I’ve just finished reading the 1979 book Gaia: A New Look At Life On Earth by James Lovelock. It’s a good read and I’d highly recommend it, even if it may be a bit outdated. In it, Lovelock sets out a summary of his ‘Gaia’ theory, a theory of the ‘Organic Earth’. He visualises life across the planet as, although existing in an array of individual life forms, comprising something greater – a bit like how cells and bacteria in our bodies come together to comprise us. His evidence and conjecture really are fascinating; he uses the improbable stability of the atmosphere as evidence, for instance, with there being an optimal level of oxygen to support life but not so much that there’s a danger of flammability. This is an easier example to understand how Gaia works: if the oxygen level gets too high then forest fires would begin breaking out, adding carbon dioxide to the air and also limiting oxygen produced by plants. If it gets too low in favour of carbon dioxide then plants will prosper, thereby creating an increase of oxygen into the air. He also discusses the implications of human civilisation on Gaia.
I’m interested at the extent to which his ideas have entered the scientific mainstream opinion. Lovelock clearly wrote Gaia knowing that parts of it would be perceived as a radical new idea, yet, much of it is familiar to things I recall learning at school. I can’t name any specifics but the general concept of all life on Earth existing in a mutually-dependent relationship is one which seems obvious to me as a result of my education. Has the consensus changed that much in just 30 years? There are other things I noticed that have changed, such as successful steps taken to limit the emission of CFCs to save the ozone layer from depletion (a remarkable feat, in retrospect) which was only beginning when Lovelock wrote the book. It’s now accepted that this action was well-judged and may have saved us from terrible consequences.
One thing which hasn’t changed is the debate over fossil fuels. Lovelock seems to hold the position that they are not as great a problem as is often claimed (he even considers whether activities on land could ever truly threaten Gaia as long as the oceans are left intact; I disagree, though his example of the destruction Ice Ages cause is convincing). He is outspoken in his opposition to renewable energy and even seems in favour of using fossil fuels which is, uh, a strange position for an ecologist to take. To be fair, Lovelock aside, most scientists are in agreement that the use fossil fuels ought to be limited – it’s largely the public which still grasp on to outdated ideas.
Another idea I found fascinating was Lovelock’s speculation on the ‘purpose’ of humanity for Gaia. Unlike evolution within a species, changes to Gaia don’t seem to necessarily require being advantageous to it so it’s possible that humanity could simply be an ‘accident’, but it’s interesting to speculate nonetheless. He wondered whether an intelligent species (intelligence defined as having the ability to store information collectively and add to it throughout successive generations) might act as a kind of guardian of Gaia. He pointed to a hypothetical asteroid collision with Earth, which in normal circumstances would be a catastrophe for life on Earth. Humanity’s presence, however, through our development of technology might actually be able to stop this threat to Gaia. It’s certainly a challenge to the accepted view that humans are nothing more than a cancer to the planet – though Lovelock does warn of the dangers human overpopulation might have for Gaia.
Despite being out of date in places and even despite disagreeing with bits of it, Gaia is still a book well worth reading. You’ll need a basic understanding of chemistry and biology to understand everything but it is generally written in a readable and often quite poetic style.