The Living Earth, Part 2: “Earth’s Improbable Balance”
As Lovelock began his work, he asked a revolutionary question:
How has this planet remained hospitable to life for billions of years?
The data he gathered told him we shouldn’t be here, life shouldn’t be here, and yet—here we are. Not by luck, and not by accident.
“The climate and the chemical properties of the Earth now and throughout its history seem always to have been optimal for life. For this to have happened by chance is as unlikely as to survive unscathed a drive blindfolded through rush-hour traffic.”
The Temperature
Life began on this planet three billion years ago. Throughout those eons of ice ages and warming periods, of countless climate shifts—the surface temperature has remained within the range that supports life. Yet the sun has grown 25% hotter. By all logic, this entire planet should be an utterly lifeless desert right now. It isn’t.
The temperature has remained steady.
As Lovelock asked: “What parts of herself, I wonder, does she use as a thermostat?”
The Air
The air around us has been in a constant state of chemical imbalance since life began. It shouldn’t exist the way it does—its mixture of gases violate the rules of chemistry. Yet oxygen has remained at precisely the safe level for life for billions of years. A slight increase, and forests would ignite. A slight decrease, and we couldn’t breathe.
This critical element is so delicately sustained it seems almost impossible to believe.
The Ocean
For billions of years, salts have been washing into the sea from the land. By all calculation, the ocean should have become so salty that the cells of living organisms would dissolve. But it hasn’t.
It has remained in perfect balance—within the narrow margin where life can thrive.
Lovelock’s research showed one improbability after another, all maintained with precision. This led him to ask another question:
How does Gaia sustain the environment?
He began looking for global processes that would explain these improbable conditions, and specifically, ways the system’s own life forms might be doing the work.
The air is filled with carbon dioxide that helps hold heat close to the Earth’s surface, and until humans started burning fossil fuels, it was always relatively stable. How is this possible?
Temperature Control
The ocean absorbs carbon dioxide. Plankton at the ocean surface use it to grow protective shells, but they also need calcium—which the ocean doesn’t have, until the planet heats up.
Rising temperatures create more rainfall, which washes calcium from land to ocean. The flood of calcium causes plankton populations to explode, and trillions of new plankton absorb carbon into their shells. They grow and die rapidly, so it doesn’t take long for their heavy shells to sink to the ocean bottom, locking the carbon away.
Planktons’ basic biological need to grow a shell for protection removes carbon dioxide from the air and cools the entire planet back down.
What if plankton are Gaia’s version of a thermostat?
Ocean Balance
Coral reefs create quiet pools of heated water. When these evaporate, the salts they contain fall to the ocean floor.
Tiny animals called coral polyps gather in colonies to build these reefs. They do it to create a safe home for themselves, and as they build, they incidentally lower the local salt levels, which further ensures their safety.
What if the corals’ survival tactic plays a vital role in lowering salt levels for all ocean life?
“Is it possible that the Great Barrier Reef, off the north-east coast of Australia, is the partly finished project for an evaporation lagoon?”
Land Elements
And here’s where it gets beautiful. Lovelock noticed something about salmon. These fish swim upstream against impossible odds, returning to their birthwaters to spawn and die. Scientists used to see this simply as instinct. But we know now that when salmon die, they return phosphorus and nitrogen from ocean to land.
What if the salmon’s instinct is a part of Gaia’s bodily system—automatically maintaining the balance of essential elements it needs?
That would mean the salmon’s migration plays a vital role in keeping this planet habitable for all life forms.
“The strenuous and seemingly perverse efforts of salmon and eels to penetrate inland to places distant from the sea would then be seen to have their proper function.”
We exist within a living system that has regulated itself with the utmost precision for an unimaginably long period of time. Gaia constantly shifts and adjusts planetary conditions through the instinctive behaviors of her life forms.
They are her body, flawlessly orchestrating its own harmony.
But what if this planet is something more than a beautifully automated system? What if we take Gaia and apply conscious intent?
This is all we need to move from Lovelock’s science to Indigenous wisdom, from the body of the Earth to her soul. And it’s not that hard to imagine.
Continue the series: “Mother Earth”
Sources:
- James Lovelock, Gaia: A New Look at Life on Earth
- James Lovelock, We Belong to Gaia