The Gaia Hypothesis

The Earth2 series is an exemplar of popularized manifestations of a controversial biochemical theory provocatively named by its originator the Gaia Hypothesis. A British biochemist, James Lovelock, formulated the theory while working with NASA's space program, looking for ways to detect life on Mars. The crux of his theory is that living organisms and inorganic material are part of a dynamic system that shape Earth's biosphere. The earth is a self-regulating environment and the planet itself is the core of a single, unified, cooperating and living system -- a superorganism that regulates physical conditions to keep the environment hospitable for lifeforms[1]
Gaia theory is about the evolution of a tightly coupled system whose constituents are the biota and their material environment, which comprises the atmosphere, the oceans, and the surface rocks. Self-regulation of important properties, such as climate and chemical composition, is seen as a consequence of this evolutionary process. Like living organisms and many closed-loop self-regulating systems, it would be expected to show emergent properties; that is, the whole will be more than the sum of its parts.[2]

American microbiologist Lynn Margulis has been Lovelock's principal collaborator for twenty-five years. She is an expert on the role that microorganisms play in evolution. Margulis contends that symbiosis, not chance mutation, is the driving force behind evolution and that the cooperation between organisms and the environment are the chief agents of natural selection -- not competition among individuals.[3] She says that "Darwin's grand vision was not wrong, only incomplete.[4]
In accentuating the direct competition between individuals for resources as the primary selection mechanism Darwin (and especially his followers) created the impression that the environment was simply a static arena for "nature, red in tooth and claw (Tennyson, 1850).[5]

These two fundamental components of Lovelock and Margulis's Gaia theory --- that the planet is, in Margulis's words, a "super organismic system"[6] and that evolution is the result of cooperative not competitive processes -- find repeated expression in Earth2.

Earth 2: A Gaian Hypothesis homepage