The idea that the biosphere of Earth is a single organism, whose cells are each of the life forms, and whose bodily fluids are the winds and rain and rivers, is no revelation, though the notion that it is scientifically accurate challenges our idea of an individual organism. The ‘Gaia Hypothesis’ is an attractive theory, since there are many aspects of other life-forms which the earth-as-a-whole shares.
Typically, we think of an individual organism as a single, self-contained entity, which the Earth certainly is. But even we are the combination of trillions of individual, if closely related, life forms; an ecosystem comprised of our cells. Each is one of several hundred classes of cells, all separate aspects of one DNA molecule, living in their own evolved-to-order micro-environment which is created by the other cells.
All life forms do certain things.
If some entity doesn't do all of them, we don’t consider it alive.
Absorption of energy and matter, with subsequent organization of the material, is the first identifying feature of life. Crystals and engines, however, are just two not-living things that can do this.
Death is only possible for life forms. Growth slows down, DNA loses it’s integrity, the old and the weak are lost to predators and disease. Even as part of normal development, most life forms cast off certain cells. Our skin is an example of such normal death. But ‘stopping growth’ equals ‘death’ for crystals or other non-alive things that fit the first part.
Evolution is the process by which life forms change their characteristics over long periods of time, measured in generations. The Earth's biosphere evolves, at least as much as any one life form which lives there. But lots of not-alive things exhibit what might be called evolutionary behavior, since the mechanism is merely the disappearance of unfit things, and the preponderance of fit things: Fit organisms survive. Fit computers are Y2K compliant.
Reproduction is the critical characteristic for any life form to posses, as the replication and distribution of a molecular design code (the DNA, for earthlings) is the crux of what life forms do. Also, our health depends upon the accurate replication of DNA molecules multiple trillions of times, in the cell divisions required for our growth and repair.
Virii do all of the above, but they are somewhat parasitic upon cells, using RNA to reprogram the host cells so they will produce virii instead of important bodily substances. Because virii use RNA instead of DNA, and hijack cells, instead of honorably trying to just eat them, we question whether virii are alive. But humans have been hijacking (domesticating) other life forms for millennia. If the external nature of the virus' ‘food’ is reason to call them non-living, then we are not alive either. And limiting the defintion of 'life form' to DNA alone is merely arbitrary, as the discovery of life on other planets may prove.
By the preceding definitions, Gaia is not a life form. She has not reproduced -- yet.
A bacterium takes twenty minutes to reproduce; A mouse, three weeks; A human being, months. Elephants gestate for two solid years. For all life forms, gestation time is proportional to the size, so we might expect Gaia to take a few billion years.
The resource stress our civilization is experiencing just may be the resource drain on the mother which triggers birth in mammals. We can reasonably expect space based resources to get harvested more as planetary resources get scarcer and hence, more expensive.
The resources of space and our place in it are already a reality.
Space tourism began in 1989, when the first ride was purchased, on the space station Mir.
Communications technology has been completely made over by space-based hardware. It may soon become the primary system. Satellite television, telephone, and weather forecasting systems are just the beginning.
The Moon has water ice. It doesn’t sound like a big deal now, but will probably become the most valuable space resource in our life times, unless some crazy longevity drug is invented.
1996 marked the first year that private space funding exceeded public spending on space exploration, world-wide. Each year, the gap widens.
What’s the major symbol of the environmental movement? An image of Earth from space.
If there are sufficient resources in space, people will one day move there en masse.
We’d have to find efficient ways to lift ourselves off the face of the planet, and find resources in nearly empty, unfamiliar, lifeless regions. We’d experience solar radiation hundreds of times stronger in a fluid thousands of times thinner than home. We’d need new sensory systems, and energy supplies.
And we’ll end up doing the same thing the first amphibians (or last fish) did to meet the same challenges millions of years ago: take our environment with us. It’s no accident that the blood in your veins and water in your eyes are the same salinity as the oceans. Our bodies are ecologies, of sorts; each cell type has evolved to live in the niche created by the rest of our cells, but the basic nature of that ecology is identical to the one within which our cells evolved: the oceans.
The point of all this is that when humans move into space, they will bring their ecology with them, or invent new ecologies. The use of a non-living shell to protect a cell colony from the environment is an old idea. Insects, fish, snakes, and many other life forms use this strategy. Even your teeth take advantage of it. A space capsule is just a cutting edge technology application.
If we accept the notion that Gaia is a life form, then such colonies will be her first children. They will intermingle, and spread, and then isolated systems will evolve away from each other (as they always have) and Gaia will have reproduced, making her fit all the definitions of a life form, using sex organs made of humans.
After all, if it’s us doing it or Gaia, what’s the difference? We are as much of this Earth as anything else grown here.
We don't need to save the planet; we should spread it.