Tie-dye, geopolitical tension and a digitized Abba back on stage. Our appetite for revisiting the 1970s shows no signs of waning. Science writer Ferris Jabr has now reanimated another idea that captured the era’s zeitgeist: the concept of a “living Earth”. In Becoming Earth: How Our Planet Came to Life Jabr makes the case that our planet is far more than a lump of rock that passively hosts complex life. Instead, he argues that the Earth and life have co-evolved over geological time and that appreciating these synchronies can help us to steer away from environmental breakdown.
“We, and all living things, are more than inhabitants of Earth – we are Earth, an outgrowth of its structure and an engine of its evolution.” If that sounds like something you might hear in the early hours at a stone circle gathering, don’t worry. Jabr fleshes out his case with the latest science and journalistic flair in what is an impressive debut from the Oregon-based writer.
Becoming Earth is a reappraisal of the Gaia hypothesis, proposed in 1972 by British scientist James Lovelock and co-developed over several decades by US microbiologist Lynn Margulis. This idea of the Earth functioning as a self-regulating living organism has faced scepticism over the years, with many feeling it is untestable and strays into the realm of pseudoscience. In a 1988 essay, the biologist and science historian Stephen Jay Gould called Gaia “a metaphor, not a mechanism”.
Though undoubtedly a prodigious intellect, Lovelock was not your typical academic. He worked independently across fields including medical research, inventing the electron capture detector and consulting for petrochemical giant Shell. Add that to Gaia’s hippyish name – evoking the Greek goddess of Earth – and it’s easy to see why the theory faced a branding issue within mainstream science. Lovelock himself acknowledged errors in the theory’s original wording, which implied the biosphere acted with intention.
Though he makes due reference to the Gaia hypothesis, Jabr’s book is a standalone work, and in revisiting the concept in 2024, he has one significant advantage: we now have a tonne of scientific evidence for tight coupling between life and the environment. For instance, microbiologists increasingly speak of soil as a living organism because of the interconnections between micro-organisms and soil’s structure and function. Physicists meanwhile happily speak of “complex systems” where collective behaviour emerges from interactions of numerous components – climate being the obvious example.
To simplify this sprawling topic, Becoming Earth is structured into three parts: Rock, Water and Air. Accessible scientific discussions are interspersed with reportage, based on Jabr’s visits to various research sites. We kick off at the Sanford Underground Research Facility in South Dakota (also home to neutrino experiments) as Jabr descends 1500 m in search of iron-loving microbes. We learn that perhaps 90% of all microbes live deep underground and they transform Earth wherever they appear, carving vast caverns and regulating the global cycling of carbon and nutrients. Crucially, microbes also created the conditions for complex life by oxygenating the atmosphere.
In the Air section, Jabr scales the 1500 narrow steps of the Amazon Tall Tower Observatory to observe the forest making its own rain. Plants are constantly releasing water into the air through their leaves, and this drives more than half of the 20 billion tonnes of rain that fall on its canopy daily – more than the volume discharged by the Amazon river. “It’s not that Earth is a single living organism in exactly the same way as a bird or bacterium, or even a superorganism akin to an ant colony,” explains Jabr. “Rather that the planet is the largest known living system – the confluence of all other ecosystems – with structures, rhythms, and self-regulating processes that resemble those of its smaller constituent life forms. Life rhymes at every scale.”
When it comes to life’s capacity to alter its environment, not all creatures are born equal. Humans are having a supersized influence on these planetary rhythms despite appearing in recent geological history. Jabr suggests the Anthropocene – a proposed epoch defined by humanity’s influence on the planet – may have started between 50,000 and 10,000 years ago. At that time, our ancestors hunted mammoths and other megafauna into extinction, altering grassland habitats that had preserved a relatively cool climate.
Some of the most powerful passages in Becoming Earth concern our relationship with hydrocarbons. “Fossil fuel is essentially an ecosystem in an urn,” writes Jabr to illustrate why coal and oil store such vast amounts of energy. Elsewhere, on a beach in Hawaii an earth scientist and artist scoop up “plastiglomerates” – rocks formed from the eroded remains of plastic pollution fused with natural sediments. Humans have “forged a material that had never existed before”.
A criticism of the original Gaia hypothesis is that its association with a self-regulating planet may have fuelled a type of climate denialism. Science historian Leah Aronowsky argued that Gaia created the conditions for people to deny humans’ unique capacity to tip the system.
Jabr doesn’t see it that way and is deeply concerned that we are hastening the end of a stable period for life on Earth. But he also suggests we have the tools to mitigate the worst impacts, though this will likely require far more than just cutting emissions. He visits the Orca project in Iceland, the world’s first and largest plant for removing carbon from the atmosphere and storing it over long periods – in this case injecting it into basalt deep below the surface.
In an epilogue, we finally meet a 100-year-old James Lovelock at his Dorset home three years before his death in 2022. Still cheerful and articulate, Lovelock thrived on humour and tackling the big questions. As pointed out by Jabr, Lovelock was also prone to contradiction and the occasional alarmist statement. For instance, in his 2006 book The Revenge of Gaia he claimed that the only few breeding humans left by the end of the century would be confined to the Arctic. Fingers crossed he’s wrong on that one!
Perhaps Lovelock was prone to the same phenomenon we see in quantum physics where even the sharpest scientific minds can end up shrouding the research in hype and woo. Once you strip away the new-ageyness, we may find that the idea of Gaia was never as “out there” as the cultural noise that surrounded it. Thanks to Jabr’s earnest approach, the living Earth concept is alive and kicking in 2024.
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