I propose that fire made our evolution possible. While there’s no scientific evidence for that hypothesis, we know that our life isn’t possible for long without it. If combustion suddenly stopped happening, how long would we last? That’s become our species survival test.
Consider an analogy to our situation. We hear a roar, but the river upon which we float is wide and smooth. It’s not like some malevolent entity is plotting to throw everyone on the raft over a cliff. We’re about to discover danger in the lay of this land.
We are now burning in one year the equivalent of one million years’-worth of plankton deposits as fossil fuel,... The Fabulous History of Phytoplankton and Why Our Species depends on it
It’s not as if some evil spirit designed animals so that a second source of energy, mastery of fire, was necessary for big brains and sentience to emerge.
That’s just the lay of this universe.
The odds have been stacked against us all along.
We co-evolved with fire. That second source of energy, beyond food, made Homo Sapiens a possibility. But plant fuel has limitations. Once a culture has denuded it’s continent for firewood, soil washes away, life gets too hard to support a developing civilization. Mastering fossil fuel solves that problem and makes globalization a possibility. But fossil fuel has catastrophic limitations.
Throwing carbon, which had been sequestered underground, back into the air a million times faster kickstarts positive feedbacks which can’t be turned off, changing albedo from melting snow and ice, burning forests in a drying climate, decreasing phytoplankton productivity and dissolving animal shells in hotter acidifying oceans (which slows sequestration), raising levels of water vapor (a greenhouse gas) in warmer air, and melting methane hydrate.
It’s not fair that processes which push planetary chemistry/temperature toward anoxic/hot conditions are both self-reinforcing and exponentially faster. Fairness is a social trait. Physical laws don’t answer to society.
It’s not fair that we need a second energy source, and none is an easy replacement for fire.
In short, planets which can support carbon-based advanced life forms which evolved using fire mastery are planets far from equilibrium. They can easily and rapidly transition into chemistry/temperature regimes hostile to that life.
We’ve been taking fire mastery for granted, failing to realize at the gut level both its significance to our evolution and the inherent danger that entails. Energy is not an externality for us, any more than food is.
Many have wondered why there’s no evidence of other advanced civilizations in the Milky Way. The Great Silence can now be seen as a warning. Given the planetary chemistry and physics we’re discovering here on Earth, our predecessors probably failed to grasp that very fleeting opportunity, at the height of their fossil fuel civilizations, to decarbonize. Once the feedbacks rev up, we sentients lose control. End of story.