The Modern Gaia Theory

What is Gaia Theory? Stated simply, the idea is that we may have discovered a kind of living being bigger, more ancient, and more complex than anything from our wildest dreams. and that that being, called Gaia, includes all the others on our planet.

More precisely: that about one billion years after it's formation, our planet was occupied by a meta-life form which began an ongoing process of transforming this planet into its own substance. All the life forms of the planet are part of Gaia. In a way analogous to the myriad different cell colonies which make up our organs and bodies, the life forms of earth in their diversity coevolve and contribute interactively to produce and sustain the optimal conditions for the growth and prosperity not so much of hemselves, but of the larger whole, Gaia. That the very makeup of the atmosphere, seas, and terrestrial crust is the result of radical interventions carried out by Gaia through the evolving diversity of living creatures.

Encountering the Earth from space, a witness would know immediately that the planet was alive. The atmosphere would give it away. The atmospheric compositions of our sister planets, venus and mars, are: 95-96% carbon dioxide, 3-4% nitrogen, with traces of oxygen, argon and methane. The earth's atmosphere at present is 79% nitrogen, 21% oxygen with traces of carbon dioxide, methane and argon. The difference is Gaia, which transforms the outer layer of the planet into environments suitable to its further growth. For example, bacteria and photosynthetic algae began some 2.8 billions of years ago extracting the carbon dioxide and releasing oxygen into the atmosphere, setting the stage for larger and more energetic creatures powered by combustion, including, ultimately, ourselves.

That is how James Lovelock discovered Gaia; from outer space.
In the 1960's, during the space race which followed the launching of Sputnik, he was asked by the Jet Propulsion Laboratory and Nasa to help design experiments to detect life on Mars.The Viking lander gathered and tested some Martian soil for life with no results. Lovelock had predicted as much, by analyzing the atmosphere of Mars: it is in a dead equilibrium. By contrast, the atmosphere of Earth is in a "far from equilibrium" state- meaning that there was some other complex process going on which maintained such an unlikely balance. It occurred to him that if the Viking lander had landed on the frozen waste of antarctica, it might not have found any trace of life on Earth either. But a sure giveaway would be a complete atmospheric analysis... which the Viking lander was not equipped to do. Lovelock's approach was not popular at Nasa because Nasa needed a good reason to land on Mars, and the best was to look for life. Viking found nothing on Mars, but Lovelock had seen the Earth from the perspective of an ET looking for evidence of life. And he began thinking that what he was seeing was not so much a planet adorned with diverse life forms, but a planet transfigured and transformed by a self-evolving and self-regulating living system. By the nature of its activity it seemed to qualify as a living being. He named that being Gaia, after the Greek goddess which drew the living world forth from Chaos.

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