Origins of Gaia Theory

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This page suggests how James Lovelock got to the Gaia concept. We are indebted to another site for this preliminary statement.

Setting the conditions for life

In the search for the evidence of extra-terrestrial life, the closer - Earth's neighbouring planets - Venus and Mars were targetted by the NASA program. Of these, due to the unknown conditions of the planetary surface caused by the dense and aggitated Venusian atmosphere, the planet Mars was given priority. The first spacecraft to visit Mars was Mariner 4 in 1965, and several others followed including the two Viking landers in 1976.

Dr James Lovelock, a British Chemist specialising in the atmospheric sciences, was a recognised leader in his field. He was to invent an electron capture detector, capable of tracing extremely small amounts of tracer elements in gases, which was used by the ozone monitoring research concerning the effect of CFC's in the early 1970's. Almost a decade before this, NASA and the Jet Propulsion Laboratory (JPL) requested the presence of Lovelock in their project teams relating to the scientific search for the evidence of life on Mars.

In collaboration with other project researchers, Lovelock predicted the absence of life on mars based on the consideration of the Martian atmosphere and its state of being in a chemically dead equilibrium. In contrast, the Terran atmosphere is in a chemical state described as being far from equilibrium. The unlikely balance of atmospheric gases which comprise the Earth's atmosphere is quite unique in our solar system. This fact would be clearly visible to any extra-terrestrial observer, by comparison of the images of the planets Venus, Earth and Mars.

The Oxygen Atmosphere

The most important change in Earth's environment since life began is the buildup of free oxygen in the air. Before life became established on Earth, the air contained no free oxygen. Today, the atmosphere is 21 percent oxygen. Although small amounts of oxygen were present very soon after life appeared, the significant buildup probably began about two billion years ago. By the time of the Cambrian Explosion, 570 million years ago, the oxygen content had to be approximately as high as it is today.

There is evidence that the beginning of the oxygen buildup coincides with the appearance of the first eukaryotic cells. Most bacteria don't require oxygen, and many are poisoned by oxygen. All eukaryotic cells require oxygen for their more complicated and more efficient metabolism. Furthermore, there has to be oxygen for there to be ozone. Ozone shields the surface of Earth from damaging ultraviolet rays. Only with such shielding can life come out from under the water and begin to live on land.

"It is widely believed that 2000 million years ago the cyanobacteria—oxygen eliminating photosynthetic prokaryotes that used to be called blue-green algae...—effected one of the greatest changes this planet has ever known: the increase in concentration of atmospheric oxygen from far less than 1% to about 20%. Without this concentration of oxygen, people and other animals would have never evolved"

The question which Dr James Lovelock obviously asked himself was ...
WHY was the Earth different?

Research concerning the chemical analysis of the composition of the Venusian atmosphere has yielded figures of 95-96% carbon dioxide, 3-4% nitrogen, with traces of oxygen, argon and methane. The same analysis for Mars returns 95.3% carbon dioxide, 2.7% nitrogen, 1.6% argon, only 0.15% oxygen and only 0.03% water. In comparison the Earth's atmosphere at present is 77% nitrogen, 21% oxygen with traces of carbon dioxide, methane and argon.

What was happening upon the Earth which enabled the maintenance of such an unlikely combination of chemical gases - specifically nitrogen and oxygen. What complex processes are at work within the terrestrial atmosphere - and have occurred for many billions of years - to explain this uniqueness? How have these processes arisen and what today maintains these processes at this equilibrium which is chemically far from equilibrium?

How the Gaia Hypothesis was so named ...

So it was then that Dr James Lovelock, in looking for the evidence of extra-terrestrial life on Mars, observed the Earth as might an extra-terrestrial, and began to formulate a method of explanation as to why the Earth appeared therefore to be not so much a planet adorned with diverse life forms, but a planet which had been transfigured and transformed by a self-evolving and self-regulating living system. In view of the nature of this activity, Earth seemed to qualify as a living being its own right. And so the hypothesis took its initial form.

And as the story goes, while on a walk in the countryside about his home in Wiltshire, England, Lovelock described his hypothesis to his neighbour William Golding (the novelist - eg: Lord of the Flies), and asked advice concerning a suitable name for it.The resultant term "Gaia" - after the Greek goddess who drew the living world forth from Chaos - was chosen.

Thus the Gaia Hypothesis was first postulated.

However, there was a big difference between postulating such a grand schemed hypothesis and having it accepted by the traditional scientific community, and there remained much research work to be done in order to be able to more clearly specify the entirety of the processes by which the modern planetary atmosphere had been evolved and was continuing to be evolved. And in this task, in the early years of his further research concerning the Gaia hypothesis, Lovelock was supported by the collaboration of Dr Lynn Margulis, a leading and forward thinking American microbiologist.

Gaia: A New Look at Life on Earth - [1979]

By 1979 James Lovelock had published some of his ideas in a first book "Gaia: A New Look at Life on Earth" in which the statement of the specification of the Gaia Hypothesis had become somewhat better defined. In this book we find him putting forward the postulate:

'...the physical and chemical condition of the surface of the Earth, of the atmosphere, and of the oceans has been and is actively made fit and comfortable by the presence of life itself. This is in contrast to the conventional wisdom which held that life adapted to the planetary conditions as it and they evolved their separate ways.''

"The entire range of living matter on Earth from whales to viruses and from oaks to algae could be regarded as constituting a single living entity capable of maintaining the Earth's atmosphere to suit its overall needs and endowed with faculties and powers far beyond those of its constituent parts...[Gaia can be defined] as a complex entity involving the Earth's biosphere, atmosphere, oceans, and soil; the totality constituting a feedback of cybernetic systems which seeks an optimal physical and chemical environment for life on this planet."

"To what extent is our collective intelligence also a part of Gaia? Do we as a species constitute a Gaian nervous system and a brain which can consciously anticipate environmental changes?" [p147]

The Gaia Hypothesis has often been described by commentators as one of the most provoking singular ideas to have been put forward in the second half of the 20th century, and while it struggled to be formally accepted in the fields of the traditional sciences in the 1970's and early 1980's, it certainly managed to provoke its share of debate. During this period, Lovelock prepared for a second publication.

The Ages of Gaia:[1988] A Biography of Our Living Earth

Almost a decade after having the first book prepared, and almost twenty years since initially considering the nature of the living systems which are clearly in evidence in operation within the terrestrial ecosystems, Lovelock had published a second book, entitled "The Ages of Gaia". In this we find - naturally enough - that the presentation of his ideas are more mature, researched and informed. Moreover, the interconnectedness of the all the natural terrestrial systems - not just the atmosphere - was beginning to emerge in his consideration of those original questions.

We see Lovelock evolving and refining the specification of the nature of Gaia:

"The name of the living planet, Gaia, is not a synonym for the biosphere - that part of the Earth where living things are seen normally to exist. Still less is Gaia the same as the biota, which is simply the collection of all individual living organisms. The biota and the biosphere taken together form a part but not all of Gaia. Just as the shell is part of the snail, so the rocks, the air, and the oceans are part of Gaia. Gaia, as we shall see, has continuity with the past back to the origins of life, and in the future as long as life persists. Gaia, as a total planetary being, has properties that are not necesarily discernable by just knowing individual species or populations of organisms living together

... Specifically, the Gaia hypothesis says that the temperature, oxidation, state, acidity, and certain aspects of the rocks and waters are kept constant, and that this homeostasis is maintained by active feedback processes operated automatically and unconsciously by the biota."

Lovelock goes on to say ...

"You may find it hard to swallow the notion that anything as large and apparently inanimate as the Earth is alive. Surely, you may say, the Earth is almost wholly rock, and nearly all incandescent with heat. The difficulty can be lessened if you let the image of a giant redwood tree enter your mind.The tree undoubtedly is alive, yet 99% of it is dead.The great tree is an ancient spire of dead wood, made of lignin and cellulose by the ancestors of the thin layer of living cells which constitute its bark. How like the Earth, and more so when we realize that many of the atoms of the rocks far down into the magma were once part of the ancestral life of which we all have come."

While the scientific communities continued to debate the level of acceptablity of the Gaia Hypothesis, the global and holistic perspective of the concept continued to capture the imagination of people from all walks of life. The indigenous cultures who saw the nature of earth as a sacred spirit, others who sought the "oneness" in nature, those concerned for the environment - the trees, the rivers and the oceans, and those seeking contentious and revolutionary ideas, and those seeking religious frameworks - to an increasing multicultural and multidisciplined audience the concept of the Gaia Hypothesis was nourished and supported as a New Age paradigm.

Multicellular Red Herrings flourished in the primordial seas of Gaian debate during the 1970's and 1980's [and of course still do to a large extent] and while the non-scientific applicability of the concept flourished far and wide, they tended to very much to reduce the concentration upon the primary scientific issues of the hypothesis, its analyses and the implications of these.

Largely however, these misundertandings were unavoidable in the initial statements of the specification of the hypothesis due to its intrinsic holistic nature and the scope of the global concept which it attempted to portray. Moreover, what was becoming clearer was that the concept had applicability to many disciplines and to many inter-disciplinary issues. The problem was in being specific.

Skeptics had argued (and still do) that this Gaia was teleological - that it supposed the evidence of some design or purpose in the nature of the biosphere - in particular the adminsitration thereof - and that this was contra to the accepted position of Darwinian evolutionary doctrine which supported natural selection. Dr Lynn Margulis had much to reply in this area regarding the systematics of Darwinian evolution in regard to the smallest and earliest of living things upon the earth. Yet in his research and in the above publication, Lovelock countered this argument with ecological considerations:

"Theoretical ecology is enlarged. By taking the species and their physical environment together as a single system, we can, for the first time, build ecological models that are mathematically stable and yet include large numbers of competing species. In these models increased diversity among the species leads to better regulation."

And then later, elsewhere in the Ages of Gaia ...

"When the activity of an organism favors the environment as well as the organism itself, then its spread will be assisted; eventually the organism and the environmental change associated with it will become global in extent. The reverse is also true, and any species that adversely affects the environment is doomed; but life goes on."

But perhaps the most popularly known counter-argument employed by Lovelock at this time (in fact in 1983) was the systematic behaviour of the theoretical planet of Daisyworld which, like the earth, maintained its global temperature reasonably constant in the face of time and the increasing energy output of its sun.

The traditional physical earth sciences of geology, oceanography, meteorology and geography had beforehand never seriously considered or analysed the complex nature of the ecological systems abounding in their respective domains and cross-domain systems. However it is interesting to note that James Lovelock and Lynn Margulis acknowledge the geologist-physician James Hutton's concept of a living Earth as a forerunner to the Gaia hypothesis.

In fact, James Hutton (1727–1797), often considered to be the father of modern geoscience, authored the concept of the rock cycle, which depicts the interrelationships between igneous, sedimentary, and metamorphic rocks. The upper part of the earth (mantle, crust and surface) can be envisioned as a giant recycling machine; matter that makes up rocks is neither created nor destroyed, but is redistributed and transformed from one rock type to another. It was Hutton who suggested that the proper study of the Earth should be by "geophysiology".

Just as human physiology can be viewed as a system of interacting components (nervous, pulmonary, circulatory, endocrine systems, etc), so too can the Earth be understood as a system of four principal components (atmosphere, biosphere, geosphere, and hydrosphere). Thus we find this more holistic approach the Gaian specification being made by Lovelock's use of this term "geophysiology" for the investigations of Earth, life and ecological science. As with human physiology, it emphasizes its biological base, the perspective of the whole system, and an interest in systemic health.

In the same year (1988) that this second book was published, the debates concerning the Gaia Hypothesis within the scientific community were still in full swing, and it was therefore decided to hold a symposium in relation to this matter, at which various scientists had the opportunity of presenting papers. The collective information presented at this meeting was - three years later - to become the substance of the third book concerning the Gaia Hypothesis to which Dr James Lovelock had contributed.