out of the box. As such, both Margulis and Lovelock were misunderstood and were even mocked by some quarters. Both scientists found that each of their individual theories propped up or supported the other. Thus, they came together and have been collaborating since then, with each handling different facets of the Gaian concept.

Other supporters came to the fore and championed the cause of Gaia. Some scientists saw in the Gaia Hypothesis the validation of their own studies. In support of the Gaia Hypothesis, a theory was forwarded about the emergence of complex organisms. The lowering of atmospheric carbon dioxide was the impetus for the evolution of more complex organisms, and this lowering is secondary to the weathering action of simple life forms on minerals. (Schwartzman, 1999) In a sense Schwartzman makes the argument that the Earth and earthly life forms act within a deliberate and purposive framework, and not because of some random or accidental physical occurrence. Stephen Harding, a Gaian ecologist who has worked with Lovelock on computer models and simulations, purports that the main enemy of the Gaia Hypothesis is orthodoxy or the stubborn clinging to old ways and beliefs. Harding is one of the proponents of the Deep Ecology movement, which advocates oneness with nature. Andrew Watson, Lovelock’s partner in the creation of Daisyworld, defends the Gaia Hypothesis by saying that the complexities of life make us near-complete ignorants about the mysteries of life. At best, our theories are best guesses and conjunctures. He then supports the Gaian theory by stating that the Gaian biosphere started with the emergence of photosynthesis. (

The main criticism of Lovelock and Margulis’ theory is their concept of ‘Gaia’ as actual living and breathing organism. (Kellert and Wilson, 1993, p. 354) Indeed while Lovelock and Margulis’ ideas are very compelling and convincing, it is difficult to accept that our planet is actually alive, as per our definitions of life and living. The enormity of the concept is also difficult to grasp given the vastness of our planet. Moreover, the hypothesis is hard to accept because the Earth as an organism is something that we cannot observe outside ourselves. (Russel, 2000) As inhabitants of the Earth, we cannot move away from it and study it in isolation of ourselves and see it in a bigger perspective. Russel in his book, The Global Brain Awakens, suggests that to see the Earth as an organism requires us to see things in a greater, grander scale. As per his own words, To better understand the planet as a living system, we need to go beyond the time scales of human life to the planet’s own time scale, vastly greater than our own… we would see the atmosphere and ocean currents swirling round the planet, circulating nutrients and carrying away waste products, much as the blood circulates nutrients and carries away waste in our own bodies. (2000)

Russel then goes on to argue that similarities between living systems and the Earth’s mechanisms are apparent, but what really matters is whether mankind will be able to accept and regard our planet as a living, breathing organism, in which we are but a small part, albeit a powerful component? (Russel, 2000)

It might be said that the criticism to the Gaia hypothesis is due to the strong statements of Lovelock in his first book about the living nature of our planet, which was generally theoretical and philosophical in approach. Indeed, while much has protest has been thrown against the Gaia Hypothesis, they are fairly limited to the seemingly unacceptable notion of an actual living Earth. Some scientists insulted the name but gave very little refutation to the hypothesis. Ford Doolittle challenged the Gaia Hypothesis in 1981. In a published article, Doolittle countered that organisms do not have the feedback mechanism that Lovelock and Margulis were talking about. (1981) He goes on to say that nature cannot act with deliberation and foresight, and this teleological view is what many scientists are attacking and may be the loophole in the Gaia hypothesis.

In response to criticisms, the succeeding books about the Gaia theory were buttressed with more scientific findings. Lovelock’s most recent book, The Ages of Gaia: A Biography of Our Living Planet (2000) replies to the criticisms and shows further and recent scientific evidence that proves the truth of his hypothesis (Mills 1990, p. 74) In particular, Lovelock made mention about new studies that linked marine algae, the sulfurs they make and emit, the clouds, and climate, as well as new fields of research, each with their own literature. Lovelock the makes the point that arguments about whether Gaia is right or wrong is moot in the face of the environmental crisis that we are on the threshold of. (Lovelock, 2000, p. 213)

To provide a more compelling picture, Lovelock created Daisyworld, a computer program that simulate a hypothetical world whose sun is increasing in temperature. Daisyworld was created in 1983 in collaboration with Andrew Watson to serves as illustration for the viability of the Gaia hypothesis. The simulated world has two species of daisies, the black and white daisies. The black flowers absorb light while the white flowers reflect them. Over time, the planet no longer suffered from intense fluctuations in temperature. By the increase and decrease in the population of the daisies, the planet was able to regulate its temperature to make it more habitable for both flowers.. The Daisyworld simulation shows that life forms suited to a specific environment have the ability to react and regulate its own environment in ways that make it more hospitable to the organism. The creature does not only adapt to its physical environment, it also has the capacity to effect change in the environment in ways that support and sustain life. (Lovelock, 2000, p. 41)

For much of the 80’s and 90’s the original ideas of the Gaia Hypothesis have endured because much of the scientific proof needed to establish the veracity of the theory requires time. It was only in the late 1990’s until the early twenty-first century did the Gaia Hypothesis evolved. Much like Gaia herself, the Gaia Hypothesis gets better over time. The most recent version of the Gaia Hypothsis can be found in Lynn Margulis’ book, Symbiotic Planet: A New Look at Evolution. Margulis refined the concept of a single organism and went on to define Gaia as a series or units of ecosystems that interact to form one vast ecological system. She makes concessions to criticism yet maintains that certain aspects of the Earth behave like physiological systems in some ways. In so far as there physiological processes were concerned, the earth’s surface may best be described as alive and breathing. (Margulis, 1998) She describes Gaia as symbiosis taken on a grander scale. This more refined and tighter version of the Gaia Hypothesis is now enjoying renewed support from the scientific world, who now regard the theory as provable through empirical data and experiments. Recently Lovelock also made some concessions about his teleological views; that while the Earth tends to act towards order and balance and regulates itself,  the Gaia Hypothesis does not make any claims that this self-regulation is deliberate or planned ahead of time. (Lovelock, 1990)

These changes were reflected in the recent 2^nd Chapman Conference on the Gaia Hypothesis, held on June 2000 at Valencia, Spain. Recent developments in the new field of Bio-geophysiology point to specific and smaller mechanisms where homeostasis is constantly achieved, and each mechanism working towards Gaian homeostasis.  Rather than looking at Gaia from the top-down, scientists are now favoring a more bottom-up approach, where smaller units act as microcosm of the bigger Earth. The recent conference on Gaia explored how geologic records can show proof of the hypothesis.

Among the major issues discussed in this conference was the climatic changes that Gaia underwent over time, and what changes can be expected or extrapolated given this information. Scientists are also looking to the integrity of Gaia’s feedback mechanism, and whether it is strong enough to effect systemic changes in the global climate. Specifically, scientists are looking at which areas are very sensitive indicators of global change and how to prevent catastrophic changes if and when they have started. What can be done to help Gaia protect life and sustain it?

In the end, the Gaia Hypothesis is actually simple in concept: that we are all responsible for our Planet Earth. What we do to our environment creates a cascade of events that eventually goes back to us. This concept of interdependence and collective responsibility challenges us to make radical policy changes in terms of human industries that harm the environment. In politics, the challenge is for politicians to come up with stronger laws that would protect the Earth. This includes the gradual easing up on our independence on oil for energy. Governments must subsidize researches that discover cleaner energy sources and support it with legislation. While this may have some economic repercussions, it is a small sacrifice in light of what is at stake. If we do not take care of the Earth and continue with our wanton destructive ways, then very soon, the Earth will be damaged to such an extent that it can no longer support life. If we protect our environment, we protect ourselves. It does not get much simpler than that.

References

Ford, WD. (1981) ‘Is Nature Really Motherly’. The CoEvolution Quarterly. 58.

Harding, S. From Gaia Theory to Deep Ecology. Retrieved on December 17, 2007 from http://www.adishakti.org/pdf_files/from_gaia_theory_to_deep_ecology_(gn.apc.org).pdf.

Joseph, L. (1990). Gaia: The Growth of an Idea. New York: St. Martin’s Press.

Kellert, S., Osborne, E. (1993). The Biophilia Hypothesis. Island Press.

Lovelock, J. (2000). The Ages of Gaia: A Biography of Our Living Earth. Oxford University Press.

Lovelock, J. (2000). Gaia: A New Look at Life on Earth. Oxford University Press.

Margulis, L., Sagan, D. (1986). Microcosmos: Four Billion Years of Evolution from Our Microbial Ancestors. New York: Summit Books.

Margulis, L., Fester, R. (1991). Symbiosis as a Source of Evolutionary Innovation: Speciation and Morphogenesis. MIT Press.

Margulis, L., (1998). Symbiotic Planet: A New Look at Evolution. Basic Books

Margulis, L., Matthews, C. (2000) Environmental Evolution: Effects of the Origin and Evolution of Life on Planet Earth. MIT Press.

Mills, S. (1990). In Praise of Nature. Island Press.

Russel, P. (2000). ‘The Living Earth’. The Global Brain Awakens. CA: Element.

Samson, P., Pitt, D. (1999). The Biosphere and Noosphere Reader: Global Environment, Society and Change. Routledge.

Schwartzman, D. (1999). Life, Temperature, and the Earth: the Self-Organizing Biosphere. Columbia University Press.

Watson, A. J., (2004). Gaia and observer self-selection. In Scientists debate Gaia: the next century, eds Schneider, S. H., Miller, J. R., Crist, E., and Boston, P. J.  pp. 201-208. MIT press, Cambridge,  Mass, USA.