The science and politics of Gaia


By Phil Shannon

NASA probably didn't intend it, but those early space flight pictures of "Spaceship Earth" galvanised an environmental consciousness and movement. As the astronomer Carl Sagan put it, many environmental activists were "stimulated to action by photographs of Earth taken from space, pictures revealing a tiny, delicate and fragile world, exquisitely sensitive to the depredations of man". Many people saw an Earth that needed care and love.

With this vision has come the resurgence of beliefs about the Earth as a living, whole organism, sometimes involving a supernatural Mother Earth figure. Currently, the most prominent theory about a living Earth is the "Gaia" Hypothesis, formulated around 1970 by James Lovelock, the English inventor and geochemist, and then developed by Lovelock and Lynn Margulis (microbiology professor at the University of Massachusetts) during the 1980s.

The Gaia Hypothesis postulates that the Earth's biosphere (that band of air, land and water which contains life) acts as a super-organism with the ability to regulate environmental conditions to sustain itself, in much the same way that the human body's processes maintain the body's water content, temperature, etc at a relatively constant state (homeostasis) to keep the super-organism of the whole body alive. The Earth is one big body, according to Lovelock, and the "planet's homeostasis is maintained by active feedback processes operated automatically and unconsciously by the biota".

The Gaia Hypothesis has attracted much criticism, on two fronts.

Many earth scientists and philosophical materialists have been sceptical, if not contemptuous, of the theory, believing Gaia to be unscientific mysticism.

Many environmentalists and socialists have been critical, often hostile, believing the theory either fosters complacency in the face of environmental damage (because Gaia will cope with all we do to "her"), or flirts with eco-fascism by placing the good of the whole ("Gaia"/Earth) above the rights of its parts (eg, us).

Unwelcome embrace

Of the scientific and political criticisms, the scientific are less of a problem now to Gaia theory. Gaia's early years were unfortunately spent in the embrace of those greens who are motivated by essentially spiritual nature worship.

At a linguistic level, the name "Gaia" was asking for such trouble. "Gaia" was the suggestion of Lovelock's childhood friend and classicist (and Tory) William Golding that he name his theory after the ancient Greek goddess of the Earth. This was a semantic foot in the door for those who attribute physical phenomena to a mystical source, in this case attributing the control and regulation of Earth's biosphere to a supernatural entity or Earth goddess.

Lovelock and Margulis did not intend this interpretation. For Lovelock, "Gaia" was simply a shorthand term, more attractive than his alternative of Biocybernetic Universal System Tendency. In writing for a general readership, said Lovelock, "it has been difficult to avoid talking of Gaia as if she were known to be sentient. This is meant no more seriously than is the appellation 'she' when given to a ship." Margulis was more blunt: "the religious overtones of Gaia make me sick!"

The substance of the Gaia Hypothesis, however, does not warrant a leap from science to mysticism. According to Lovelock, the environment is biologically controlled by "all living matter on Earth, from whales to viruses, from oaks to algae".

Life by luck?

This control by life is the best way to explain Earth's anomalous properties compared to the other planets in our solar system. For example, on the basis of Earth's location between our dead neighbours Venus and Mars (40 million km from Venus with its 477° average surface temperature, and 80 million km from Mars with its surface temperature of -53°), the Earth, argues Lovelock, could be expected to have a surface temperature of about 300°, whereas it is around 13°. Furthermore, this temperature has been maintained over the billions of years of Earth's existence while the sun has grown 30% hotter (enough to boil the water off the planet, as in Venus). Without life's intervention over 3.5 billion years, says Lovelock, an environment hospitable to life would not exist.

The composition of Earth's atmosphere is also anomalous. It is far from chemical equilibrium. An active control mechanism, reasons Lovelock, must be keeping our atmosphere at 79% nitrogen, 21% oxygen, and 0.03% CO2, when we should expect an atmosphere like Venus or Mars, ie 2% nitrogen, 98% CO2 and no oxygen (and therefore no ozone layer), where all gaseous reactions have been played out to chemical entropy. Something is working to keep Earth's atmosphere in chemical disequilibrium. That something, which no other planet has, is life, says Lovelock.

The maintenance by life of these anomalies challenges the conventional view amongst earth scientists that life exists only on Earth simply because of cosmic and geological luck. This is the

so-called "Goldilocks" theory — Venus is too hot, Mars is too cold, but Earth is just right. Not so, says Lovelock. Life evolved, not due to luck but in conditions that life itself maintained by cooperatively carrying out control functions such as ozone formation and oxygen stabilisation.

This collective reaction by life forms to a changing environment, in a manner that ultimately transformed that environment, involved no decision by the biota. No councils of microbes were formed to develop policy. No Earth goddess snapped her fingers.

Gaia's critics, however, charge that the hypothesis is teleological — that is, it invokes a goal-oriented quality from non-conscious life forms. Humans, they argue, are purposive and can consciously alter the environment — not so microbes, algae, trees and rocks.

They claim to have simpler, purely geophysical explanations for the peculiar properties of Earth's atmosphere. They believe that primarily non-biological processes can better explain, for example, Gaia's showpiece, the CO2 thermostat. According to Gaia, CO2 is regulated at a life-maintaining 0.03%, mainly by trees and phytoplankton (tiny plant-like organisms in the oceans). The non-Gaians, however, argue that the carbon-silicate cycle is critical (a geochemical thermostat involving the weathering of rocks, plate tectonics, continental drift and volcanic eruptions).

A "moderate" Gaia position, however, argues that the planet's atmosphere is regulated by a complex of both geological and biological mechanisms. The growing number of "moderates" reflects Gaia's progress from the academic fringe, and from its spiritual dives, to a plausible scientific hypothesis.

Political questions

While the mystical-religious appropriation of the Gaia Hypothesis is illegitimate, Gaia still poses some prickly political questions and is somewhat of an unreliable friend to the green movement.

Gaia shares with other holistic environmental philosophies a view of life as interdependent: humanity is part of, not above, nature, and all our actions affect the planet. Gaia's non-privileging of the human species introduces some needed humility into an anthropocentric world which has pursued the desires of a dangerous, because technologically powerful, human species at the expense of other species and ecosystems (which are also our life-support systems).

Nevertheless, there are problems. Some environmentalists are uneasy with Gaia theory because of Lovelock's view that, because of the resilience of Earth's regulatory processes (Gaia is "tough,

robust and adaptable"), "Gaia"/Earth can withstand the worst we can do to "her"/it.

Lovelock, who discovered the ozone-depleting effect of CFCs in the atmosphere, denied for 15 years that they could do any real damage (and opposed their phasing out) because Gaia would patch up any ozone hole. Lovelock, who has worked for Shell and other multinationals, has friends, and a major source of income, in environmentally harmful industries.

Nuclear power and bombs can not even scratch Gaia, he maintains, supporting nuclear energy. He argues that nuclear energy is both more Gaia friendly and human friendly than coal or oil. When asked his attitude towards a nuclear reactor accident, he replied "Well, I mean it's a good way to go. Even Chernobyl ... was not all that bad." Nuclear war is of some concern — "we might be seriously affected" — but "unicellular life" would not even notice; "Gaia would not care a fourpenny damn". Environmentalists are also misguided to worry about pollution. Life, on a global scale, is safe from our worst efforts.

These views of Lovelock's derive from the Gaian philosophy which judges human actions in terms of their global impact. Lovelock's distinction between "life" and "human life" is often misrepresented by those who delude themselves that Gaia will adjust to permit business as usual. It will not, says Lovelock. Gaia will evolve a new steady state, one that will almost certainly be "less favourable for humans".

As Lynn Margulis puts the Gaia/human distinction — "the idea that we're wrecking the Earth is wrong; but wrecking ourselves is another story". Gaia, despite Lovelock's links to industry, should contain no comfort for apologists for nuclear energy and pollution.

'Weed' control?

Nevertheless, the tension between a Gaian and a human perspective has bedevilled the relationship between Gaia theory and greens. The Gaian implication that the whole is more important than its parts worries many greens, who see Gaia as a form of incipient eco-fascism. Some Gaians, indeed, compare human society to a cancer, a "mammalian weed" (Margulis), a "plague on the planet" (Helen Caldicott).

Although usually attacked with scorn, such strong imagery can be useful for reminding us of the extent of our impact on the Earth. The logic drawn by some, however, is that weeds (even in human form) must be eradicated or controlled. Eradication should horrify us. (Our species has, after all, produced Woody Guthrie and Monty Python as well as thermonuclear bombs and TV quiz shows).

Desire for control of the human "virus" can amount to a bitter cheering on of natural disasters or AIDS as Gaian regulatory responses, or can mean calls for draconian legislation to limit population or consumption.

Michael Fox, the Tasmanian eco-philosopher, calls the charge of eco-fascism a "facile" criticism, arguing that if Gaia has interests and ethical rights, then so do its member species which are wholes within a whole. To adopt a holistic philosophy such as Gaia, he argues, does not require dictatorial politics, but it does set limits to the behaviour of the constituent parts to avoid damaging the whole.

This is a positive interpretation of Gaia, provided the majority of humanity (the workers and oppressed in the species Homo sapiens) have the ultimate say in how those limits are to be set. This would mean revolutionising political and economic structures to enable a democratic, egalitarian and voluntary approach to defining and limiting excessive production, consumption and population.

Gaia is valuable because it reminds us that we are part of a remarkable planet, and that there are limits to our impact on Earth. We are in danger of forgetting that fact. Lovelock, despite his erratic environmental priorities, does at least argue against what he calls the three Cs — "cars, chain-saws, cattle" — for being particularly Gaia (and people) unfriendly. A fourth C — capitalism — needs to be added, so that we can create a world at peace with itself and with nature.