New Delhi: Earth is the only known habitable planet in the entire universe. The collective activity of life, including all microbes, plants, and animals, has impacted the planet. 


For instance, plants undergo photosynthesis to enhance their own survival. The release of oxygen during photosynthesis has changed the entire function of Earth. 


Thus, the collective activity of life, known as the biosphere, helps change the world. Now, a question arises that could the collective activity of cognition, and action based on this cognition, also change a planet? 


Our planet took on a life on its own, once the biosphere evolved. In a new study, researchers have posed the following question: If a planet with a life has a life of its own, can it also have a mind of its own?


The study, conducted by Adam Frank, professor of astrophysics at the University of Rochester in New York, and his colleagues David Grinspoon at the Planetary Science Institute in Arizona, and Sara Walker at Arizona State University, was recently published in the International Journal of Astrobiology. 


What Is The “Thought Experiment” About?


The researchers' self-described "thought experiment" combines current scientific understanding about the Earth with broader questions about how life alters a planet, according to the study. 


In the study, the researchers have discussed what they call "planetary intelligence" to raise new ideas about the ways in which humans might tackle global issues such as climate change. Planetary intelligence is the idea of cognitive activity operating on a planetary scale.


In a statement issued by University of Rochester, Frank said "if we ever hope to survive as a species, we must use our intelligence for the greater good of the planet."


Earth's Civilisation An 'Immature Technosphere'


In order to explain that even a non-technologically capable species can display planetary intelligence, Frank, Grinspoon and Walker have drawn from ideas such as the Gaia hypothesis, according to the study.


The hypothesis proposes that the biosphere interacts strongly with the non-living geological systems of air, water, and land to maintain Earth's habitable state. The collective activity of life creates a system that is self-maintaining, because of which even a non-technologically capable species can display planetary intelligence.


According to Frank, many recent studies have shown how the roots of the trees in a forest connect through underground networks known as mycorrhizal networks. The forest is able to maintain its own viability through an interesting mechanism. If one part of the forest requires nutrients, the other parts send the stressed portions the nutrients they need to survive, via the mycorrhizal network, the study said.


The researchers have called our civilisation an "immature technosphere" in the study. An immature technosphere is a conglomeration of human-generated systems and technology that directly affects the planet but is not self-maintaining, according to the statement.


The majority of our energy usage involves consumption of fossil fuels that degrade Earth's oceans and atmosphere. Our home planet is being destroyed by the technology and energy we consume to survive. This, in turn, will destroy our species, according to the study. 


For instance, certain technological capacities such as nuclear weapons may lead the world's species, or at least its global civilisation, into a kind of suicide, the study said.


In order to survive as a species, humans need to collectively work in the best interest of the planet. Frank said there is intelligence on Earth, but there isn't planetary intelligence, according to the statement. 


How Can Earth Evolve Into A "Mature Technosphere"?


The researchers, in the study, have highlighted four stages of Earth's past and possible future to illustrate how planetary intelligence might play a role in humanity's long-term future. The researchers have shown how these stages of evolution driven by planetary intelligence may be a feature of any planet in the galaxy that evolves life and a sustainable technological civilisation, according to the study.


The Four Stages Of Earth's Past And Possible Future


The four stages of Earth's past and possible future are 'Immature Biosphere', 'Mature Biosphere', 'Immature Technosphere', and 'Mature Technosphere'. 


Immature Biosphere


This is the first stage, and is characteristic of very early Earth, billions of years ago, and before a technological species. During this period, microbes were present but vegetation was yet to come. 


Since life could not exert forces on Earth's atmosphere, hydrosphere, and other planetary systems, there was some global feedback.


Mature Biosphere


This is Stage 2, and is characteristic of Earth, also before a technological species, from about 2.5 billion to 540 million years ago, according to the study. 


During this stage, stable continents formed, vegetation and photosynthesis developed, oxygen built up in the atmosphere, and the ozone layer emerged. Also, the biosphere exerted a strong influence on Earth. The influence could have been exerted to help maintain Earth's habitability, the study said.


Immature Technosphere


This is the third stage, and is characteristic of Earth now, with interlinked systems of communications, transportation, technology, electricity, and computers, according to the study. However, the technosphere is still immature because it is not integrated into other Earth systems, such as the atmosphere. 


Instead, the technosphere draws matter and energy from Earth's systems in ways that will drive the whole into a new state that likely does not include the technosphere itself, according to the study. 


In the long run, our current technosphere is working against itself, the statement said.


Mature Technosphere


This is the fourth stage. According to Frank, this is the stage where Earth should be in the future, with technological systems in place that benefit the entire planet, including globally harvesting energy in forms like solar energy that do not harm the biosphere. 


According to the study, the mature technosphere is the one that has co-evolved with the biosphere into a form that allows both the technosphere and the biosphere to thrive.


Quoting Frank, the statement said that planets evolve through immature and mature stages, and planetary intelligence is indicative of when one gets to a mature planet. He further said that the million-dollar question is figuring out what planetary Intelligence looks like and means for the Earth in practice because "we don't know how to move to a mature technosphere yet."


Complex System Of Planetary Intelligence


Humans do not yet know specifically how planetary intelligence might manifest itself. The researchers noted in the study that a mature technosphere involves integrating technological systems with Earth through a network of feedback loops that make up a complex system. 


Anything which is built from smaller parts that interact in such a fashion that the overall behaviour of the system is entirely dependent on the interaction is a complex system, according to the study. 


In a complex system, the sum is more than the whole of its parts. Forests, the Internet, financial markets, and the human brain are some examples of complex systems, according to the study.


A complex system, by its very nature, has entirely new properties that emerge when individual pieces are interacting. For instance, it is difficult to discern the personality of a human being, solely by examining the neurons in his or her brain, the statement said.


This implies that it is difficult to predict exactly what properties might emerge when individuals form a planetary intelligence, according to the study. 


According to the researchers, a complex system like a planetary system will have two defining characteristics. Planetary Intelligence will have emergent behaviour, and will need to be self-maintaining, according to the study.


Quoting Frank, the statement said that the biosphere figured out how to host life by itself billions of years ago by creating systems for moving around nitrogen and transporting carbon. He said that now "we have to figure out how to have the same kind of self-maintaining characteristics with the technosphere."


Search For Life & Civilisations Outside Solar System


Frank said that Earth does not have planetary intelligence or a mature technosphere yet, despite some efforts, according to the statement. These efforts include global bans on certain chemicals that harm the environment and a move toward using more solar energy. 


Frank further said that the whole purpose of this research is to point out "where we should be headed."


He said that raising these questions will not only provide information about the past, present, and future survival of life on Earth, but will also help in the search for life and civilisations outside our solar system. 


For instance, Frank is the principal investigator on a NASA grant to search for technosignatures of civilisations on planets orbiting distant stars. 


According to the statement, Frank said that the only technological civilisations we may ever see are the ones that did not kill themselves. He said that this means they must have reached the stage of a true planetary intelligence. 


Frank further said the power of this line of inquiry is that it unites what we need to know to survive the climate crisis with what might happen on any planet where life and intelligence evolve.