Propounded by James Lovelock in the 1960s, Gaia Theory is a startlingly new way of looking at the earth. When viewed from space, the earth looks like a pulsating and swirling blue sphere, and this vision possibly gave Lovelock the inspiration to visualise the earth as a single living being. Named after the Greek goddess ‘Gaia’, the theory asserts that all organic and inorganic matter on and around the earth emerge from a common cosmic womb. All such matter has evolved over time to form an intricate web of systems and sub-systems. These systems are intrinsically inter-connected to form a super organism, naturally programmed for self regulation.
 A Living System
The Gaia Theory suggests that this living system has automatically controlled global temperature, atmospheric content, ocean salinity and other factors in order to preserve its own survival. This system can be likened to any individual organism that unconsciously regulates body temperature, blood salinity, etc. So, for instance, even though the luminosity of the sun has increased by about 30 per cent since life began almost four billion years ago, the living system has reacted as a whole to maintain temperatures at levels suitable for life.
This idea of the earth as a living being is initially difficult to accept. With strides in observation techniques, it has become easy for us to accept even micro-organisms not visible to naked eyes as ‘living’, but when it comes to the whole planet, it's naturally difficult to comprehend the concept. It seems that an inanimate object such as the earth, which is almost wholly comprised of non-living components such as rocks and water, can not be living.
A beautiful analogy to explain this concept can be found in the image of a giant Redwood tree. The tree is undoubtedly alive, yet you might not be aware that 99 per cent of it is dead! The great tree, and especially its bark, primarily comprises dead cells that are remnants of once living cells, and these dead cells form a protective covering on the tree to account for its longevity. This is very much like the earth, where most of the rock formations were once living organic matter.
 Need to Protect the Gaia
It would be quite natural for us to think that if Gaia is a self-preserving entity, we as human beings are absolved of our responsibility towards preservation and conservation of this system. True, Gaia naturally protects her equilibrium and is herself probably not endangered by the depredations of the human species; rather, the danger is to the human race.
Gaia shelters life in general — not any particular form of life. Since her inception, she has witnessed mass extinctions of animals such as dinosaurs and ammonites. But Gaia survived and merely replaced the extinct life forms by evolving new life forms better adapted and suited to the larger good of the whole system.
Human beings, due to the havoc they are wreaking on eco-systems and bio-diversity can be equated to a gangrenous limb, which the Gaia may feel compelled to amputate. Ever since the invention of agriculture, we have been interfering in the natural processes of Gaia. About half a century ago, we began using chlorofluorocarbons, which have been destroying the protective ozone layer. Even more drastic, we are disrupting Gaia's mechanisms for temperature control — especially the levels of carbon dioxide and methane in the atmosphere. Projections by international environmental agencies on climate change suggest that global temperatures may rise considerably by the end of the next century given present trends.
The writing on the wall is clear. Poles are melting, there is an increase in ocean and sea levels, ecological zones are shifting and rainfall patterns have become erratic. These ominous signs could be seen as preparations of the Gaia to catastrophically deal with the disease called humans.
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