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According to Wikipedia, "all known types of organism are capable of some degree of response to stimuli, reproduction, growth and development and self-regulation via homeostasis." Further, watching a video like the "Earth Breathes as Seasons Change" (which is from NASA) - superficially gives the sense that the "Earth is alive" so to speak.

Is Earth an organism? Since there is no unequivocal definition of life, the current understanding is descriptive. To define Earth as an organism, your answer most show either via observed phenomena or theoretically observable phenomena that Earth exhibits all or most of the following traits: Homeostasis, Organization, Metabolism, Growth, Adaptation, Response to stimuli, and Reproduction.

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    $\begingroup$ A label is just a name. Anybody can name the Earth how they want. Do you perhaps mean a model? $\endgroup$
    – gerrit ♦
    Apr 26, 2014 at 2:59
  • $\begingroup$ Review aspects of Upper-atmospheric lightning, Schumann resonances and various upper-atmospheric phenomena, and try to imagine that region as a kind of cerebral cortex of a planetary-scale nervous system and the phenomena as nervous discharges. We might learn to "communicate" with the Earth as a very long-lived, slow-living 'organism' someday. "It's alive!" $\endgroup$
    – user2338816
    Apr 26, 2014 at 3:24
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    $\begingroup$ my main issue with this question is that it seems purely philosophical to me: let say you can label it as an organism, will that bring anything to our understanding of earth? or our understanding of organisms for that matter? $\endgroup$
    – plannapus
    Apr 26, 2014 at 15:00
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    $\begingroup$ The Earth is somewhat like an organism, in the sense of the Gaia hypothesis. But you seem to be asking "is the Earth literally an organism", in the same way that cows and trees and bacteria are organisms. The only reasonable answer to this is "no, obviously not." It's like asking "is the Sun a coffee cup?" You don't think it is, nobody else thinks it is, and nobody sane ever said it was - so what's the point of the question? $\endgroup$
    – N. Virgo
    May 4, 2014 at 7:00
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    $\begingroup$ -1. As has been noted there is no clear definition of life, so there can be no clear answer to this question (except perhaps the common sense one of "of course not!"). As such this is asking for opinions, and is off-topic. And also, frankly, it's more about philosophy than earth science, and is thus doubly off-topic. $\endgroup$
    – Semidiurnal Simon
    May 5, 2014 at 20:05

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[I am going to preface this by saying that I am not in one camp or the other in this discussion, as I think there are pros and cons to each side]

This links to the "Gaia Theory" proposed by James Lovelock, wherein the Earth is considered a self regulating organism.

In this hypothesis, Earth is an organism in that it will try to maintain certain conditions. These conditions include temperature (within a range suitable for life as we currently understand it), oxygen content of the atmosphere, water availability etc.

This does not mean that the ball of rock we are flying through space on is a living organism as we understand it, but rather that the various spheres of life (These are usually the biosphere (ecosystems), the atmosphere, the cryosphere (the poles, and other ice-bound areas), the hydrosphere(oceans), and the pedosphere(soil)) interact with each other in such a way that optimal conditions are maintained.

Whilst the theory as a whole is not used today, it is recognised that feedbacks and interactions between different spheres occur, and are an important part of understanding Earth systems, and is studied in an area of science known as Earth System Science

One of the initial arguments for this theory was that our atmosphere is not in chemical equilibrium, and that there must therefore be processes active to maintain oxygen levels at a steady state outside of equilibrium.

This is a difficult topic, as it is important to stress that the Gaia hypothesis does not state the Earth is some sentient being consciously doing anything, rather that a complex set of interactions, abiotic and biotic, combine to maintain and regulate the planets temperature and atmospheric composition.

An example of this regulation is chemical weathering, whereby carbon dioxide in the atmosphere falls in rain, and reacts with rocks, to form calcium bicarbonate, removing carbon from the short term carbon cycles. The more surface rocks there are which are capable of this reaction, the more CO2 is removed from the atmosphere. There is a hypothesis which says that at least once, the Earth has been covered largely in ice and snow, and this reaction (known as carbonation) is suspected to have played a part in the recovery of Earth. The hypothesis (Snowball Earth) goes like this:

The Earth became cooler, whether due to Milankovich cycles, volcanic activity, or solar output changes. As this happened, ice began to form at the poles, changing the albedo, and reflecting more radiation back to space, this caused local cooling, and allowed for the growth of the ice sheets. As they spread, the albedo became higher on a larger scale, and the ice sheets eventually covered the two hemispheres, with a band of open ocean at the equator. The earth was now very cold, but not completely empty of life, or without volcanic activity. Life continued to respire CO2, and volcanoes continued releasing CO2. Without rocks to remove it from rain, or ocean to absorb it, Carbon dioxide began to build up in the atmosphere. As it built up (over millions of years), it began to warm the planet, which in turn began to melt the snow. As the snow and ice began to retreat to the poles, rocks, and open ocean were again available to remove the carbon dioxide from the atmosphere, and more photosynthetic organisms were able to survive, and remove more CO2 through photosynthesis.

This lead to a stabilisation of the planets systems again, although, it may have gone too far, and swung back to a glacial period (although not a frozen earth), then moving back to a warm period before stabilising due to the tectonic movement of the continents northwards The break-up of Rodinia, birth of Gondwana, true polar wander and the snowball Earth

I hope this long ramble illustrates how there are a number of complex systems which all interact with each other to maintain conditions. Whether we consider the sum of these systems an organism is an ongoing discussion, but, all organisms have the ability to regulate via various systems, and each of these systems has the potential to lead to chaotic positive feedbacks, and spiral out of control, although negative feedbacks usually keep everything running as normal.

I have linked the Gaia theory webpage, and if you search for Daisyworld model, you will find a model which you can run to simulate feedbacks It is up to you whether you think this collection of feedback systems is an organism, and this debate will likely run for decades more.

Gaia Theory Site

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    $\begingroup$ The gaia hypthosis says that the earth is a complex self regulating organism, it does not reproduce, no. $\endgroup$
    – Rhiaden
    Apr 26, 2014 at 15:24
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    $\begingroup$ If Earth does not reproduce, it is not an organism. In my opinion, there's no need to post an answer about the gaia hypothesis, since it does not answer the question; meaning the gaia hypothesis does not claim that the Earth is an organism. In fact, there's no reference at all in your answer as it relates to means of observing and classifying the reproductive behavior of Earth, right? $\endgroup$
    – blunders
    Apr 26, 2014 at 15:30
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    $\begingroup$ you could be a little more positive about it: you asked a frankly peculiar question and Rhiaden took the time to give you a detailed, interesting answer that (as you feel, and it's your right) doesn't cover everything (because honestly how are you supposed to bring contradictory evidences to such an extraordinary claim as the reproduction of Earth) but is totally relevant (i honestly thought you were querying about the Gaia theory as well, after reading your question). I think it's a little unfair to shun him down, when you could have just said "thanks but what about the reproduction aspect?". $\endgroup$
    – plannapus
    Apr 26, 2014 at 16:36
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    $\begingroup$ @SlippD.Thompson: Thanks, though unable to find anything to support that "there's little condemnation on SE for off-topic answers" - have any supporting links on the topic? $\endgroup$
    – blunders
    Apr 27, 2014 at 1:40
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    $\begingroup$ @blunders, If you define "organism" as something able to reproduce, then the question is clearly nonsense. I'm fairly certain that there is no conceivable mechanism by which the earth meaningfully "reproduce" in the way that living organism do. $\endgroup$
    – naught101
    May 1, 2014 at 7:22
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Answer is no, Earth not an organism. Key reason being that life without reproduction is not life, and there is no logical proof that Earth reproduces using a type of reproduction never observed, or is proof that life does not require reproduction.

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    $\begingroup$ is an infertile human a life form? $\endgroup$
    – Kenshin
    May 21, 2014 at 3:19
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    $\begingroup$ Bit vague, but I'll attempt to respond. In my opinion, an infertile "species" is not a life form, which is to say, without reproduction being present within a species, the species would not exist. Ants would be a great example of where some members of the species by "design" do not directly reproduce, though the species does. $\endgroup$
    – blunders
    May 21, 2014 at 3:26
  • $\begingroup$ +1 Succinct and to the point. $\endgroup$
    – Jack Aidley
    Nov 20, 2014 at 17:13
  • $\begingroup$ perhaps the answer proper would gain more attention if it included the "species" comment $\endgroup$
    – nilon
    May 31, 2017 at 16:36
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Interesting question. I think many issues of self-regulation and so forth have been addressed but what is really up for debate is whether the Earth can reproduce.

I answer with yes it is possible the Earth is an organism because it is possible for it to reproduce. Through intelligent life that is able to develop technology, this life is able to reproduce the Earth (assuming living creatures are part of the Earth - like cells of the Earth). We can think of the inanimate features of the Earth (e.g. atmosphere) like the blood of the organism that must supply the right Milieu intérieur for it's cells, the living creatures of the Earth. The humans are analogous to the planets sex cells, because through humans, the most intelligent of Earth's species, the Earth is able to replicate itself through technology in the ways listed below:

There are two potential ways that humans can be used to replicate the Earth. The first way, is that because humans have adapted to fit in with the inanimate features of the Earth, if humans are to inhabit another existing planet, they must transform this planet into another Earth with the same properties of the Earth, that are compatible with human life, in order for that planet to be suitable for them. Humans have evolved to be suited the Earth's conditions, and therefore any planet they wish to inhabit must have these same features of Earth. It is a neat method of reproduction - evolve a species to need you, so it will later be forced to reproduce you. This effectively replicates the Earth. The second way humans could replicate the Earth is directly producing another planet that has the same features of Earth using technology.

While at present we have no record of living creatures having replicated a planet it is certainly plausible, and therefore it is plausible that the Earth is a living organism, given that it is possible for it to reproduce and self regulate through negative feedback mechanisms observable in nature.

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    $\begingroup$ Re: "It is a neat method of reproduction..." Yep. Humans are as much a part of Earth as our brain cells are part of us. $\endgroup$
    – user2338816
    Apr 27, 2014 at 2:52
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    $\begingroup$ This kind of works if you apply it to the biosphere, but not the earth as a whole. And we're heading way out into science fiction here, and quickly leaving science behind.. $\endgroup$
    – naught101
    May 1, 2014 at 7:25
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    $\begingroup$ When ants move from a tree onto a new tree, this does not make the tree reproduce. $\endgroup$
    – Nicolas Barbulesco
    May 3, 2014 at 18:47
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    $\begingroup$ @NicolasBarbulesco, that is because ants are not byproducts of the tree, but humans and ants are byproduct of the Earth. So if the Earth generates humans, and humans generate a new Earth, then Earth has reproduced. And just as animals can use existing proteins and molecules to reproduce themselves, planets can use existing floating lumps of rock to reproduce themselves, via humans, the cells of the Earth. $\endgroup$
    – Kenshin
    Sep 30, 2014 at 5:33
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Whether it's an organism, it's alive, etc. are just labels commonly used when this issue is discussed among biologists or Earth scientists. However, a broader perspective leads to the notion of an emergent system.

"Emergence occurs when an entity is observed to have properties its parts do not have on their own, properties or behaviors which emerge only when the parts interact in a wider whole" (https://en.wikipedia.org/wiki/Emergence).

The properties that we often associate with life are not specific to life, but to complex systems with emergent properties. Therefore, exhibiting specific properties commonly associated with life doesn't imply the Earth is alive (although it does not deny it). Whether it fits into the definition of an organism, it's again just a matter of definition. There's, however, no doubt that the Earth is yet another example of a complex system giving rise to emergent properties, which is why it allows us to refer to it as an organism or as an alive entity sometimes.

See also: https://en.wikipedia.org/wiki/Self-organization and https://en.wikipedia.org/wiki/Complexity. Again these concepts are commonly associated with alive organisms but are not exclusive to them. I think the problem here might be that, although these properties are not only of alive organisms, they are many times among the characteristics that we use to define what life is. Again, this is mostly a matter of definition.

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No

The Earth is not a living thing and therefore not an organism. Life is defined by several things:

  • Growth
  • Reproduction
  • DNA/RNA
  • Oxygen Exchange (Except for some organisms)

It is valid to say that earth is giant habitat for life. Earth can be described as a huge magnet and a hot rock orbiting a giant sun that will one day wipe out life on Earth. All human life is projected to be extinct between 5,100 and 7.8 million years from now Source

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  • $\begingroup$ But the earth will survive many millions of years from now. Get it? $\endgroup$
    – Tardy
    Feb 25, 2021 at 13:56
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    $\begingroup$ Your "source" doesn't say that "all life" will be extinct; it's only for humans (with a 95% confidence), and this doomsday argument has long been debated. $\endgroup$
    – Jean-Marie Prival
    Feb 25, 2021 at 14:25
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    $\begingroup$ I don't see why something needs DNA or reproduction to be an organism. Organism also refers to "a system consisting of parts that depend on each other" (oxfordlearnersdictionaries.com/definition/english/organism). In this sense, the Earth meets the criteria to be considered an organism (which is not to say that it's alive) $\endgroup$
    – rasmodius
    Feb 25, 2021 at 16:20
  • $\begingroup$ @kastellane you're wrong check out this google.com/… a cell has DNA and RNA $\endgroup$
    – Tardy
    Feb 25, 2021 at 19:02
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    $\begingroup$ DNA is a way to store a genetic code using nucleic acids. If there was a species using other chemicals than the usual nucleic acids to achieve the same mechanisms of replication, (exotic) proteins manufacturing, etc, no serious biologist would deny it being a lifeform on the sole account this is not DNA. This is ridiculous. $\endgroup$
    – Winston
    Feb 27, 2021 at 20:34

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