The Gaia Hypothesis: why some scientists believe that the Earth is a huge organism, and whether it is true

What is this hypothesis and who came up with it

Gaia is the ancient Greek goddess of the Earth, and she is mentioned in the name for a reason. According to the hypothesis, our planet is a huge self-regulating organism, and animals, plants and inanimate nature are its parts. The Earth, as if a good goddess, maintains a suitable climate and helps life develop.

Some supporters of the hypothesis even believe that Gaia is capable of “recovering” from all kinds of disasters. For example, to survive a meteorite fall, a very powerful volcanic eruption and active human influence.

At first glance, the theory seems a little strange. However, it was developed by respected scientists: British chemist James Lovelock, a member of the Royal Society of London, and Professor Lynn Margulies, an American biologist.

It all started back in the 1960s, when Lovelock was advising NASA on life on Mars. The scientist found a simple way to find out the answer: to analyze the atmosphere of the red planet. It turned out that neither Mars nor Venus had much oxygen and methane – gases produced by living organisms.

It was then that Lovelock noticed the unique composition of Earth’s atmosphere. This led the researcher to the idea that life itself consumes and releases gases so that the planet retains the conditions for its existence.

The more oxygen-breathing creatures appear on Earth, the more carbon dioxide becomes in the atmosphere. But the Earth doesn’t turn into a lifeless planet like Mars. Carbon dioxide is absorbed by plants, which only multiply better with more carbon dioxide in the atmosphere. This means they produce more oxygen. As a result, the balance is not disturbed.

Lovelock began to develop the idea and eventually came to the conclusion that the Earth is a unified and well-oiled system, the same Gaia. Thanks to the complex interconnections between living and non-living nature, the planet has maintained optimal conditions for its inhabitants for 3.8 billion years.

Although many scientists did not support Lovelock’s theory, the Gaia hypothesis became famous and quite popular. The British chemist even received awards from the Geological Society of London, NASA and several other organizations.

Why some scientists supported the Gaia hypothesis

The idea that the Earth was a huge organism proved appealing. The hypothesis both explained everything and was quite simple and beautiful at the same time. Not surprisingly, the theory had many admirers. Including among the adherents of New Age. The latter began to speak of an intelligent Earth and of science confirming the ancients’ tales of Mother Nature.

Lovelock himself was repulsed by such interpretations and even repented of his choice of the name of the hypothesis. But this didn’t help him to avoid the dissatisfaction of scientists, who considered that a new sect was being created under the guise of science.

Nevertheless, the hypothesis had supporters in academic circles. Largely because some of the theory’s assumptions have been confirmed in practice.

The seas maintain a salt balance

Minerals from land and rivers constantly enter the world’s oceans. If it were not for the interaction of animate and inanimate nature, all the seas would have long ago turned into lifeless salt reservoirs like the Dead Sea. But this is not the case: the concentration of salt in seawater has not changed for millions of years.

Lovelock suggested that salt is deposited on the seafloor, and that the same corals have a positive effect on the salinity of the ocean. It is now really believed that the seas are capable of self-regulating in similar ways.

The Earth has “adapted” to changes in the brightness of the Sun
Since the first organisms appeared on our planet, the brightness of the star has increased by 25-30%. Despite the new conditions, the Earth has maintained a suitable temperature for life.

According to Lovelock and his colleagues, this was due to microorganisms. When the temperature rose, plankton began to multiply more actively, and the products of their vital activity increased as a result. This included dimethyl sulfide gas. When it was released from the water into the clouds, the clouds began to reflect sunlight better, and the temperature on Earth dropped.

Later, dimethyl sulfide was found in the clouds.

Computer models of the self-regulating environment work

In the 1980s, Lovelock created the Daisyworld model. It was a simplified demonstration of Gaia’s ability to self-regulate.

“Daisyworld” was populated by only two kinds of plants: black plants, which absorb light, and white plants, which reflect it. The former, respectively, preferred coolness, while the latter preferred warmth. The model turned out to be very stable. So, if the number of blacks increased, the surface of the planet reflected less light, and it became warmer. And that led to a proliferation of white plants.

Can the Earth really be considered a huge organism?

Lovelock’s theory lacks precision. For example, not even all of its supporters are sure whether the Earth can be called a single “living” organism. For example, Lynn Margulis insists that the hypothesis only shows how living and non-living things evolve together through close interconnection.

There are also concrete examples that prove that “mother nature” is not always in control of her children. They often themselves upset the balance of the system.

The Earth is not able to fully regulate its atmosphere and temperature. For example, trees simply don’t have time to absorb excessive carbon dioxide: its amount in the atmosphere grows 17 times faster.

And the organisms that inhabited the Earth often had a detrimental effect on the planet’s climate. For example, about 2.4 billion years ago, when oxygen-producing bacteria appeared through photosynthesis, the amount of methane in the atmosphere dropped dramatically. This led not only to the glaciation of the Earth, but also to the death of many microorganisms. Contrary to Lovelock’s theory, they were unable to rebuild their populations.

The Earth is much more complex than the “world of daisies. There are a huge number of species living on our planet, and their evolution cannot be unidirectional.

How useful is the Gaia hypothesis

Still, Lovelock’s idea isn’t just a beautiful metaphor. It has stimulated the study of our planet as one big ecosystem, not a collection of parts. Today no one doubts that living and non-living nature are interconnected and can influence each other. This idea lies at the heart of modern ecological science.

Paradoxically, Lovelock’s theory of the Earth’s self-regulation, on the contrary, has shown how fragile the balance of nature is. At a time when our planet’s climate is changing dramatically, such a reminder is especially important. And in this sense, the Gaia hypothesis has played its positive role in science.