Planetary intelligence: Can an entire planet think like we do?

This is the "thought experiment" of a group of scientists who blended empirical knowledge of the Earth with more generic ideas about how life changes worlds. And, in the International Journal of Astrobiology, they explored the possibility of a "planetary intelligence", which they say in a new research paper, might happen as an epiphenomenal consequence of cognition acting on a planetary scale.

It's a big, sweeping theory, but it could lend explanatory power to researchers looking for ways to mitigate the acceleration of global climate change.

The Earth as a self-sustaining organism

"If we ever hope to survive as a species, we must use our intelligence for the greater good of the planet," said Adam Frank, the University of Rochester's Helen F. and Fred H. Gowen Professor of Physics and Astronomy, in a press release.

Working with Sara Walker of Arizona State University and David Grinspoon of the Planetary Science Institute, the team pooled a body of ideas, like the Gaia hypothesis.

The Gaia hypothesis predicates a strong relation between the Earth's biosphere, and the collection of non-living geological systems of water, land, and air — all working to maintain the Earth's homeostasis, and human-friendly levels of habitability. The pitch for the theory is that the totality of life generates a planetwide system that keeps to a status quo.

It turns out that the roots of trees that span a complex network under forests are connected to fungi networks, called mycorrhizal networks, said Frank, in the release. When one section of the forest is short on nutrients, other regions send it everything it needs to survive through the mycorrhizal network. This lateral capability enables a forest to maintain its homogeneity.

The researchers say human civilization is an "immature technosphere," consisting of a collection of human-made systems and technology that directly and adversely affects the planet — but lacks the ability to maintain its initial relationship to the planet. For example, most of the energy we use relies on fossil fuels that fundamentally alter the planet's atmosphere and oceans.

Human technology reigns

Make no mistake: this technology will threaten humanity's chances at survival. And to change the planet's atmosphere into a non-habitable state, humans will have to work together.

There are many ways we could do this, and have been able to for centuries. But Frank and his colleagues suggest a four-stage heuristic for their "thought experiment," and propose that these might be stages in the evolution of a planetary intelligence more broadly.

Stage 1 is the "immature biosphere," which the researchers say happened when the Earth was very young, billions of years ago. This was before a technological species had matured, when microbes existed, but not plants. Global feedback loops couldn't happen yet, since there was no mature biosphere.

The second stage is the "mature biosphere," which was the Earth from roughly 2.5 billion to 540 million years ago. The continents stabilized, along with the emergence of plants and photosynthesis. Oxygen became abundant, and with it, the ozone layer. This created the biosphere, which may have contributed to levels of habitability necessary for us to evolve.

Third, of course, is us — in the "immature technosphere" of today, where interlinked systems of technology, computers, electricity, communication, and transportation reign. But none of them are integrated with the other systems of the planet, like the biosphere, atmosphere, or oceans.

"Instead, it draws energy from Earth's systems in ways that will drive the whole into a new state that likely doesn't include the technosphere itself," say researchers in a statement released with their findings.

In this phase of the researchers' module-friendly system, the technosphere is going to destroy itself.

Toward a "mature technosphere"

And the answer to this plight, according to the researchers, is stage 4: a "mature technosphere." In this hypothetical stage, the technosphere is fully integrated with the Earth's systems, and actively works to maintain its habitability and long-term survival — like the network of fungi helping a starving region of a forest. "Planets evolve through immature and mature stages, and planetary intelligence is indicative of when you get a mature planet," says Frank.

"The million-dollar question is figuring out what planetary intelligence looks like and means for us in practice because we don't know how to move to a mature technosphere yet," adds Frank.

Right now, nearly every industry around the globe — from energy production to the automotive industry — is working to slow its pull on the Earth's resources. Much of the technology we've created to help us do that, like lithium-ion batteries and carbon capture, leave much to be desired.

Sustainable encouragement - And a heuristic of social progress like Frank and his colleagues' could be one way of creating a better understanding of where we're going.

But it's important to remember that just because we can imagine a goal, doesn't mean it's the correct one, or even one that exists at all. Sometimes the light at the end of the tunnel is, indeed, another oncoming train.

Suffice to say that while the human "technosphere" needs to adapt to a more balanced relationship with the Earth's systems, in the end it won't be the ways we imagined we'd get there, but the journey itself, that gets the job done.