Gaia – Yes or No ? (12-18 yr old)


Gaia image by Josephine Wall (the presence of Gaia)

My question is, do you believe the arguments outlined below, or not? Read the arguments and make your own post on your own blog or comment on this blog on your decision. 

Enjoy the arguments, make your own decision.

In Greek mythology, Gaia is the ancestral mother of all life: the primal Mother Earth goddess.

The Gaia hypothesis (proposed by James Lovelock) argues that the organic and inorganic components of Planet Earth have ​evolved together as a single living, self-regulating system.

It suggests that this living system automatically controls global temperature, atmospheric content, ocean salinity, and ​other factors, that maintains its own existence and life on our planet. In a phrase, “Life maintains conditions ​suitable for its own survival.” In this respect, the living system of Earth can be thought to be similar to the workings of an individual organism that regulates body temperature, ​blood salinity, etc. So, for instance, even though the luminosity of the Sun – the Earth’s heat ​source – has increased by about 30 percent since life began almost four billion years ago, and lots of other elements continue to change, ​the living system has reacted as a whole to maintain temperatures, and other life determining properties, at levels suitable for life.

(slightly adapted from​)

Look at the Stories before making your decision.


The Stories

Story One – The atmosphere

The atmosphere of the Earth has over the last million years maintained an oxygen level of 20.3-21%. The lower percentage was determined by analysing  ice cores extracted in the Antarctic and Greenland which was formed over 800,000 years ago.

Oxygen is chemically recognised as a very reactive gas, it will react with Nitrogen and Methane over time. Increase the percentage to 25% and lighting a match would start a fire that you would have difficulty extinguishing. Reduce the level to 12% and life as we know it would very difficult (12% is the Oxygen level on our tallest mountains). How has the planet maintained these levels?

Carbon Dioxide levels are rising. There is evidence that this started soon after the industrial revolution in Britain in the 18th Century and has continued to do so in subsequent centuries. There is possible evidence that this rise will caused a ‘greening’ of the environment as Carbon Dioxide becomes  more available for the Earth’s plant life.

Carbon Dioxide is a ‘greenhouse gas’ which prevents the Sun’s heat leaving the planet. However clouds also share that role.There is aso evidence that the oceans provide a ‘sink’ for carbon dioxide where they form carbonates.

An interesting story. Go back millions of years and we have the first living things beginning to populate the land. Fossil evidence indicated these were mosses. They had no challengers, there were no animals, no other plants. They spread, and they spread. Plants breathe in Carbon Dioxide and exhale Oxygen ….there were so many of them that the Carbon Dioxide levels in the atmosphere were destroyed … no greenhouse effect, the Earth’s heat escaped. The result was the Earth’s first ice age. Almost all the  mosses died. Others then moved on to occupy the land, some breathed in Oxygen and exhaled Carbon Dioxide. Life continued.

Trees like the moss in the above story are a major sink for CO2, plant life ‘breathes in’ CO2, uses it to grow and exhales O2. Deforestation would therefore have a negative impact on the environment. Eventually when trees die the carbon they are made of becomes CO2. Growing a lawn does not necessarily have a negative CO2 effect …any idea why?

So are the above phenomena just feedback loops or are they a deliberate intervention by a living planet?


Story Two – The temperature

The average temperature of the Earth has been maintained between 10 and 200C for billions of years while the Sun’s output has increased 10-20% over the same period. With 2016 coming to its end it has been noted by NASA that this has been the hottest year on modern records.


In the above graph the average  ie the 0.0 line is 14.6 0 C

However there have been in the last 650,000 years seven cycles of glacial advance and retreat, with the abrupt end of the last ice age about 7,000 years ago marking the beginning of the modern climate era — and of human civilization. Life has survived all of these external disturbances. Look at this latest NASA video

Where can the heat hide? The main reservoir for any excess heat are the Earth’s oceans. The oceans are also a major source of cloud formation. 

Clouds are sometimes underestimated in terms of thinking about global warming, however clouds are  a tremendously important part of our environment.They can support the greenhouse effect – probably more so than CO2. But they can also counteract global warming by the way in which they move water around and act as reflective shields of the Sun’s energy.

Recent hurricane activity in the Pacific (September 2016) was caused by water movement. Incredible amounts of water, from the warm oceans of the equator, evaporated into the atmosphere, forming clouds, this process lead to the cooling of the ocean and a greatly disturbed atmosphere which then distributes its energy over the nearby environment in the form of hurricane Gaston.

Clouds can also be formed by other means, organic vapours released by organisms such as trees, and livestock appear to play a far more important role in cloud formation than has been suspected.

But it could be argued that hurricanes and associated weather conditions are a way in which the environment (Gaia) is trying to negate the effects of global warming or again are they feedback loops?

Story Three – Salinity

Somehow the salinity (salt content) of Earth’s oceans has been maintained over the last 300 million years. How do we know this? The building blocks of living things, the cells that they and we are made of, cannot survive beyond levels of 6% salt content. However life has survived. There is also evidence from ice samples ( the ones in Antarctica go back to ice created almost 1 million years ago) that salinity levels have remained the same.

We know that the salinity of the blood of whales, mice, humans and most fish, whether dwelling in the sea, on land or in fresh water are the same. So how have the oceans maintained a constant salinity level while millions of tonnes of salts are dumped in them all year round, via rivers, earthquakes, and other natural events?

There is sometimes a complacency in our views on the nature of our oceans. They support the growth of a greater biomass (animals and plant life) than that of the land based environments. There are therefore some thoughts that the biomass contributes in some way to maintaining salinity levels by incorporating salt in their skeletal structures which then become part of the sediment of our oceans.

There are also ideas on ocean ‘cracks’ recirculating sea water and removing excess salt. Another model is CO2  absorption in sea water which reacts with excess salt and deposits insoluble carbonates.

Story Four – Plankton

There are suggestions that increased heat, leads to increased plankton growth then greater production of a compound called Dimethyl Sulphide as the plankton decompose leading to greater sulphur dioxide concentrations in the atmosphere which leads to greater cloud formation  and then leading to greater sunlight reflection. Thus a cooling effect on the oceans.

The final analysis.

Life was first thought to have emerged on planet Earth about 4 billion years ago. Since that time life in it’s variety of forms has continued to survive and evolve, despite dramatic changes in the environment of our planet. At times some forms of life have been extinguished  (dinosaurs are one of many examples) but other forms of life have survived and new ones have developed.  The argument for Gaia is that it is the ‘living’ planet that has provided the conditions for this survival. An alternative argument is that by some lucky event the planet has an environment that can adapt itself to changing circumstances via a variety of feedback loops.


This is the crux post. What do you think?

Do you think that a living, life supporting, Gaia is a realistic possibility?

Do you think that the predicted outcomes are realistic based on the evidence and ideas that you have been presented with? Or do you think that what happens to the the elements mentioned in the stories is just the result of a feedback loop?

What aspects of what you have been presented with would you challenge?

Why do you think that I have presented this as an hypothesis and not a theory?

Thank you for reading. I hope that it has provoked some thinking. It provoked my thinking. I welcome comments.


For those who are making comments. If you give your blogs URL I will reply on your blog. If I don’t have that URL I will reply on this site.


31 thoughts on “Gaia – Yes or No ? (12-18 yr old)

  1. I very much doubt that the earth is its own living organism. We have no signs of the earth being animate, but it could be living deeper, and we have just not drilled deep enough to find it. Just like the micro organisms on our skin, we are very small in comparison to the earth, and it could just be that it is so big and hidden we are unnoticed. I think that the earth is inanimate however, because there has been no sign of action that would hint towards life. We also have not seen anything that would be required for an organism to live. No sensors have picked up anything from deep within the earth to hint at anything, this is why I think the earth is inanimate.

  2. Alex
    Thanks for those thoughts. I first visited Lovelock’s hypothesis at least 20 years ago and was impressed by his arguments. Since then I have slowly moved to a feedback scenario and I get the impression from his books on the subject that he has changed his thoughts. I don’t however believe that your idea of ‘drilling’ deep’ is an approach to disproving the hypothesis. I think the falsification will be linked more to surface research. It is interesting that science is claimed to develop by scientists ‘falsifying’ other scientist’s work … this could be it in action.

    Thank you very much for your comments.


  3. No the earth isn’t its own organism because the earth doesn’t actually have any organs and for many years we have been making industrial performances on earth and underground long enough for the earth to die if it was an organism. Also, the earth doesn’t actually breath through anything. Under the crust of earth is molten rock and hot boiling lava and no living organism can survive when their insides are constantly burning and are at sky high temperatures.The earth cannot be a living thing because it doesn’t have traits of life besides what grows on top.

  4. This “Gaia hypothesis” hypothetically depicts Earth’s naturally occurring events. I believe that Earth has the possibility of being a complex organism that naturally changes its functions as a means to adapt to its own internal state, and us humans, simply being part of a larger system. This “Gaia hypothesis” is merely a hypothesis, not a theory because unlike a theory it’s not used much as the subject of a completely coherent statement explaining observed facts. In the end, I’d like to argue that Earth is simply a large self-regulating potato shaped planet orbiting the nearest star in its own galaxy.

  5. Maxim,
    Many thanks for your comment. First let us consider what I mean by an organism. From a biological perspective the definition is ‘a system with many parts that depend on each other and work together’. In this sense I could argue that the atmosphere, the sea, the temperature,the plants, the animals are all parts of the entity which is called Gaia. I suppose Gaia would be a ‘surface’ entity because as you have said ‘its what grows on top’. I like the idea of this ethereal entity looking after the living environment and reacting to changes to it. I do however think that a lot of what we are seeing within our present environment and in the past is part of a series of feedback loops.

  6. loicisd20
    I tried to access your blog, but failed so my answer is in this comments area. Many thanks for your reply. In my view the crux of your statement is that “us as humans are simply part of a much larger system”. When you think of the millions of different living things that live and survive on our planet it is quite humbling. In a sense they all have their own Gaia.
    As I have mentioned in other comments I am slightly moving from a Gaia model to a feedback model. It is a battle that is helped by your sensible and thoughtful feedback. I am also pleased by your focus on the hypothesis focus of your arguments.

  7. this is a really cool idea. i think that it is correct. we can even see this by watching just a small part of an ecosystem. for example if there are too many dear then the wolves will find it easier to kill one and will bring back down the population until there are to many wolves for the amount of dear. then wolves would die and then more dear could live. in the end it would balence out.
    except for one thing. humans would interfier and kill the dear for food. i believe that humans are not part of the global organisme but we are like a virus praying upon it.

  8. Hello, I personally believe in the Greek Gods. This Gaia concept appears to me to be true because I already think Gaia exists, I feel really good about knowing that there are proofs showing that Earth could be a connected environment, like an organism.

  9. 20issav

    Thank you for your comment. I am replying here because you did not supply your blog URL.

    A lot of people support the hypothesis put forward by james Lovelock. Note that it is a hypothesis and not a theory. A hypothesis is an idea about something which needs to be proven by experimentation or measured observation.

    I like your wolves analogy. Lovelock produced a game called ‘Daisy World’ which is based upon a similiar model.

    Lovelock’s Gaia suggests that we (humans) are really no different from the other hundreds of thousand species on the Earth. Maybe we are a virus? If so we would be like other viruses and be a threat. Gaia will then act accordingly.

    Remember it is a hypothesis.


  10. titouanisd20

    Thank you for your comment.
    I would reply to it on your own blog if you had supplied the URL.

    Lovelock suggested that Gaia could be looked at as an organism. (An organism is a living entity composed of many interrelated components that work together to achieve a common goal.)
    This was an hypothesis – a hypothesis is an idea that has yet to be proven. If proven it becomes a theory.

    I accept that there might be a lot of proof for the individual aspects of the Gaia hypothesis BUT I believe that the interconnection between these elements needs further examination before Gaia can be accepted as a theoretical possibility.

    I like your argument, clear and concise. Many thanks.


  11. Dear Eugene,

    I think that you have presented this post as a hypothesis instead or a theory because a hypothesis is proposed explanation made of limited evidence as a starting point for further investigation. A theory is a system of ideas intended to explain something. This post was a proposed explanation with some/limited evidence to start another investigation. This is the link to my blog:


    Replied on blog

  12. Many people have been debating over the years about the Gaia hypothesis. The hypothesis argues that the organic and inorganic components of Planet Earth have ​evolved together as a single living, self-regulating system. I am unsure if I support this argument. I agree that the Earth has a system using abiotic and biotic factors keep things steady over time but I disagree that it is a living organism. The longest living organism has lived for about 5,000 years, and yet it is a microscopic bacteria. I find it impossible for the Earth to live over 4 billion years, especially from what we have done to ruin the Earth.

  13. Bryan,

    Many thanks for your thoughtful comment. Yes you are right. I read Lovelock’s first book “A new look at life on Earth’ over 20 years ago (it was published in 1979). I have therefore been thinking (on and off) about it for some time. I must admit to being a great believer 20 years ago (my students loved it), however over the years doubt has crept in. I am however still bemused by the way that the crucial factors that are essential for life on our planet for bacteria, ants, humans, dinosaurs, fish and all other living things have been maintained over such a long period. Are there some complicated feedback controls operating somewhere which nobody has noticed or maybe it’s just life itself. For example you get an excess of carbon dioxide, plants love it, grow bigger, remove more carbon dioxide from the atmosphere. Oceans absorb it as well and plankton growth blooms.
    The feedback for humans (only 70,000 yrs around) will be incredible weather conditions, droughts, flooding (of whole land areas), tornadoes, hurricanes and maybe worse. Result population decreases Earth ruination is halted.

    Just thoughts. Again many thanks for yours, very stimulating.

    If you had included you blog address in your comment I would have posted this on your blog.

    Mike (Farmer)

  14. Hi Mr. Farmer! My name is Kiana and I am from California. I really liked how you supported your hypothesis with supporting evidence. The evidence that you presented me with made me believe that Gaia is real because many other planets can’t support life on them because their either too hot or too cold. Anyways, here is my link to my blog:

    And this is my link to my blog post about your hypothesis about Gaia:

    Replied on blog

  15. Dear Mike,

    I personally believe the Gaia hypothesis. I’ve believed myths from many different ancient cultures starting from when I was about eight years old, and those beliefs have stuck in my mind. I’ve heard stories about Gaia in Greek mythology, and the Gaia hypothesis sounds very much like the myths.


    Replied on blog

  16. Dear Mr. Farmer,
    When I was reading your post I was intrigued at some of the new information that I had discovered about the earth and how it maintained the atmosphere, oxygen, and temperature levels. On the other hand when I was reading I kept thinking of the fact that Gaia, the goddess of the earth, was from Greek and Roman mythology witch is one of things to read about. I also enjoyed reading your post very much.
    – Alex O

  17. I think that earth is not a living being but a carrier of life like how a rock has ants on it or how a tree has fruit.

  18. Dear Mike Farmer,
    I like how you put this blog post into a science post with the hypothesis and theories and things. Thank you for teaching me about the Gaia Hypothesis.
    Come and check out my blog at:

  19. Hi Mark,
    I think the Gaia theory is in a way correct. I think that we should take care of Earth. I just don’t think that Earth can be a living human being.


  20. Tyler
    I liked your comment.
    I agree with your initial statement. I think the Gaia hypothesis (note the word hypothesis – instead of theory) is in a way correct.
    According to early thoughts on Gaia, we should take care of the Earth otherwise the Earth might take care of us (ie make human life undearable). The melting ice cap in the Artic – where temperatures are 20 degrees C higher than any other recorded temperature could influence weather patterns that could make areas of the Indian ocean uninhabitable.

    I again agree the Earth cannot be considered as a living human being BUT not all living things are human beings.

    Thanks for your stimulating comment.

    Mike (not Mark) Farmer

  21. Aaron
    Many thanks for your post. Did you post your post on Gaia on your website? If so I am unfortunately not allowed to access it via the above address.

    I agree my answers are repetitive, that maybe due to the nature of the questions that other responders have asked. It also reflects my thoughts with respect to the Gaia Hypothesis.

    Thanks for the post Aaron.

  22. Dear Mike Farmer
    Thank you for posting this very interesting post. I have learnt a lot about Greek mythology and has encouraged me to learn more about this subject.

    Thanks for the post mike.

  23. I liked this idea and also believe in Greek gods myself. I personally would like to learn more about Greek mythology.

Leave a Reply

Your email address will not be published. Required fields are marked *