The Giants Shoulder #106 The Story Of How CO₂ Created ALL Life, Intelligence and Consciousness
Mar 26, 2026
Peter Brannen, award-winning science journalist and author, explains how CO2 shaped life, climate, intelligence, and extinctions. He traces CO2 from origin-of-life vents to planetary thermostats. He explores mass extinctions like the Permian, how life rewired Earth’s carbon cycle, and why today’s rapid CO2 rise is uniquely risky. Short, big-picture science on deep time and planetary change.
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Mike Russell Predicted The Right Vents
- Mike Russell predicted alkaline hydrothermal vents as origin sites for life before they were discovered.
- University of Washington later found vents matching his prediction, reinforcing geochemistry-first origin hypotheses.
Common Life Versus Rare Intelligence In The Cosmos
- Life's origin may be common in the universe but complex, intelligent life is far rarer due to many contingent planetary factors.
- Brannen cites requirements like a large moon and active plate tectonics that make Earth's path toward intelligence unlikely to repeat often.
Permian Extinction As A CO2-Driven Catastrophe
- The End-Permian extinction was driven by massive Siberian volcanism that released huge CO2 amounts, raising temperatures ~10°C and acidifying oceans.
- Rapid release overwhelmed geological sinks, causing ocean anoxia and long recovery times of ~10 million years.
