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Gaia theory

  1. Oct 3, 2006 #1
    http://www.gaiatheory.org" [Broken]

    Do you consider the Earth a living organism?
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Oct 3, 2006 #2
    If it's true then it would dismantle darwinism in a scientific heartbeat... S

    Of course I believe darwinism is on its way out anyway..as do the people at this molecular biology lab:

    http://www.molevol.org/camel/projects/synthesis/ [Broken]

    they seem to have a new view on "evolution" but they don't seem to want Darwin's name in it since it drastically reduces the role of natural selection by way of nonrandom variation. Molecular biology is revolting against neo-darwinism and is threatning to overthrow the whole theory. It's getting interesting in the world of biology/evolution.
    Last edited by a moderator: May 2, 2017
  4. Oct 4, 2006 #3


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    I find the idea somewhat usefull as a model, but I don't take it litterally, myself. If you use it as a metaphore, it puts a lot of things into clearer perspective. I do think that those who like to refer to the Great Barrier Reef as "the worlds largest living organism" are proven wrong by this theory. If we're going to call all those seperate organisms one big organism, just because they interact intimately with one another, then we have to include the rest of the planet as well.

    Unfortunately, this model makes mankind the reproductive organs, since we will almost certainly be the first species on the planet to carry itself off-world and start a new organism (or "planetism", as some like to call it). With the beginning of the space program, earth reached reproductive maturity, and when colonisation and eventually Terraforming begin, we will have begun the perpetuation of the species.

    Once we fill the whole Gallaxy, I suppose we'll start seeing it as an organism (gallactism?), untill we spread out over the whole of the reachable universe, forming a cosmism.

    But in the final annalisys, I can't consider the rain forest or the Everglades or the whole planet one big organism in any litteral sense. I think it generalises the meaning of the word to such a degree as to render it useless, making "organism" mean, basically, "whatever you want it to mean".
  5. Mar 15, 2007 #4
    Right, i can't consider the planet as a living organism. It is more acceptable like a system.

    But the theory itself seems to be very useful if applied to other things.
  6. Mar 15, 2007 #5
    I also agree that it's good as a metaphor but doesn't hold up in reality, it's self contradictory:

    you could say that what is "alive" is somewhat debatable, but most of us can agree on some basic prerequisites (organization, metabolism, reproduction... etc.).

    the earth would seem to qualify for all of the prerequisites -- except for reproduction... but, as lurch said, if humans (or any organism) ever started populating other planets and transforming them into earth-like systems, some would argue that that could be seen as a sort of reproduction.

    but does this mean that the earth itself is alive? ... not really, what's reproducing is not the earth itself, but rather the system of life.. a better metaphor would be viral activity, not cellular (if life is earth's metaphoric DNA, that DNA is implanting itself on another host planet) -- this isn't reproduction of earth, it's the reproduction of the system life; life is alive to begin with! lol, it kind of cancels itself out....

    so if someone argues that earth is alive, I would say that it lies more in the same gray area as a virus (metaphorically)
    Last edited: Mar 15, 2007
  7. Mar 15, 2007 #6


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    Isn't Gaia just regular climatology and ecology with "And therefore the earth is alive." tacked on to the end?
  8. Mar 15, 2007 #7

    jim mcnamara

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    It's more like: the earth is a self modifying entity, constanlty modifed by living things to maintain an equilibrium that favors their existence.

    Oxygen<->Carbon Dioxide levels are often cited, as are higher/lower levels of atmospheric oxygen in Carboniferous/Permian times for example.
  9. Mar 15, 2007 #8


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    I thought that normal climatology and ecology already acknowledged complex feedback systems of that nature. Maybe I'm misunderstanding something.
  10. Mar 15, 2007 #9

    jim mcnamara

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    Gaia predates modern climatology.
  11. Mar 15, 2007 #10
    See Wikipedia for good overview:

    Here is the original definition of 'Gaia' presented by James Lovelock:

    Lovelock defined 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".

    Note, the original definition of Gaia does not use the word "organism"--it uses the word "entity". Important difference, for while all organisms are entities, not all entities are organisms.

    We see that Gaia (G) is an "cybernetic" entity (the Earth) with 4 interacting systems (each with many sub-systems, etc.):

    (1) biosphere
    (2) atmosphere
    (3) oceans
    (4) soil

    But Gaia is a unique cybernetic entity having a single goal or purpose--it "seeks" for something. When it is said that an entity "seeks" for some"thing", it does not mean that the entity will find that "thing". Neither does it mean that a "seeker" must always be alive. Robots "seek" for things, your computer search engine (i.e., Google) seeks for things. Therefore, by definition provided by its founder--Lovelock--the Gaia may be alive or may not be alive, thus by definition it cannot be an organism for the simple reason that no organism (unlike the Gaia) may be not-alive.

    See that from Lovelock definition the Gaia seeks for the "physical and chemical" good of "the other" (what Lovelock calls "life")--thus Gaia is a warm fuzzy o:) altruistic entity--seeking the good for "life itself". Makes one think Gaia not too happy with Homo sapiens --so much chemical pollution from one of Gaia's children making Gaia work so much harder as a cybernetic regulator.

    I conclude the reason for being of Gaia is to replace concept of God in mind of Lovelock.
  12. Mar 15, 2007 #11
    Gaia seems to be at one end of the life spectrum, where prions and viruses are at the other end. They all represent potential life and its limitations.

    How about space (e. g., the Sun or panspermia) being a fifth system?
  13. Mar 19, 2007 #12
    I think Lovelock views "space" (Sun, Moon, etc.) being "outside" the Gaia as a cybernetic system. Space thus a "forcing function". To understand how Lovelock views Gaia one must understand constraints of "cybernetic systems", because where constraint exists one can take advantage of it, and Lovelock good at taking advantage of Gaia concept to serve as token for God concept, at least this is how I see it. If Lovelock does view Gaia as a "living" cybernetic entity (and not an entity that "seeks" good for other forms of life), then Gaia the most complex pure selfish entity I know, for it then "seeks" the good for itself. But because I think this idea is contrary to thinking of Lovelock, that is, Lovelock views Gaia as a warm fuzzy altruistic entity looking after living entities that exist on-within it, for this reason I think Gaia takes place of God concept in mind of Lovelock. I would be very interested in knowing if Lovelock views God as creating Gaia, Gaia creating God, or neither.
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