The Quanta Podcast A Biography of Earth Across the Age of Animals
Oct 28, 2025
Peter Brannen, a science writer and Quanta contributor, dives into Earth's climate history and the pivotal role of CO2. He discusses the extremes of past climates and contrasts today's stability with perilous historical periods. Brannen explains how scientists reconstruct these climates through an impressive range of fossil data and models. He emphasizes the urgent need to understand anthropogenic climate changes, warning that our current cold climate is an anomaly. His insights reveal not just Earth's past, but also humanity's precarious future.
AI Snips
Chapters
Books
Transcript
Episode notes
CO2 As Earth's Primary Climate Knob
- Earth has hosted drastically different climates during the age of animals, often alien to humans.
- Changing atmospheric CO2 drove most of those climate shifts across deep time.
Fossils Confirm Extreme Ancient Warmth
- Past greenhouse climates were tens of degrees warmer than today, based on isotopic proxies and fossils.
- Fossils like Arctic alligators corroborate extreme warmth beyond model-only reconstructions.
Arctic Alligators Surprised Modelers
- A paleontologist found alligator fossils at Arctic latitudes during the Eocene and climate modelers doubted them.
- She joked modelers asked if they should 'put hair on these alligators' to reconcile the records.
