The Gaia Hypothesis is an ecological theory named for Gaia, the Greek Earth Mother Goddess.
It was first scientifically formulated by Dr. James Lovelock, a scientist for NASA who was engaged in studies relating to the search for life on Mars and it was initially published in journal articles in the 70s and popularized by his 1979 book Gaia: A new look at life on Earth
The hypothesis originally developed as a way to explain those chemicals in the atmosphere that could support life in the right combinations and suggested that these combinations would be a way to predict whether life could be supported on another planet. Over time the hypothesis evolved to include many different systems that exist co-dependently and in equilibrium in a self-regulating living system.
Lovelock defines Gaia as:
a complex entity involving the Earth’s biosphere, atmosphere, oceans, and soil; the totality constituting a feedback or cybernetic system which seeks an optimal physical and chemical environment for life on this planet
While this has been a controversial idea, it has held up to a great deal of scientific criticism and has been used to make many successful predictions. Practitioners of spiritual ecology have also embraced it.
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