ABSTRACT
The Gaia theory of James Lovelock and Lynn Margulis uses a controversial mechanism to explain the chemistry of the atmosphere, hydrosphere, and lithosphere of earth, which is unique in the sense that earth is the only planet known to have life. The theory suggests that organisms are intricately involved in both producing and regulating the liveability of earth's surface. It is proposed that the mechanism is comprised of networks of feedback loops, any one of which might operate in a manner comparable to a household thermostat. The cycles of some feedback loops might tend to damp one another out while some might enhance each other. In the case of the Gaia hypothesis, the thermostats are organisms and their sensitivities to environmental conditions are very basic. That is, in some environments organisms will leave more offspring than in others as a result of natural selection.
