Gaia Hypothesis

This is the notion that "the surface of the earth behaves as a highly integrated organism capable of controlling its own composition and its environment." This suggests that the Earth is analogous to a single, highly complex organism with numerous sub-systems and feedback loops.

A justification for this hypothesis is that the composition of the earth's atmosphere would be radically different if there were not life on the surface. Without flora and fauna, the atmosphere would be mostly CO2, with very little nitrogen or oxygen. However, with the addition of life, in combination with the Earth's other subsystems, the Earth's various aspects constitute a feedback system that seeks an optimal environment to sustain life.(Eblen and Eblen, 1994, p. 289)

Compiled by

Alex Ogilvie amo2@cec.wustl.edu Last updated 10/26/94.